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-   -   What "weed need" is a space mission! (https://www.mersenneforum.org/showthread.php?t=17609)

Dubslow 2016-10-04 18:51

[QUOTE=chalsall;444238]
SpaceX rarely makes the same mistake twice.[/QUOTE]

[url]http://thecodelesscode.com/case/100[/url]

Dubslow 2016-10-05 00:52

How's this for a headline: Boeing CEO Vows to Beat Musk to Mars

[url]https://www.bloomberg.com/news/articles/2016-10-04/boeing-ceo-vows-to-beat-musk-to-mars-as-new-space-race-beckons[/url]

[quote]“I’m convinced the first person to step foot on Mars will arrive there riding a Boeing rocket,” Muilenburg said at the Chicago event on innovation, which was sponsored by the Atlantic magazine.
[/quote]

LaurV 2016-10-05 07:09

[QUOTE=Dubslow;444257]How's this for a headline: Boeing CEO Vows to Beat Musk to Mars[/QUOTE]
:tu: Competition is always good. I don't really care whose rocket is, if it can bring me there safely... One thing I can not stand, tho... The 12 minutes delay on the internet link when I will access mersenneforum from Mars...

retina 2016-10-05 07:53

[QUOTE=LaurV;444277]The 12 minutes delay on the internet link when I will access mersenneforum from Mars...[/QUOTE]It can be as low as ~six minutes round trip time. Stop complaining.

Dubslow 2016-10-05 07:53

[QUOTE=retina;444282]It can be as low as ~six minutes round trip time. Stop complaining.[/QUOTE]

Or as high as 45! And if you account for going around the Sun, more than an hour!

LaurV 2016-10-05 09:01

Haha, you guys!
(:redface: I accept I didn't look for the real values, just that the number "12" was stuck to my brain from some early movies and articles I read on the web following all this Mars fashion show, so not sure I remembered the right value)

Nick 2016-10-19 09:39

The European Space Agency hopes to land a craft on Mars today.
The current prediction is that it will land at 1428 GMT (Earth time - I don't know what time that is on Mars).

[URL]http://www.esa.int/Our_Activities/Space_Science/ExoMars/Live_updates_ExoMars_arrival_and_landing[/URL]

[URL]http://www.esa.int/Our_Activities/Space_Science/ExoMars/Watch_ExoMars_arrival_and_landing[/URL]

fivemack 2016-10-19 11:52

[QUOTE=LaurV;444289]Haha, you guys!
(:redface: I accept I didn't look for the real values, just that the number "12" was stuck to my brain from some early movies and articles I read on the web following all this Mars fashion show, so not sure I remembered the right value)[/QUOTE]

12 minutes is the semi-major axis of Mars's orbit divided by the speed of light, so the average time it takes for light to get from the Sun to Mars.

[url]https://arxiv.org/pdf/1610.05750[/url] is quite fun - demonstrating that, with the naked eye assisted by a cross-staff made of two rulers one sliding on the other, you can measure angular distances to an accuracy of 0.2 degrees which is more than enough to demonstrate that Mars's orbit is elliptical.

xilman 2016-10-19 17:16

[URL="http://www.bbc.co.uk/news/science-environment-37707776"]Not looking good right now.[/URL] but there's still hope.

Uncwilly 2016-10-19 18:07

[QUOTE=xilman;445385][URL="http://http://www.bbc.co.uk/news/science-environment-37707776"]Not looking good right now.[/URL] but there's still hope.[/QUOTE]
Please check and fix your url.

xilman 2016-10-19 18:09

[QUOTE=Uncwilly;445388]Please check and fix your url.[/QUOTE]Thanks. Seems to work for me now. Cut and paste must have gone wrong

chalsall 2016-10-20 17:55

[QUOTE=xilman;445385][URL="http://www.bbc.co.uk/news/science-environment-37707776"]Not looking good right now.[/URL] but there's still hope.[/QUOTE]

She's dead, Jim.

chalsall 2016-10-20 18:51

If I may please say that anyone who tries this kind of thing are amazing!

NASA's [URL="https://www.youtube.com/watch?v=OHwUrxzrvtg&feature=youtu.be"]Seven Minutes of Terror[/URL] is quite informing.

ESD's [URL="https://www.youtube.com/watch?v=32vlOgN_3QQ"]Ambition[/URL] was pretty cool as well.

The work continues....

MattcAnderson 2016-10-20 21:28

Hi Everybody,

I am very interested in space travel.

Please look at this clickable internet link

[URL]https://en.wikipedia.org/wiki/The_Mysterious_Island[/URL]

It is very interesting and, just so you know Jewels Vern, the author, died in 1905.

Regards
Matt A

PS It is spelled Jules Verne.

chalsall 2016-10-20 21:56

[QUOTE=MattcAnderson;445465]It is very interesting and, just so you know Jewels Vern, the author, died in 1905.[/QUOTE]

Not quite sure what you are trying to say here,

Just so you know, William Gibson nor Neal Stephenson are dead yet.

ewmayer 2016-10-21 00:01

[QUOTE=MattcAnderson;445465][URL]https://en.wikipedia.org/wiki/The_Mysterious_Island[/URL][/QUOTE]

Not sure what the link will tell me that's not covered in the book, which was made into one of the series of 1960s Ray-Harryhausen-stop-motion classics I loved as a kid. (And still enjoy watching.)

