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only_human 2016-05-15 21:19

Three little rockets, slightly used, sitting in a hanger, the first one says....
[URL="http://www.theverge.com/2016/5/15/11676080/spacex-falcon-9-at-cape-canaveral-photos-39a-hangar"]
SpaceX transports its landed Falcon 9 rocket to its temporary home in Florida[/URL]

[URL="http://www.fool.com/investing/general/2016/05/14/spacex-stuns-the-cynics.aspx"]SpaceX Stuns the Cynics[/URL]
[QUOTE]What comes next

The easy answer to this question is: Thaicom 8.

On May 26, SpaceX is scheduled to fly a Falcon 9 rocket out of its Space Launch Complex 40 installation at Cape Canaveral, carrying the Thai communications satellite into geosynchronous orbit (GSO) roughly 23,000 miles above Earth. After that, SpaceX has three launches scheduled to take place in June, two flying out of Cape Canaveral and one leaving from Vandenberg Air Force Base in California.

SpaceX may or may not choose to relaunch the same Falcon 9 that landed at sea on April 8 for one of these missions -- or for another mission yet to be announced. Elon Musk has said he's "aiming for relaunch around May or June," depending on whether SpaceX can find a customer willing to take a ride on a used rocket.

What comes after next

It's after SpaceX finds that guinea pig, though, that things really get interesting. According to the company's chief operating officer, Gwynne Shotwell, SpaceX plans to cut its usual advertised price for a space launch by about 30% when reusing a rocket. That should shave $20 million off the company's usual launch price of roughly $60 million.

At $40 million a rocket ride, it's going to be very difficult for any other space launch company to compete with SpaceX. Currently, Boeing and Lockheed Martin's space launches cost $125 million and up. Arianespace has a plan in place to launch satellites two at a time aboard its new Ariane 64 rocket (once it's built), for an average launch cost of $63 million -- but even this won't compete with a $40 million price, if SpaceX is able to offer that consistently.

The key, though, is consistency. SpaceX has launched and landed three rockets -- and deserves all possible kudos for that. But can it re-launch and re-land a rocket? Can it rere-launch it and rere-land it? Because if it can, SpaceX will be able to underprice all comers, and change the economics of space exploration forever.

And in as little as a month and a half -- or less! -- we'll know the answer.[/QUOTE]

only_human 2016-05-21 03:35

Politics and Space.
 
Orbital ATK uses decommissioned ICBM motors for government satellite launches.
What they want to do is get permission to use them for commercial payloads also.
[URL="http://www.spaceflightinsider.com/organizations/orbital-sciences-corp/missiles-minotaurs-orbital-atk-converting-minuteman-icbms-launch-vehicles/"]MISSILES TO MINOTAURS: ORBITAL ATK SEEKING TO USE FORMER ICBM PARTS[/URL]
[QUOTE]In an interesting turn of events, commercial aerospace companies, who once fought to open the launch service provider market to others, appear to be now opposing this latest effort to commercialize space assets.

According to a report appearing on BloombergView, Congress has banned the use of decommissioned ICBM components on national security grounds.

Similar national security concerns have been raised about the RD-180 rocket engine. Ever since the United States’s former Cold War rival carried out military actions in Ukraine in 2014, loud calls have been made to cease the import of these engines.

In the case of these excess Peacekeeper and Minuteman motors, it would seem that Congress would have a plausible way to not only alleviate some of those concerns, but also, as BloomBergView put it, give taxpayers some return on the billions of dollars the Pentagon has already spent in storing them and save the cost of destroying them.

“Currently, the Air Force maintains around a thousand excess ICBMs, which are stored in bunkers at two military bases in the United States,” Pieczynski said. “We and other companies would like to purchase those at a fair market price and bolster the U.S. market.”[/QUOTE]

ULA is a joint venture of Lockheed Martin Space Systems and Boeing Defense, Space & Security, and they currently use Russian RD-180 rocket motors which are a fierce bone of contention in Congress. [URL="http://phys.org/news/2016-05-aerospace-giants-aim-emerging-upstarts.html"]Aerospace giants are taking aim at emerging upstarts[/URL].
[QUOTE]ULA could continue to compete with SpaceX if it is allowed to increase its purchase of Russian rockets, from nine to as many as 18, as proposed in the defense-bill amendment approved by the House committee late last month. The amendment was sponsored by Rep. Mike Coffman, R-Colo., whose congressional district includes ULA's headquarters.
During the bill markup, Coffman said a "hasty" prohibition on Russian rocket engines would harm national security and launch competition and raise concerns about fiscal responsibility.

"The Air Force has asked for 18 Russian-made engines to ensure a safe, practical and responsible transition away from RD-180 powered Atlas V rocket, and that is exactly what my amendment does," he said. "Ending our reliance on Russian engines is clearly in the national security interest of the United States, but not at the expense of the paramount requirement of assured access for national security missions."[/QUOTE]
Yesterday the house passed a bill increasing the allowed purchase from 9 motors to 18. [URL="http://www.spacepolicyonline.com/news/house-passes-fy2017-ndaa"]House Passes FY2017 NDAA - UPDATE[/URL]
[QUOTE]The House passed the bill by a vote of 277-147, with most Democrats voting against it (142 against, 40 in favor). If the President were to veto the bill, there would be enough votes to sustain it. A two-thirds vote of both chambers is required to overturn a veto. When the House has its full complement of 435 members, that means 290 votes are needed to overturn, 13 more than voted in favor of the bill. The bill has a long way to go, however. In addition to the RD-180 issue, there are many differences with the SASC version, which is expected to be debated by the Senate next week.[/QUOTE]

It will be interesting to see if SpaceX will be able to get enough launches to make rocket core relaunches an economically viable path forward.

Here is a combined list of upcoming launches: [URL="https://spaceflightnow.com/launch-schedule/"]Launch Schedule[/URL]

It looks like lawyers will have a role in private enterprise's Mars ambitions also. [URL="http://www.universetoday.com/129024/spacex-calls-lawyers-2018-mars-shot/"]SPACEX CALLS IN THE LAWYERS FOR 2018 MARS SHOT[/URL]

only_human 2016-05-26 01:01

Tomorrow morning (Thursday) Bigelow inflation. With Nasa TV follow-up
Tomorrow evening another SpaceX Geosynchronous Transfer Orbit satellite launch.

chalsall 2016-05-26 22:44

[QUOTE=only_human;434847]Tomorrow morning (Thursday) Bigelow inflation. With Nasa TV follow-up
Tomorrow evening another SpaceX Geosynchronous Transfer Orbit satellite launch.[/QUOTE]

Not a lucky day for space geeks... The BEAM didn't inflate properly, and tonight's launch of Falcon 9 has been delayed until tomorrow....

only_human 2016-05-27 01:40

[URL="http://www.bloomberg.com/news/articles/2016-05-26/elon-musk-s-most-unexpected-success-is-the-spacex-live-stream"]Elon Musk's Most Unexpected Success Is the SpaceX Live-Stream[/URL]
[QUOTE]The palpable excitement emanating from within SpaceX is part of what makes the webcasts so engaging for so many people. In April, when Falcon 9 nailed its first droneship landing, the webcast hosts could barely contain their enthusiasm. Kate Tice, a process improvement engineer wearing an "Occupy Mars" T-shirt, was so elated that she told roughly 80,000 viewers "My face hurts so much right now, I can't believe it." The 36-minute webcast that included the first droneship landing has been viewed 1.53 million times on YouTube. A separate clip featuring a 360-degree view of that same landing has garnered more than 1.9 million views.[/QUOTE]
[url]https://m.youtube.com/watch?v=zBYC4f79iXc[/url]
[YOUTUBE]zBYC4f79iXc[/YOUTUBE]

chalsall 2016-05-27 21:51

They're making this appear easy....

only_human 2016-05-27 22:29

Hard landing; some risk of tipping.
[url]https://www.reddit.com/r/spacex/comments/4ld4oz/elon_musk_on_twitter_rocket_landing_speed_was/[/url]

[QUOTE]Elon Musk on Twitter: "Rocket landing speed was close to design max & used up contingency crush core, hence back & forth motion. Prob ok, but some risk of tipping."[/QUOTE]

only_human 2016-05-28 02:31

First stage landing time-lapse video from first stage camera.
[url]https://www.instagram.com/p/BF7sxM9QES7/?hl=en[/url]

I think I've seen this scene before when Luke damages Darth Varder's spacecraft but he tumbled away to safety.

Or maybe this was the part just before Luke ran around a swamp with a Muppet on his back.

firejuggler 2016-05-28 13:37

shock dampener explained
[youtube]LDpGCfZAraU[/youtube]


those were also used in the moon landing
[url]http://heroicrelics.org/info/lm/landing-gear-strut-honeycomb.html[/url]

only_human 2016-05-28 18:39

BEAM

I can't decide if it looks more like a wart or a mushroom.
[url]http://www.ustream.tv/nasahdtv[/url]
Update: one minute and nines seconds total inflation added so far. The last and longest increment was eight seconds. I have now decided that it looks and sounds like one of those stovetop Jiffy Pop popcorn snacks except for being cloth instead of shiny aluminum.

Does it come with wallpaper and can tenants use their own choice of paint? Hope no one eats everyone else's takeout food in the fridge.

xxxxxxxxx

A slower first stage landing video with a graphical overlay to show the position of the drone ship during the rocket descent.
[URL="https://www.reddit.com/r/spacex/comments/4lfr64/video_analysis_of_the_spacex_thaicom8_landing/"]VIDEO: Analysis of the SpaceX Thaicom-8 landing video shows new, interesting details about how SpaceX lands first stages[/URL] (reddit thread) Thread comments suggest that this stage doesn't look as overcooked as the last shrimp on the barbie.
[YOUTUBE]b-yWTH7SJDA[/YOUTUBE]

only_human 2016-05-29 16:01

h/t [URL="https://plus.google.com/+JohnHigginbotham70/posts/AyhBZz91EcC"]John Higginbotham[/URL]: Flat Earther debunks Space X landing

This latest beautiful landing video clip has now also received Flat Earther scrutiny. They really don't like seeing a curved horizon.
[url]https://youtu.be/WLE-ocDoXrs[/url]
[YOUTUBE]WLE-ocDoXrs[/YOUTUBE]

chalsall 2016-05-29 16:18

[QUOTE=only_human;435076]This latest beautiful landing video clip has now also received Flat Earther scrutiny. They really don't like seeing a curved horizon.[/QUOTE]

LOL... Actually, this is one of the reasons I'm currently modelling Trump with a 20% possibility of becoming PoTUS.

kladner 2016-06-01 02:41

[QUOTE=chalsall;435080]LOL... Actually, this is one of the reasons I'm currently modelling Trump with a 20% possibility of becoming PoTUS.[/QUOTE]
I devoutly hope that you are correct, even if the alternative is HRC.
Danger! Will Robinson! :max:

only_human 2016-06-01 22:54

[URL="https://www.reddit.com/r/spacex/comments/4lz2y6/thaicom8_recovery_thread/"]Thaicom-8 Recovery Thread[/URL]
Stage one is four hours away from port but not traveling any more until tomorrow, it seems.
[QUOTE]Current status: (as of Wed June 1 at 4:30 PM EDT)
Update 5 PM EDT: Good photo of leaning stage
Update 3:30 PM EDT: UK submarine enters port, possibly explaining the NOTAM. (transfer of missiles)
OCISLY is floating approximately 35 km (22 miles) from Port Canaveral with its support vessels. It is unknown when they will continue into port. Their average speed of movement back from the landing area had been 8.8 km/h (5.5 mi/h), suggesting an approx 4 hour journey once they get back underway.[/QUOTE]
Once this recycling stuff really starts happening we'll be into crack inspection and clearing out coke.

[URL="http://spacenews.com/french-space-minister-calls-for-european-rocket-rd-effort-says-spacex-victory-still-tbd/"]French space minister calls for European rocket R&D effort, says SpaceX victory still TBD[/URL]

[URL="https://www.reddit.com/r/spacex/comments/4m0gfg/russian_space_minister_rogozin_program_will_never/"]Russian Space Minister Rogozin: Program Will “Never Catch Up” to SpaceX Innovation[/URL]
I don't know enough to judge this kind of thing but think this problem is endemic most places here and there.

As for the fairly new RD-181s, two pairs were bought last year and I think there is some contract for upwards of 50 or 60.

That is what Orbital ATK switched to after a previous rocket explosion. It has more power and they may be able to meet a cargo commitment with four launches instead of five if NASA's cargo can be apportioned thusly. They just did a hot fire test firing yesterday. They've had some rough times; they bought a couple of rides for their Centaur on ULA's Atlas 5 to meet contract commitments after the explosion -- and one Atlas 5 launch had its own fuel anomaly leaving the versatile upper stage Centaur with a rough situation and barely enough fuel to complete the mission.

----

[URL="http://www.space.com/33020-pluto-best-images-new-horizons-video.html"]Amazing Pluto Shines in Best Close-Up Views Yet (Photo, Video)[/URL]
[QUOTE]You need to zoom in on the newly released Pluto mosaic to fully appreciate the rich level of detail it provides. You can do that by checking out the full-resolution image here: [url]http://www.nasa.gov/sites/default/files/thumbnails/image/nh-fullresolutionnoodle.jpg[/url]

New Horizons captured the images from a distance of about 9,850 miles (15,850 kilometers) on July 14, 23 minutes before the probe's closest approach to Pluto (which brought it to within 7,800 miles, or 12,550 km, of the dwarf planet's surface).

Though the encounter took place more than 10 months ago, New Horizons is still beaming flyby data home, and likely won't be done doing so until this coming fall, mission team members have said.

New Horizons may have another flyby in its future. Stern and his colleagues have submitted a proposal to send the spacecraft — which launched in January 2006 — zooming past a small object about 1 billion miles (1.6 billion km) beyond Pluto, called 2014 MU69. If NASA approves and funds this mission extension, the encounter with 2014 MU69 would take place Jan. 1, 2019.
[/QUOTE]
[URL="http://nasawatch.com/archives/2016/06/and-todays-too.html"]And Today's 'Too Lazy To Call NASA And Ask' Award Goes To ...[/URL]
[QUOTE]
[QUOTE]Why did they wait until NOW to release these? pics taken in 2015 and we pay their salaries in tax dollars [url]https://t.co/hhXxrfsWEr[/url]
— Greta Van Susteren (@greta) June 1, 2016[/QUOTE]

NASA releases sharpest images of Pluto ever taken; captured via spacecraft's flyby in 2015. [url]https://t.co/pcooJYhuhY[/url] [url]pic.twitter.com/tGljue37U9[/url]
— NBC Nightly News (@NBCNightlyNews) June 1, 2016

Why It'll Take New Horizons 16 Months to Send Us This Week's Data, Gizmodo (2015)
[QUOTE]"4,000 bits per second may be double our current downlink speed, but downloading planetary science data over 3 billion miles is still quite a bit slower than loading your email on a 56K connection. Hence the reason it's going to take us an estimated 16 months to send home all the data we collect in the next several days."[/QUOTE][/QUOTE]

chalsall 2016-06-02 17:03

So, I was interested in finding out if SpaceX successfully brought back the first stage for thaicom8 (edit: to port).

Unfortunately, I had to rely on a Periscope feed from a woman (Alicia Murphy) and her son who were demonstrably dumber than bricks. All other web camera feeds demanded payment.

The good news is the first stage returned to port successfully. The bad news is I had to listen to their stupid commentary (although on extremely low volume).

I had never viewed Periscope before. I will never again.

only_human 2016-06-02 17:39

[URL="https://m.youtube.com/watch?v=balG1nQ_bEE"]SpaceX Rocket coming into Port Canaveral 6/2/16 Full Video[/URL] 52:41 YouTube via SurfGuru
[YOUTUBE]balG1nQ_bEE[/YOUTUBE]

1st viewer!
52:41 video. About ten minutes in a few vessels decrease the monotony. 43 minutes in - near some docks. 45 minutes - traveling through some channel. doesn't seem to capture final berthing

Actually these 4 minutes are the better parts:
SpaceX Rocket Returns to Port Surfguru.com cam feed 6/2/16 via SurfGuru
[url]https://m.youtube.com/watch?v=Wb8tqvMGGhI[/url]
[YouTube]Wb8tqvMGGhI[/YouTube]

spacex: Rocket back at port after careful ocean transit (Instagram)
[url]https://www.instagram.com/p/BGKRcY3F8XC/[/url]

Uncwilly 2016-06-02 22:42

[QUOTE=chalsall;435384]All other web camera feeds demanded payment.[/QUOTE]Start up a private browser session, turn off ad-block, and use[URL="http://www.portcanaveralwebcam.com/"]Port Canaveral Web cam.[/URL] They have been delivering hi-res video during the move in and transfer to shore. A lot of the reddit folks have been clicking ads as thanks for the great quality that they have been delivering.

only_human 2016-06-06 23:43

[URL="https://www.nasaspaceflight.com/2016/06/williams-beam-expandable-module-milestone/"]Williams enters BEAM for expandable module milestone[/URL]
[QUOTE]NASA astronaut Jeff Williams has [B]ingressed[/B] the Bigelow Expandable Activity Module (BEAM) on Monday, the first time an American has entered an inflatable module in space. The milestone came after teams on the ground helped with a scavenger hunt on the Station to replace a missing part that was required for Monday’s historic event.[/QUOTE]
I do not know what the missing part was nor do I know Williams' [URL="https://en.m.wikipedia.org/wiki/Ingress_(video_game)"]Ingress[/URL] portal faction.

I read somewhere that they had to move power lines to accommodate the latest recovered Falcon booster's trip to the hanger. That may get old fast. [URL="http://www.universetoday.com/129310/recovered-spacex-falcon-9-lifts-off-2nd-time-after-baby-made-it-home-gallery/"]RECOVERED SPACEX FALCON 9 ‘LIFTS OFF’ 2ND TIME AFTER ‘BABY MADE IT HOME!” – GALLERY[/URL]
[URL="http://www.latimes.com/business/la-fi-moon-express-20160606-snap-story.html"]
U.S. government close to approving private moon mission, reports say[/URL]
[QUOTE]The MX-1 lander, which Moon Express said is capable of carrying scientific and commercial payloads, is set to blast off in 2017 on Los Angeles-based Rocket Lab’s Electron rocket. The rocket is awaiting its first flight.

In a video posted on its website, Moon Express said it would start by launching robotic landers with payloads to the surface of the moon and progress to exploring for resources, learning how to process the materials, and transporting them back to Earth.

Moon Express has said it is looking for platinum group metals, rare earth elements and Helium-3, which some believe could be a safer nuclear fuel and is present in larger quantities on the moon, according to the European Space Agency.[/QUOTE]

only_human 2016-06-07 01:13

[QUOTE]SpaceX ‏@SpaceX
Fantastic four
[url]https://twitter.com/SpaceX/status/739984652136374273[/url]

Room for one more then somebody has to get kicked out of the nest.[/QUOTE]
Four boosters sitting in a hanger.

Uncwilly 2016-06-07 01:36

[QUOTE=only_human;435663]Four boosters sitting in a hanger.[/QUOTE]One is heading to hang from the rafters in Space-X's headquarters. I bet the Smithsonian has sent Space-X a letter stating that they would accept a returned Falcon 9. That is their way of asking for one (according to the story that I heard Dick Rutan tell.)

only_human 2016-06-07 02:44

[QUOTE=Uncwilly;435666]One is heading to hang from the rafters in Space-X's headquarters. I bet the Smithsonian has sent Space-X a letter stating that they would accept a returned Falcon 9. That is their way of asking for one (according to the story that I heard Dick Rutan tell.)[/QUOTE]
In this case, I think the Smithsonian may find Elon Musk to be particularly receptive to a gentle request.

[URL="http://www.smithsonianmag.com/innovation/2015-smithsonian-american-ingenuity-awards-180956989/"]Smithsonian's 2012 American Ingenuity Award Winners[/URL]
[QUOTE]The Smithsonian has been celebrating innovation in American culture for more than 150 years and the highest honor we now give in that regard is the American Ingenuity Award, which showcases revolutionary breakthroughs in the arts and sciences, education and social progress. Winners and presenters have included Nobel laureates, rock stars and civil rights icons—from physicist Stephen Hawking, to Tesla and [B]SpaceX founder Elon Musk[/B], to musicians David Byrne and St. Vincent, writer and educator Dave Eggers, virtual reality inventor Palmer Luckey, and Grammy-award winner Rosanne Cash. The American Ingenuity Award itself was created by the artist Jeff Koons.[/QUOTE]

only_human 2016-06-11 04:50

Tales from the void of space
 
[URL="https://www.wired.com/2016/06/time-astronaut-lost-wedding-ring-space/"]THAT TIME AN ASTRONAUT LOST HIS WEDDING RING IN SPACE[/URL]
[QUOTE]On the second day of the 1972 11-day trip to the moon and back, command module pilot Ken Mattingly lost his wedding ring. “It just floated off somewhere, and none of us could find it,” Duke says. Mattingly, perhaps worried his wife would accuse him of some extraterrestrial impropriety, spent his free moments desperately searching for the ring.[/QUOTE]
[QUOTE]On the ninth day, the team went out for a space walk. The hatch was open, and Mattingly was floating alongside the ship, tending to a biological experiment anchored on a 10-foot pole. Duke suited up and floated out to check on him.

“It was spectacular out there,” he says. “The moon was over my left shoulder about 50,000 miles away and it was huge. To the lower right was the earth, just a thin sliver of blue and white, and I was mesmerized.”

As he turned to head back in, something caught his eye, small, glistening in the sun, floating slowly out of the door. He reached his big gloved hand out to catch the ring and missed. “Well,” he thought, “lost in space.”

Duke, Mattingly, the ship, and the ring were flying through space together at 3,000 feet per second, but in the absence of wind resistance, as Duke puts it, things just “move along together.” So there they were, floating while really zooming along—Charlie watching the unrushed ring head to its fate in the vast darkness.

But as he watched, Duke realized the ring was headed right for the back of Mattingly’s head. The astronaut, unaware, was absorbed in his experiment when the ring hit him right on the back of the helmet, turned 180 degrees, and headed back for the hatch. About three minutes later, Charlie caught it in his big gloved hand.[/QUOTE]

only_human 2016-06-11 20:20

[QUOTE]Published on Jun 11, 2016 United Launch Alliance launched NROL-37 atop a Delta IV rocket from Cape Canaveral AFB, FL. launch complex LC-37 [STRIKE]June 16[/STRIKE] at 1:51 pm EDT. The Delta IV was in the heavy configuration with 3 booster cores. The secretive payload is being launched for the National Reconnaissance Office in support of national defense. The last time a Delta IV heavy launched was for NASA's test of the Orion Capsule. Congratulations to ULA and the crew from Cape Canaveral AFB for a flawless launch.

Thanks to United Launch Alliance for a live stream of the launch and thank you for watching. This video was edited for time.[/QUOTE]
[url]http://youtu.be/wQq-erIzAX0[/url]
[YOUTUBE]wQq-erIzAX0[/YOUTUBE]
Launch occurs just before seven minutes into this video. Coverage continues up to fairing separation wherupon "at our customer's request we will now conclude our live coverage."

The Delta IV heavy is the world's most powerful launch configuration at this time. If I remember the factoids from this video correctly, it is the sixth such launch for the NRO and the 32nd Delta IV launch since operations began in 2002.

Mark Rose 2016-06-11 23:01

You can tell ULA is old-school, using non-metric units. Still cool seeing a triple-core launch though!

only_human 2016-06-12 00:01

[QUOTE=Mark Rose;436052]You can tell ULA is old-school, using non-metric units. Still cool seeing a triple-core launch though![/QUOTE]
Speaking of old school, there is nimbleness afoot in unexpected places:
[URL="http://www.wired.com/2016/06/unknown-lab-millennials-fast-tracking-nasas-missions/"]The Unknown Lab of Millennials Fast-Tracking NASA’s Missions[/URL]
A Rapid Response Radiation Survey to help predict high flying airline workers radiation exposure:
[QUOTE]Just three days after the picnic-table meeting, 32-year-old Miller presented the mission concept to NASA’s bigwigs with the money, who funded R3S just a week after that. Within 28 days—the length of a lunar cycle, or a global zombie virus outbreak—they had closed a deal with the Defense Advanced Research Projects Agency to launch it aboard a small satellite. R3S will launch later this year, after its engineers spent just four months working on its design.[/QUOTE]

Oh, and June 15 is SpaceX's next launch date:
[QUOTE]SpaceX ‏@SpaceX
Next launch targeting June 15 for launch of the @Eutelsat_SA 117 West B and ABS-2A satellites. Launch window opens 10:29 am ET, 2:29 pm UTC
[url]https://twitter.com/SpaceX/status/741741731608072192[/url]


[url]http://www.eutelsat.com/en/satellites/future-satellites/EUTELSAT-117WB.html[/url]

[url]http://www.absatellite.com/satellite-fleet/?sat=abs2a[/url][/QUOTE]

Mark Rose 2016-06-12 01:54

[QUOTE=only_human;436056]Speaking of old school, there is nimbleness afoot in unexpected places:
[URL="http://www.wired.com/2016/06/unknown-lab-millennials-fast-tracking-nasas-missions/"]The Unknown Lab of Millennials Fast-Tracking NASA’s Missions[/URL]
A Rapid Response Radiation Survey to help predict high flying airline workers radiation exposure:[/QUOTE]

That's awesome! It's about time they did a program like that.

I still need to get myself a gamma ray spectrometer. I've flown with a Geiger counter several times and it's fun seeing readings 30 times background.

Mark Rose 2016-06-12 05:04

[url]http://i.imgur.com/CvEstao.jpg[/url]

only_human 2016-06-15 04:47

Just a reminder:
[URL="https://www.nasaspaceflight.com/2016/06/spacex-falcon-9-dual-satellite-launch/"]SpaceX set for Falcon 9 dual satellite launch[/URL]
[QUOTE]SpaceX will launch its sixth mission of the year Wednesday, with a Falcon 9 rocket carrying a pair of communications satellites – Eutelsat 117 West B and ABS-2A – into orbit. Liftoff from SLC-40 at Cape Canaveral is expected during a 44-minute window that opens at 10:29 local time (14:29 UTC).

SpaceX Launch:

Wednesday’s launch is the twenty-sixth launch of SpaceX’s Falcon 9 vehicle; coming less than three weeks after the previous mission, which deployed the Thaicom 8 satellite in late May.

As with the Thaicom launch, Falcon will again be targeting a geosynchronous transfer orbit; this time carrying a pair of smaller satellites instead of one larger one.[/QUOTE]

Oh, and in funny headline mistakes I've been looking at this so-far-uncorrected headline all day:
[QUOTE]
[URL="http://nhv.us/content/57057-united-launch-alliances-delta-iv-heavy-lifts-california-s-cape"]United Launch Alliance's Delta IV Heavy lifts off from [B]California[/B]'s Cape Canaveral[/URL]
NH Voice - ‎16 hours ago‎
United Launch Alliance's Delta IV Heavy, the most powerful rocket in the world, has lifted off from Cape Canaveral in [B]California[/B] on June 11, with a mission to launch a US spy satellite into orbit.[/QUOTE]
Later in the article they quote someone else who had it right:
[QUOTE]According to a report in Tech Times by Rhodi Lee, "The United Launch Alliance Delta IV Heavy, touted as the world's most powerful rocket, blasted off from Cape Canaveral Air Force Station in Florida Saturday, June 11, afternoon carrying a United States spy satellite. The launch was supposed to take place on Thursday, June 9, but it was delayed for several days because of rainy weather conditions."[/QUOTE]
update:
I just noticed a project that is planned to be launched on a Falcon Heavy in 2017
[URL="http://earthsky.org/space/measuring-time-in-deep-space"]Measuring time in deep space[/URL]
[QUOTE]Sending an atomic clock to deep space

The ground clocks used for these measurements are the size of a refrigerator and operate in carefully controlled environments – definitely not suitable for spaceflight. In comparison, DSAC, even in its current prototype form as seen above, is about the size of a four-slice toaster. By design, it’s able to operate well in the dynamic environment aboard a deep-space exploring craft.

One key to reducing DSAC’s overall size was miniaturizing the mercury ion trap. Shown in the figure above, it’s about 15 cm (6 inches) in length. The trap confines the plasma of mercury ions using electric fields. Then, by applying magnetic fields and external shielding, we provide a stable environment where the ions are minimally affected by temperature or magnetic variations. This stable environment enables measuring the ions’ transition between energy states very accurately.[/QUOTE]
I don't know why it's going on Falcon Heavy to low earth orbit but that is the plan:
[QUOTE]Countdown to DSAC launch

The DSAC mission is a hosted payload on the Surrey Satellite Technology Orbital Test Bed spacecraft. Together with the DSAC Demonstration Unit, an ultra stable quartz oscillator and a GPS receiver with antenna will enter low altitude Earth orbit once launched via a SpaceX Falcon Heavy rocket in early 2017.

While it’s on orbit, DSAC’s space-based performance will be measured in a yearlong demonstration, during which Global Positioning System tracking data will be used to determine precise estimates of OTB’s orbit and DSAC’s stability. We’ll also be running a carefully designed experiment to confirm DSAC-based orbit estimates are as accurate or better than those determined from traditional two-way data. This is how we’ll validate DSAC’s utility for deep space one-way radio navigation.[/QUOTE]
Here are the five projects on that Orbital Test Bed
[url]https://www.sstl.co.uk/Missions/Orbital-Test-Bed--OTB-/News/OTB--The-Mission[/url]

kladner 2016-06-15 05:42

[QUOTE]I don't know why it's going on Falcon Heavy to low earth orbit but that is the plan:[/QUOTE]
Perhaps SpaceX wants to test the rocket in a non-demanding launch? Just guessing.

only_human 2016-06-15 06:24

[QUOTE=kladner;436258]Perhaps SpaceX wants to test the rocket in a non-demanding launch? Just guessing.[/QUOTE]
I just skimmed a white paper on Surrey Satellite Technology's hosted mission concept. It's a way getting a cheaper ride to orbit as a secondary payload.

Actually the larger mission is full of stuff:
[url]https://en.wikipedia.org/wiki/Space_Test_Program#Upcoming_activities[/url]
[QUOTE]The STP-2 (DoD Space Test Program) payload is scheduled to be launched aboard a Falcon Heavy in March 2017.[8] The payload should include an ISAT (Innovative Spacebased radar Antenna Technology) flight demonstrator satellite massing over 5000 kg, and COSMIC-2, a cluster of six satellites, massing at 277.8 kg each.[9] The ISAT program aims to deploy extremely large (up to 300 yards) electronically scanning radar antennas in orbit.[10] The primary role of the COSMIC-2 satellite constellation is to provide radio occultation data with an average latency of 45 minutes. The six satellites will be placed on an orbit with an inclination of 24 to 28.5 degrees with six separate orbital planes with 60 degree separation between them.[11] The integrated payload stack will be integrated using EELV Secondary Payload Adapter. Two ESPA Grande rings will be used to mount the six COSMIC-2 satellites beneath the ESPA ring hosting the DSX payload and avionics modules.[12] STP-2 will also host up to 8 CubeSat nanosatellites deployed with P-PODs (Poly Picosatellite Orbital Deployers).[9]

Other secondary payloads include LightSail,[13] Prox-1 nanosatellite,[13] Oculus-ASR nanosatellite,[14] GPIM,[15][16][17] and the Deep Space Atomic Clock.[18][/QUOTE]
One project, GPIM, is NASA's greener satellite propellant that we briefly talked about here sometime back.

only_human 2016-06-15 22:57

Okay, today's SpaceX interlude:
[URL="http://spaceflight101.com/falcon-9-launches-satellites-for-eutelsat-and-abs/"]Pair of Communication Satellites orbited by Falcon 9, First Stage Landing ends in Blaze of Fire[/URL]
About the two satellites sharing a launch, Boeing has a patent on this stacked configuration. This article has a launch and landing recap including a picture of the returning booster briefly on deck before kablooey.
[QUOTE]Wednesday’s mission marked SpaceX’s second dual-payload flight to GTO as the company is less inclined to support multi-customer flights due to schedule risks arising in case of delays with one of the passengers. However, with both satellites from a single manufacturer and delivered as a single-piece stack by Boeing, SpaceX was more or less able to treat the mission as a standard single-payload launch.

Dual-launch capability is an inherent feature of Boeing’s BSS-702SP satellite bus that reduces spacecraft mass to enable customers to share the cost of a single launch vehicle. Boeing developed its own adapter system that joins the two satellites and provides satellite separation when arriving in orbit. The physical adapter remains attached to one of the two nearly identical satellites that have a combined mass of around 4,100 Kilograms.

The BSS-702SP satellites rely on electric propulsion, featuring XIPS-25 ion thrusters for their transition from GEO Transfer Orbit to their high-altitude perch in Geostationary Orbit. Ion thrusters are more efficient but lack the thrust of chemical propulsion system, creating a longer transfer time into GEO, planned to be on the order of half a year for the two satellites.[/QUOTE]

Here's another picture of the booster on the drone ship deck from a reddit thread reference: [url]http://m.imgur.com/YHBjbco?r[/url]

It is obscurred by smoke with difficult to discern details that are reminiscent of the Alien vs Preditor Requiem movie which had such bad lighting that it could have been refilmed starring a screaming trash bag in a dark alley and I wouldn't notice much difference.
Here is a Google search on: [URL="https://www.google.com/search?q=alien+movies&q=alien+vs+predator+requiem+lighting"]alien movies alien vs predator requiem lighting
[/URL]

Elon Musk promised more video. Here are some tweets:
[QUOTE]Elon Musk ‏@elonmusk
Landing video will be posted when we gain access to cameras on the droneship later today. Maybe hardest impact to date. Droneship still ok.

Elon Musk ‏@elonmusk
Upgrades underway to enable rocket to compensate for a thrust shortfall on one of the three landing engines. Probably get there end of year.

Elon Musk ‏@elonmusk
Looks like thrust was low on 1 of 3 landing engines. High g landings v sensitive to all engines operating at max.[/QUOTE]

only_human 2016-06-17 02:16

More Twitter posts with a landing video from some distance.
[QUOTE]
[QUOTE]Elon Musk ‏@elonmusk
As mentioned at the beginning of the year, I'm expecting ~70% success rate on landings for the year. 2016 is the year of experimentation.[/QUOTE]
[QUOTE]Elon Musk ‏@elonmusk
Looks like early liquid oxygen depletion caused engine shutdown just above the deck
0:20[/QUOTE]
(video): [url]https://mobile.twitter.com/elonmusk/status/743602894226653184/video/1[/url]
[QUOTE]Elon Musk ‏@elonmusk
Turns out the landing was not as fast we thought, but still hard enough to destroy the primary airframe and accordion the engines[/QUOTE][/QUOTE]

Dubslow 2016-06-17 10:20

One of several motion-stabilized versions of the tweeted video: [url]https://www.youtube.com/watch?v=5ilfd6H1Kp0[/url]

only_human 2016-06-17 22:15

[URL="http://www.theverge.com/2016/6/17/11962662/nasa-iss-three-astronauts-return-flight-watch-live-stream"]Watch three astronauts leave the International Space Station tonight[/URL]
Tim Peake:
[QUOTE]He’s also clearly had fun up there, [URL="https://www.youtube.com/watch?v=2Lz5UeROyXM"]making this cute video about how to get dizzy in space. (Spoiler: you can’t.)[/URL][/QUOTE]
[YOUTUBE]2Lz5UeROyXM[/YOUTUBE]

Mark Rose 2016-06-19 14:03

Flight 4 of New Shepard happening right now:

[youtube]EI-tGVFg7PU[/youtube]

xilman 2016-07-02 18:47

Juno, 4th July
 
[URL="http://www.bbc.co.uk/news/science-environment-36695270"]Burn, baby, burn[/URL]

jasong 2016-07-04 20:38

[QUOTE=xilman;437444][URL="http://www.bbc.co.uk/news/science-environment-36695270"]Burn, baby, burn[/URL][/QUOTE]
I know the spot on Jupiter is called the Red Spot(not sure if I should capitalize that), but has the color changed or has it always been an orange spot?

(Googled it, and it's literally[old people literally ;) ] changed color)

Btw, I ask googlable questions because I'm an old dude. It's something I'm continuously having to work on. Don't forget that Google has only been around for about a decade or so.

xilman 2016-07-04 20:42

[QUOTE=jasong;437590]I know the spot on Jupiter is called the Red Spot(not sure if I should capitalize that), but has the color changed or has it always been an orange spot?[/QUOTE]:google:

xilman 2016-07-05 05:42

[URL="http://www.bbc.co.uk/news/science-environment-36710768"]In orbit[/URL]

Xyzzy 2016-07-14 13:43

[url]http://arstechnica.com/science/2016/07/a-cold-war-mystery-why-did-jimmy-carter-save-the-space-shuttle/[/url]

Spherical Cow 2016-07-14 22:59

[QUOTE=Xyzzy;438099][url]http://arstechnica.com/science/2016/07/a-cold-war-mystery-why-did-jimmy-carter-save-the-space-shuttle/[/url][/QUOTE]

Good one- thanks for posting that.

Norm

xilman 2016-07-16 10:54

[URL="http://www.space.com/33412-nasa-aerobot-drone-saturn-moon-titan.html"]Flying on Titan[/URL]

only_human 2016-07-17 02:09

Busy times at the ISS
h/t Friends of Nasa
[QUOTE]Russian Cargo Ship Launches to International Space Station
July 16, 2016: At the Baikonur Cosmodrome in Kazakhstan, the unpiloted ISS Progress 64 cargo ship launched at 5:41 p.m. Eastern time July 16 (3:41 a.m. Baikonur time on July 17), carrying three tons of food, fuel and supplies for the residents of the International Space Station. Less than nine minutes after launch, the Progress arrived in its preliminary orbit to begin a two-day journey to the station, where it will automatically dock to the Pirs Docking Compartment on the Earth-facing side of the Russian segment of the outpost July 18, U.S. time. The new Progress will remain docked to the station until mid-January 2017.

YouTube link: [url]https://youtu.be/NDtbfCt2Gcw[/url][/QUOTE]
[YOUTUBE]NDtbfCt2Gcw[/YOUTUBE]
&
[QUOTE]
The Elon Musk Fan Club - Public 46m ago
Elon Musk Retweeted
SpaceX ‏@SpaceX
[QUOTE]All systems go & weather 90% favorable for launch of Dragon to @Space_Station. Liftoff slated for Monday, 12:45am ET[/QUOTE]
[url]https://twitter.com/SpaceX/status/754474468123156480[/url]
[/QUOTE]

only_human 2016-07-17 04:48

Apollo 11 Guidance Computer (AGC):
[URL="http://qz.com/726338/the-code-that-took-america-to-the-moon-was-just-published-to-github-and-its-like-a-1960s-time-capsule/"]The code that took America to the moon was just published to GitHub, and it’s like a 1960s time capsule[/URL]
[QUOTE]And in the PINBALL_GAME_BUTTONS_AND_LIGHTS.s file, which is described as “the keyboard and display system program … exchanged between the AGC and the computer operator,” there’s a peculiar Shakespeare quote:
[CODE]
# THE FOLLOWING QUOTATION IS PROVIDED COURTESY OF THE AUTHORS
#
# "IT WILL BE PROVED TO THY FACE THAT THOU HAST MEN ABOUT THEE THAT
# USUALLY TALK OF A NOUN AND A VERB, AND SUCH ABOMINABLE AS
# NO CHRISTIAN EAR CAN ENDURE TO HEAR."
# HENRY 6, ACT 2, SCENE 4
[/CODE]
This is likely a reference to the AGC programming language itself, as one Reddit user pointed out. The language used predetermined “nouns” and “verbs” to execute operations. The verb 37, for example, means “Run program,” while the noun 33 means “Time to ignition.”[/QUOTE]

jasong 2016-07-18 02:39

Have any of you ever wondered if Elon Musk smells good?

And do I ever have the urge to attack Sonny's singing partner? ;) :)

only_human 2016-07-18 03:50

Just under an hour until SpaceX launch.

NASA TV is streaming now:
[url]http://www.ustream.tv/nasahdtv[/url]

YouTube will be streaming about 20 minutes before launch
[url]https://m.youtube.com/watch?v=ThIdCuSsJh8[/url]
[YOUTUBE]ThIdCuSsJh8[/YOUTUBE]

chalsall 2016-07-18 03:52

T-53 minutes...
 
[URL="http://www.gizmodo.com.au/2016/07/spacex-to-have-a-busy-night-with-launch-and-experimental-landing/"]SpaceX to attempt another launch (and landing) in about an hours time[/URL]!

I'll be staying up to watch in bed (with ear-phones; my SO doesn't seem to find such things nearly as interesting as I do...).

Mark Rose 2016-07-18 04:54

Touchdown!!

Uncwilly 2016-07-18 05:04

1 Attachment(s)
Did you catch the full launch location?

firejuggler 2016-07-18 16:10

In only_human video, landing start @ around 24:30 . It is anoter success for SpaceX and Elon Musk.

chalsall 2016-07-28 19:36

[URL="http://spacenews.com/spacex-spending-about-300-million-on-red-dragon-mission/"]It must be pretty cool to budget USD $300,000,000....[/URL]

Xyzzy 2016-07-28 23:43

[url]http://arstechnica.com/science/2016/07/apollo-astronauts-dying-of-heart-disease-at-4-5x-the-rate-of-counterparts/[/url]

xilman 2016-07-29 07:34

[QUOTE=Xyzzy;438947][url]http://arstechnica.com/science/2016/07/apollo-astronauts-dying-of-heart-disease-at-4-5x-the-rate-of-counterparts/[/url][/QUOTE]
My first thought, before I'd even clicked on the link was "small number statistics".

The article strongly suggests a link between radiation and cardiovascular defects but warns
[quote]
“Caution must be used in drawing definitive conclusions regarding specific health risks,” they concluded. The astronaut numbers are very small for an epidemiological study, there may be other factors in the space environment that could explain the possible health effects, and the type of radiation given to the mice wasn’t exactly the same as the type astronauts experience.[/quote]

Presumably the similar effects should have been noticed in the hibakusha and those who were in and around Chernobyl. A combined study would have a large sample size.

Mark Rose 2016-07-29 13:51

[QUOTE=xilman;438969]My first thought, before I'd even clicked on the link was "small number statistics".

The article strongly suggests a link between radiation and cardiovascular defects but warns


Presumably the similar effects should have been noticed in the hibakusha and those who were in and around Chernobyl. A combined study would have a large sample size.[/QUOTE]

Yeah, the total amount of radiation the astronauts were exposed to was relatively small. It reminds me of the [url=http://io9.gizmodo.com/i-fooled-millions-into-thinking-chocolate-helps-weight-1707251800]chocolate weight loss study[/url].

I do wonder, however, if there is a similar increased incidence of cardiovascular disease in airline crew, or amongst the residents of the ISS.

Mark Rose 2016-07-29 17:47

[YOUTUBE]SZQY902xQcw[/YOUTUBE]

The best part is the bird tweeting half way through.

xilman 2016-07-29 18:08

[QUOTE=Mark Rose;438979]I do wonder, however, if there is a similar increased incidence of cardiovascular disease in airline crew, or amongst the residents of the ISS.[/QUOTE]Possible, but all those were well inside the magnetosphere, unlike the Apollo crews, and so their radiation exposure isn't much greater than the human norm. Their exposure is also over a long term, again unlike the astronauts in question.

That's why I suggested the populations I did. Short-term exposure to radiation levels much higher than normal.

chalsall 2016-07-29 19:42

[QUOTE=xilman;439004]That's why I suggested the populations I did. Short-term exposure to radiation levels much higher than normal.[/QUOTE]

Which would tend to lead to quicker, and multiple, DNA and RNA damage.

The authors themselves cautioned that the sample size was very small.

I found it interesting that some concluded from this that Mars couldn't be colonized by Humans. Both because of the radiation experienced during the trip from Earth, and the fact that Mars has a tiny magnetosphere.

A strong magnetic field could be generated at relatively low cost during the trip, and actually help provide propulsion. Additional shielding could be provided by products the colonists need to carry with them anyway. Water, for example.

Once on Mars, dig down and live underground. Our early ancestors lived in caves.

Mark Rose 2016-07-29 19:59

Water is a very effective gamma ray absorber. Like, I've stood a few meters away from an active nuclear reactor core. The shielding? Mostly water. Coolest tour I've been on :)

kladner 2016-07-29 21:13

2 Attachment(s)
[QUOTE=Mark Rose;439012]Water is a very effective gamma ray absorber. Like, I've stood a few meters away from an active nuclear reactor core. The shielding? Mostly water. Coolest tour I've been on :)[/QUOTE]
I got to see the [URL="http://reactor.reed.edu/index.html"]research reactor at Reed College[/URL] once. It was a blue glowing area at the bottom of a very large tank of water. We all put on dosimeters before entering the chamber.

chalsall 2016-07-29 21:26

[QUOTE=kladner;439015]It was a blue glowing area at the bottom of a very large tank of water. We all put on dosimeters before entering the chamber.[/QUOTE]

Very cool.

Were you taught why it was glowing blue, and why you were safe?

kladner 2016-07-29 21:48

I was 16 at the time, so I would have known about Čerenkov radiation from years of SciFi reading. However, I'm sure that things were explained. My brother was a student and knew the department head, who personally took us on a tour. I'm pretty sure that my brother was not personally involved with the reactor program.

chalsall 2016-07-29 22:28

[QUOTE=kladner;439020]I was 16 at the time, so I would have known about Čerenkov radiation from years of SciFi reading.[/QUOTE]

Yeah... We youngish were blessed with the deep and informative thinkers and writers like David Brin, Isaac Asimov and Arthur C. Clarke.

kladner 2016-07-30 08:19

[QUOTE=chalsall;439024]Yeah... We youngish were blessed with the deep and informative thinkers and writers like David Brin, Isaac Asimov and Arthur C. Clarke.[/QUOTE]
.....James Blish, Robert A Heinlein (even!).....It was a serious sign of impending maturity when I realized what a sexist, militaristic, insecure guy he was.

chalsall 2016-07-30 16:08

[QUOTE=kladner;439050].....James Blish, Robert A Heinlein (even!).....[/QUOTE]

Yeah... And Larry Niven, Jerry Pournelle, etc, etc, etc... Lots of great (and "Hard Sci-Fi") to expand young minds! :smile:

[QUOTE=kladner;439050]It was a serious sign of impending maturity when I realized what a sexist, militaristic, insecure guy he was.[/QUOTE]

I resonate... I am a huge fan of Dan Simmons, but when I read "Flashback" I realized what a racist red neck he is. Still love most of his work ("Drood" was a huge waste of time though!).

kladner 2016-07-30 16:13

[QUOTE=chalsall;439069]Yeah... And Larry Niven, Jerry Pournelle, etc, etc, etc... Lots of great (and "Hard Sci-Fi") to expand young minds! :smile:



I resonate... I am a huge fan of Dan Simmons, but when I read "Flashback" I realized what a racist red neck he is. Still love most of his work ("Drood" was a huge waste of time though!).[/QUOTE]
That's one by Simmons I have not read. I am really taken aback, hearing about "feet of clay." I had no inkling.

chalsall 2016-07-30 16:27

[QUOTE=kladner;439070]I am really taken aback, hearing about "feet of clay." I had no inkling.[/QUOTE]

I'm not following your reference. "Feet of Clay" by Terry Pratchett was wonderful, but that's probably not what you are referring to. In fact I own all of Pratchett's work (often multiple copies, which I "lend" to others, almost never to see them back again!).

A few more more authors worth mentioning since we're tangenting... William Gibson, Bruce Sterling and Neal Stephenson.

Dubslow 2016-07-30 16:53

[QUOTE=xilman;439004]Possible, but all those were well inside the magnetosphere, unlike the Apollo crews, and so their radiation exposure isn't much greater than the human norm. Their exposure is also over a long term, again unlike the astronauts in question.

That's why I suggested the populations I did. Short-term exposure to radiation levels much higher than normal.[/QUOTE]

[url]https://en.wikipedia.org/wiki/Health_threat_from_cosmic_rays#The_deep-space_radiation_environment[/url]

Wikipedia suggests that ISS exposure is roughly 300x that of the surface, with the Apollo and Skylab missions at roughly ~3x that (or around 800-1000x surface exposure). I wouldn't go so far as to call that "isn't much greater than the human norm", though Apollo missions certainly were very short, limiting the total dosage. ISS and Skylab missions on the order of months, though, would definitely hit at least the 100x your typical annual radiation dose over the course of one mission (and there have been repeat ISS visitors).

Edit: Allow me to add a link to this handy chart (note the logarithmic scale) which among other things indicates that the surface exposure to cosmic radiation is only a very small part of the total surface exposure, thus rendering most of the above post largely meaningless. (Total ISS dosage over a 6 month period is a bit more than 10x the annual US average.)

[url]https://upload.wikimedia.org/wikipedia/commons/e/ef/PIA17601-Comparisons-RadiationExposure-MarsTrip-20131209.png[/url]

kladner 2016-07-30 18:46

[QUOTE=chalsall;439071]I'm not following your reference. "Feet of Clay" by Terry Pratchett was wonderful, but that's probably not what you are referring to. In fact I own all of Pratchett's work (often multiple copies, which I "lend" to others, almost never to see them back again!).

A few more more authors worth mentioning since we're tangenting... William Gibson, Bruce Sterling and Neal Stephenson.[/QUOTE]
Agreed on the last three. Pratchett is less familiar to me. My reference was not to a book, but to Simmons [I]having [/I]feet of clay with regard to attitudes you mentioned. :smile:

only_human 2016-08-10 00:04

[URL="http://arstechnica.com/science/2016/08/spacex-has-shipped-its-mars-engine-to-texas-for-tests/"]SpaceX has shipped its Mars engine to Texas for tests[/URL]
[QUOTE]SpaceX appears to have taken a significant step forward with the development of a key component of its Mars mission architecture. According to multiple reports, during the Small Satellite Conference Tuesday in Logan, Utah, SpaceX President Gwynne Shotwell said the company has shipped a Raptor engine to its test site in MacGregor, Texas. A spokesman confirmed to Ars that the engine has indeed been moved to Texas for developmental tests.

The Raptor is SpaceX's next generation of rocket engine. It may be as much as three times more powerful than the Merlin engines that power its Falcon 9 rocket and will also be used in the Falcon Heavy rocket that may fly in late 2016 or early 2017. The Raptor will power SpaceX's next generation of rocket after the Falcon Heavy, the so-called Mars Colonial Transporter.[/QUOTE]

Uncwilly 2016-08-10 04:46

[QUOTE=only_human;439700][URL="http://arstechnica.com/science/2016/08/spacex-has-shipped-its-mars-engine-to-texas-for-tests/"]SpaceX has shipped its Mars engine to Texas for tests[/URL][/QUOTE]
This pleases me.:retina:

only_human 2016-08-13 18:01

[URL="http://www.theverge.com/2016/8/13/12457228/spacex-falcon-9-launch-landing-how-to-watch-livestream-jcsat-16"]Tonight's SpaceX Falcon 9 rocket launch: start time, live stream, and what to expect[/URL]
[QUOTE]If you find yourself without Saturday night plans this evening, why not enjoy a nice SpaceX launch? The company’s eighth Falcon 9 launch of this year is scheduled to take off tonight from Cape Canaveral, Florida at 1:26AM ET, sending a Japanese communications satellite — called JCSAT-16 — into orbit around Earth. And no SpaceX launch is complete these days without a rocket landing attempt afterward. Just a few minutes after the Falcon 9 takes off tonight, a majority of the vehicle will try to land upright on one of SpaceX’s floating drone ships, "Of Course I Still Love You."[/QUOTE]

chalsall 2016-08-14 00:45

[QUOTE=only_human;439931][URL="http://www.theverge.com/2016/8/13/12457228/spacex-falcon-9-launch-landing-how-to-watch-livestream-jcsat-16"]Tonight's SpaceX Falcon 9 rocket launch: start time, live stream, and what to expect[/URL][/QUOTE]

I plan to say up tonight to watch this in bed (via a LTE connection).

This is after running a bloody good Hash here in Bimshire, and cooking my lovely a hearty "Cheesy Bread" meal after we argued about how many slices of bread were involved with a sandwich.

"I'll have 1 and 1/2 sides, please. Oh, and can I have some vegetables with that?....

only_human 2016-08-14 04:30

Live streaming begins in 55 minutes.
[QUOTE]SpaceX’s Falcon 9 rocket will deliver JCSAT-16, a commercial communications satellite for SKY Perfect JSAT Corporation, to a Geostationary Transfer Orbit (GTO). SKY Perfect JSAT is a leading satellite operator in the Asia-Pacific region and provides high-quality satellite communications to its customers using its fleet of 16 satellites. SpaceX’s Falcon 9 successfully launched JCSAT-14 in May.[/QUOTE]
These days I mainly watch the hosted broadcast. I like seeing the enthusiasm and I don't really miss that many details from the pure technical broadcast.
Hosted:
[url]http://youtu.be/QZTCEO0gvLo[/url]
[YOUTUBE]QZTCEO0gvLo[/YOUTUBE]
It's a little like watching people push up their arms on roller coasters but I kid myself if I think I'm going to really learn much anyway. Everyone is so young and enthusiastic. Priceless.

For the technical webcast:
[url]http://youtu.be/OERDIFnFvHs[/url]
[YOUTUBE]OERDIFnFvHs[/YOUTUBE]

I've had bad luck viewing the Nasa TV HD stream on recent launches on my tablet and it looks like they are not streaming this launch anyway.

Dubslow 2016-08-14 04:38

It will be less than 55 minutes before they start streaming, because 55 minutes is the launch time.

kladner 2016-08-14 04:41

[QUOTE=chalsall;439069] I am a huge fan of Dan Simmons, but when I read "Flashback" I realized what a racist red neck he is. Still love most of his work ("Drood" was a huge waste of time though!).[/QUOTE]
It doesn't look promising. :no:
[URL]https://www.washingtonpost.com/entertainment/books/book-review-flashback-by-dan-simmons/2011/07/19/gIQA62F6lI_story.html[/URL]
Sorry for the extended digression.

only_human 2016-08-14 04:42

[QUOTE=Dubslow;439965]It will be less than 55 minutes before they start streaming, because 55 minutes is the launch time.[/QUOTE]
[STRIKE]Yeah, noted. The stream says that it's going live in 43 minutes now but it should start sooner.[/STRIKE]Streaming now

only_human 2016-08-14 05:15

[QUOTE=only_human;439967][STRIKE]Yeah, noted. The stream says that it's going live in 43 minutes now but it should start sooner.[/STRIKE]Streaming now[/QUOTE]

T - 11

Mark Rose 2016-08-14 05:36

Bullseye!

Dubslow 2016-08-14 05:36

Woo! No live video as yet but images of the landed rocket + operator callouts.

only_human 2016-08-14 05:55

Single engine landing burn as opposed to three engines on previous GTO mission landings.

According to hosted comments it allows more time for maneuvers, is gentler and more tolerant of atmospheric winds -- I wasn't listening closely at the time so I might have gotten the gist slightly wrong.

PS
Webcast over; ended with a small shoutout to Kenny Baker from R2D2, RIP.

Mark Rose 2016-08-14 06:22

[QUOTE=only_human;439972]Single engine landing burn as opposed to three engines on previous GTO mission landings.

According to hosted comments it allows more time for maneuvers, is gentler and more tolerant of atmospheric winds -- I wasn't listening closely at the time so I might have gotten the gist slightly wrong.[/QUOTE]

Yes. A single engine burn does use more fuel, however, which is most likely why it wasn't done previously.

Dubslow 2016-08-14 08:27

As always, a billion trade offs. Substantially easier from an operations and controls standpoint, at the expense of more fuel/delta V being wasted to gravity losses.

Given that JCSAT-16 is nearly identical to JCSAT-14 (rumored to be some 10s of kg less mass) [recall JCSAT-14 produced the "max damage" core being tested to near-destruction], it's kinda surprising that they have the extra margin. Besides switching back to the more costly single engine burn, the press release also listed stage 1 and stage 2 burn times a few seconds shorter each. It's possible they've introduced another minor uprating in Merlin thrust, which might explain the extra margin they apparently had.

chalsall 2016-08-14 17:00

[QUOTE=only_human;439972]Single engine landing burn as opposed to three engines on previous GTO mission landings.[/QUOTE]

I believe this was a single engine *rentry* burn rather than the previous three engine rentry burns. All landing burns have been single engine AFAIU.

Very happy to be corrected.

only_human 2016-08-14 17:20

[QUOTE=chalsall;439990]I believe this was a single engine *rentry* burn rather than the previous three engine rentry burns. All landing burns have been single engine AFAIU.

Very happy to be corrected.[/QUOTE]
Maybe only JCS14 used a three engine landing burn:
[QUOTE]Elon Musk – Verified account ‏@elonmusk

Yeah, this was a three engine landing burn, so triple deceleration of last flight. That's important to minimize gravity losses.
10:51 PM - 5 May 2016[/QUOTE]
[url]https://en.wikipedia.org/wiki/Falcon_9_first-stage_landing_tests#Flight_24:_first_return_from_GTO_mission[/url]
[QUOTE]Pursuing their experiments to test the limits of the flight envelope, SpaceX opted for a shorter landing burn with three engines instead of the single-engine burns seen in earlier attempts; this approach consumes less fuel by leaving the stage in free fall as long as possible and decelerating more sharply, thereby minimizing the amount of energy expended to counter gravity.[75] Elon Musk indicated this first stage may not be flown again and will instead be used as a life leader for ground tests to confirm future first stage rockets are good.[76][/QUOTE]

PS:
Reddit: [URL="https://www.reddit.com/r/spacex/comments/4jjovw/mathematical_analysis_of_a_threeengine_hoverslam/"]Mathematical analysis of a three-engine hoverslam[/URL]

Dubslow 2016-08-14 20:31

[QUOTE=chalsall;439990]I believe this was a single engine *rentry* burn rather than the previous three engine rentry burns. All landing burns have been single engine AFAIU.

Very happy to be corrected.[/QUOTE]

There's been multiple three engine landing burns for purposes of efficient use of extremely limited fuel.

Conversely, I can't think of a reason to do a single engine reentry burn (excepting the earlier instances where only one engine had reignition equipment, which hasn't been the case for several launches). For landing, less engines offers greater control, but for reentry the engines contribute little to none of the targeting control, they are merely brakes. (The grid fins are the primary control authority above subsonic speeds.)

chalsall 2016-08-14 21:48

[QUOTE=Dubslow;439998]There's been multiple three engine landing burns for purposes of efficient use of extremely limited fuel.[/QUOTE]

Thanks for the correction. Sincerely.

[QUOTE=Dubslow;439998]Conversely, I can't think of a reason to do a single engine reentry burn (excepting the earlier instances where only one engine had reignition equipment, which hasn't been the case for several launches).[/QUOTE]

One possibility I can think of is to slow the reentry speed over a longer period (applying the breaks slowly) such that the heating experience by the vehicle because of atmospheric interaction is lessened to a defined tolerance envelope while it is falling.

I could, of course, be completely wrong. :smile:

Dubslow 2016-08-15 02:08

[QUOTE=chalsall;439999]
One possibility I can think of is to slow the reentry speed over a longer period (applying the breaks slowly) such that the heating experience by the vehicle because of atmospheric interaction is lessened to a defined tolerance envelope while it is falling.
[/QUOTE]

Heating and stress are related to speed by a square? cube? something like that.

Using less thrust means higher speeds for longer times. The higher the thrust, the less total speed, the less total stress. Yeah it would be shorter, but that's also a good thing. Less stress over less time > more stress over more time.

xilman 2016-08-15 14:39

[QUOTE=Dubslow;439998]Conversely, I can't think of a reason to do a single engine reentry burn [/QUOTE]I can, but it's pretty contrived.

Higher tthrust from three engines rather than one means higher g-forces on the structure. If some component is, or has become, weakened sufficiently ...

retina 2016-08-15 15:08

[QUOTE=Dubslow;439998]There's been multiple three engine landing burns for purposes of efficient use of extremely limited fuel.[/QUOTE]Why stop at three? Why not four? Or six? Why not extend that logic to all nine engines?

I guess there are some very good reasons, but I'm not so sure you have touched on them here.

Dubslow 2016-08-15 20:10

[QUOTE=retina;440046]Why stop at three? Why not four? Or six? Why not extend that logic to all nine engines?

I guess there are some very good reasons, but I'm not so sure you have touched on them here.[/QUOTE]
Here's the primary answer:
[QUOTE=xilman;440043]I can, but it's pretty contrived.

Higher tthrust from three engines rather than one means higher g-forces on the structure. [/QUOTE]

The empty mass of the first stage is somewhere around 25 tons (549 while fueled), while all 9 Merlin 1D engines have a thrust around 775 tons. If they use 5% of the remaining fuel for landing operations (it's a ballpark guess), then 3 engines of the 9 will be producing around 5gs of acceleration (775 / 3 / 50), which is generally the structural limit. As the fuel decreases further, they throttle the three engines, then shutdown two and go full thrust on the center engine, and eventually that one throttles down for landing.

Same limitation for the entry burn. More thrust is more efficient fuel use, up to structural loading limits.

Secondary issues include requiring re-igniters for more than three engines, and symmetric thrust requirements will exclude certain engine counts from being usable (if the structural acceleration limit hadn't already been reached). [Given that the center engine is required in any engine use pattern, and the ring around the center has 8-fold symmetry, any even count is automatically eliminated (since it would require an odd number of outer engines). 1, 3, 5 and 9 are the only viable counts (7 might be doable, but it would be far more sensitive to perturbations than 3 I think).]

chalsall 2016-08-15 20:54

[QUOTE=Dubslow;440054]Same limitation for the entry burn. More thrust is more efficient fuel use, up to structural loading limits.[/QUOTE]

Respectfully, I think this analysis is ignoring the variable of the atmospheric drag as a function of altitude (and the associated heating, which is a cubed function to speed).

Surely they're using drag to help the vehicle slow down (at least, here on earth with our thick atmosphere).

[QUOTE=Dubslow;440054]Secondary issues include requiring re-igniters for more than three engines, and symmetric thrust requirements will exclude certain engine counts from being usable (if the structural acceleration limit hadn't already been reached).[/QUOTE]

I didn't realize that the Merlin engines needed to be "armed" with re-igniters. It doesn't surprise me though, thinking about it.

At the end of the day, I'm just a vicarious observer watching in awe what SpaceX is doing, and trying to figure out how they're doing it without any inside information. Thanks to those more knowledgeable sharing. :smile:

only_human 2016-08-16 00:29

I think all the Russian engines used in the US use hypergolic fuel. Those wouldn't need igniters but a Rapid Unplanned Disassembly would be more worrisome.
[URL="http://www.pbs.org/newshour/rundown/rocket-explosion-releases-toxic-fuel-cloud/"]Russian Rocket Explosion Releases Toxic Fuel Cloud[/URL]
[YOUTUBE]u_UCltkt56w[/YOUTUBE]

Dubslow 2016-08-16 05:05

2 Attachment(s)
[QUOTE=chalsall;440058]Respectfully, I think this analysis is ignoring the variable of the atmospheric drag as a function of altitude (and the associated heating, which is a cubed function to speed).

Surely they're using drag to help the vehicle slow down (at least, here on earth with our thick atmosphere).[/quote]

I think you misunderstand the point of the re-entry burn. Obviously the "most" efficient way to return the booster is to do one and only one landing burn and let drag do what it can before that. But that's about as viable as fitting a ladder into a barn by running at relativistic speeds.

For the simplistic purposes of this post, we can regard the Earth's atmosphere as being essentially zero above ~35-40 km (not strictly true for orbiting and station keeping spacecraft over periods of days months and years, but not a terrible approximation for hypersonic things over the course of a few minutes) and dense below such height. See for example [URL="https://upload.wikimedia.org/wikipedia/commons/9/9d/Comparison_US_standard_atmosphere_1962.svg"]this graph[/URL].

After stage separation for GTO missions, the booster is travelling ~2300 m/s +- 100 m/s. (This is a good time to contemplate that highway speed is ~30 m/s, the speed of sound [at sea level] is ~340 m/s, and this booster velocity is still a ~quarter of LEO regime orbital velocity.) In other words, it is extremely hypersonic.

Were the booster to impact the atmosphere (in the binary approximation described above) at this speed, it would more or less immediately RUD. The aerodynamic and heating forces involved would tear it to bite size shreds in seconds (not unlike, for example, the Columbia orbiter). (In order to survive such forces requires designing a spacecraft's shape entirely around this point of survival -- hence capsules with their blunt bottoms and special materials and the space shuttle with its blunt bottom and special materials.)

The obvious way around this is to slow the booster down from "oh my god running into this wall of air will kill me" to "oh I'll just take a leisurely stroll into this here air". To wit, see the attached graphs (sourced from [URL="https://flightclub.io/results/?id=57b204b7-3a26-4ab5-925f-9ed5d423fbe5&code=JC16"]here[/URL], you will need to play with the scales on the altitude and velocity graphs to get what's below. The data is simulated to best fit post facto data publicly available, primarily from the streams they do). In particular, the speed is roughly halved (more than 1000 m/s delta v!), and the burn lasts from ~70 to ~50 km (varies from mission to mission, [URL="https://www.youtube.com/watch?v=_UFjK_CFKgA"]this video[/URL] mentions 40 km as the shutoff). In fact, you can see from the velocity graph that for a short while after the re-entry burn shuts off, gravity still overpowers drag until roughly ~30 km altitude, after which yes drag does indeed do the majority of the energy dispersion.

At the end of the day, the re-entry burn is never more than the bare minimum it needs to be for the rocket to survive impacting the atmosphere, for precisely the reason of getting best fuel efficiency by using drag. Among other things, the bottom of the rocket is in fact mildly heat-shielded to help reduce the burn time required.

Though this was rather long winded, I hope it was very informative. As a bonus, the site I linked also offers animations of the whole launch (again post facto simulated), see e.g. JCSAT-14 launch [URL="https://flightclub.io/world/?watch=2&code=JC14"]here[/URL] (largely similar launch, payload, and trajectory).
[quote]
I didn't realize that the Merlin engines needed to be "armed" with re-igniters. It doesn't surprise me though, thinking about it.[/QUOTE]

Indeed, in the replay of any SpaceX launch, around T-4 to T-3 or so you can see the green glow of the TEA-TEB hypergolic ignition materials. Given what the public knows about the Merlins requiring individual re-ignition systems onboard, I would hazard to guess that the launch ignition TEA-TEB is provided from the pad itself rather than onboard.

[QUOTE=only_human;440070]I think all the Russian engines used in the US use hypergolic fuel. Those wouldn't need igniters but a Rapid Unplanned Disassembly would be more worrisome.[/QUOTE]
The recent geopolitical issue about Russian sourced engines is exclusively about the [URL="https://en.wikipedia.org/wiki/RD-180"]RD-180[/URL] in use to power ULA Atlas V rockets, and the RD-180 is RP-1/LOX (like SpaceX's Merlin). The Delta rockets use American engines, and as far as I know, Russia has never exported its hypergolic engines (excluding Kazakhstan of course).

xilman 2016-08-16 06:36

:goodposting:

only_human 2016-08-16 06:53

While reading about hypergolic applications earlier today I read about ullage motors. One of them blew up in space on June first.
[URL="http://www.spaceflightinsider.com/organizations/roscosmos/russian-ullage-rocket-engine-explodes-space/"]RUSSIAN ULLAGE ROCKET ENGINE EXPLODES IN SPACE[/URL]
[QUOTE]Ullage motors, like the one that exploded, are used for flight stabilization, altitude control, and propellant settling activities. During a typical Proton flight, a pair of these motors remain attached to the Blok DM-2 and separates when the upper stage’s main engine reaches full thrust.

Each Ullage motor that is installed on a Blok DM-2 upper stage is filled with nitrogen tetroxide (N2O4) and unsymmetrical dimethylhydrazine (UDMH) propellants. This combination causes spontaneous explosions when propellant tanks corrode and these two fuels mix with each other. Under these conditions, such an explosive event could occur years after the rocket was launched, when the corrosion process is well underway.

Explosions of Ullage motors are relatively common. According to Spaceflight101.com, the first such event took place in 1984. This latest break-up is the 45th known explosion of this motor so far.[/QUOTE]
I keep wondering about a vented brown gas Dubslow noticed on a rocket launch. Maybe this ([URL="https://en.wikipedia.org/wiki/Hypergolic_propellant"]hypergolic propellant[/URL])?
[QUOTE]The corrosiveness of nitrogen tetroxide can be reduced by adding several percent nitric oxide (NO), forming mixed oxides of nitrogen (MON).[/QUOTE]
[QUOTE=Dubslow;440086]The recent geopolitical issue about Russian sourced engines is exclusively about the [URL="https://en.wikipedia.org/wiki/RD-180"]RD-180[/URL] in use to power ULA Atlas V rockets, and the RD-180 is RP-1/LOX (like SpaceX's Merlin). The Delta rockets use American engines, and as far as I know, Russia has never exported its hypergolic engines (excluding Kazakhstan of course).[/QUOTE]
Ok. Thanks for the correction.

Dubslow 2016-08-16 07:28

[QUOTE=only_human;440091]While reading about hypergolic applications earlier today I read about ullage motors. One of them blew up in space on June first.
[URL="http://www.spaceflightinsider.com/organizations/roscosmos/russian-ullage-rocket-engine-explodes-space/"]RUSSIAN ULLAGE ROCKET ENGINE EXPLODES IN SPACE[/URL][/QUOTE]

That's cool, I've never heard of things like that. I suppose the greatest risk is adding more debris to what is effectively already a (lethal) junkyard.

kladner 2016-08-16 14:48

Many thanks for the detailed explanation, Dubslow.


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