[QUOTE]It is very interesting and, just so you know Jewels Vern, the author, died in 1905.[/QUOTE]

IIRC he garnered that nickname because he had a reputation as a ballsy author. Can anyone confirm?

ET_ 2016-10-21 06:58

[QUOTE=ewmayer;445471]Not sure what the link will tell me that's not covered in the book, which was made into one of the series of 1960s Ray-Harryhausen-stop-motion classics I loved as a kid. (And still enjoy watching.)



IIRC he garnered that nickname because he had a reputation as a ballsy author. Can anyone confirm?[/QUOTE]

Wsn't the author Jules Verne?

xilman 2016-10-21 18:17

Splat?
 
[url]http://www.bbc.co.uk/news/science-environment-37731671[/url]

chalsall 2016-10-21 19:33

[QUOTE=xilman;445508][url]http://www.bbc.co.uk/news/science-environment-37731671[/url][/QUOTE]

Few who have had success have never had any failures.

And the ESA orbiter successfully entered orbit and will likely collect valuable data.

We live. We learn.

kladner 2016-10-27 22:09

New hi-rez photo of Europe’s lost Mars lander uncovers a new mystery
 
More: High Res Photos
[url]http://arstechnica.com/science/2016/10/new-hi-rez-photo-of-europes-lost-mars-lander-uncovers-a-new-mystery/[/url]

[QUOTE]It "is unusual for a typical impact event and not yet explained," NASA says.
After NASA's Mars Reconnaissance Orbiter found the landing site of Europe's Schiaparelli lander [URL="http://arstechnica.com/science/2016/10/nasa-has-found-europes-mars-lander/"]last week[/URL], the spacecraft was able to train its High Resolution Imaging Science Experiment camera on the location. On Tuesday, the camera spied three sites where pieces of the lander hit the ground after its descent went awry. NASA [URL="http://www.jpl.nasa.gov/spaceimages/details.php?id=PIA21131"]released[/URL] that photo Thursday.[/QUOTE]

LaurV 2016-11-02 04:57

Now I am curious if Mr. Musk is going to give some porn accessories to the first people going on Mars...

[url]http://www.sciencealert.com/nasa-sent-the-apollo-12-astronauts-into-space-with-porn-on-their-wrists[/url]

xilman 2016-11-11 09:41

But no cigar
 
[URL="http://www.bbc.co.uk/news/science-environment-37940445"]Beagle 2 'was so close to Mars success'[/URL]

Spherical Cow 2016-11-11 16:27

Arggghh. Good article. And what if it did indeed operate for a while, but was unable to send back the data that would indicate life on Mars. Perhaps we've already found life on another planet, but just don't know it. Sort of like that last Mersenne prime that was discovered but went un-reported for months.

Norm

LaurV 2016-11-12 02:26

[QUOTE=Spherical Cow;446989]Arggghh. Good article. And what if it did indeed operate for a while, but was unable to send back the data that would indicate life on Mars. Perhaps we've already found life on another planet, but just don't know it. Sort of like that last Mersenne prime that was discovered but went un-reported for months.

Norm[/QUOTE]
Good point. Let's go and see... :razz:

Dubslow 2017-01-13 18:13

For those of you who more passively follow SpaceX, their return to flight following the September anomaly is [URL="https://www.timeanddate.com/countdown/generic?iso=20170114T095453&p0=4438&msg=Falcon+9+Flight+30&font=sanserif"]scheduled[/URL] for 24 hours from now (subject to weather).

Looking for another successful first stage landing at sea; the second stage will also be doing 3 different burns as it deploys 10 satellites into various polar orbits. Should be a fun one, even without the Return To Flight drama.

chalsall 2017-01-13 19:26

[QUOTE=Dubslow;450892]Looking for another successful first stage landing at sea.[/QUOTE]

Indeed. In this case on "Just read the instructions" in the Pacific, rather than on "Of course I still love you" in the Atlantic.

Humour is such a subjective thing....

xilman 2017-01-13 21:05

[QUOTE=chalsall;450898]Indeed. In this case on "Just read the instructions" in the Pacific, rather than on "Of course I still love you" in the Atlantic.

Humour is such a subjective thing....[/QUOTE][i]A distinct lack of gravitas[/i] is to be located in the Gulf. Or so I heard.

Dubslow 2017-01-14 19:56

Nailed it.

(The 3 burn second stage fact apparently wasn't.)

kladner 2017-02-03 02:28

Congressional analysts worry SpaceX engines are prone to cracks
 
[url]https://arstechnica.com/science/2017/02/report-congressional-analysts-worry-spacex-engines-are-prone-to-cracks/[/url]

Turbine blade cracks, to be exact. Interesting discussion of SpaceX and Boeing's different shortcomings, in the eyes of the US Government Accountability Office.

only_human 2017-02-18 03:48

SpaceX launch
[QUOTE]NASA > Public Feb 17, 6:11 PM

Saturday is launch day! A SpaceX Falcon 9 is being prepped to launch the company’s Dragon spacecraft into orbit carrying about 5,500 pounds of equipment and experiments to the International Space Station. Live coverage begins at 8:30 a.m. EST leading up to liftoff, which is scheduled for 10:01 a.m. Watch: [url]http://www.nasa.gov/live[/url][/QUOTE]

[QUOTE]San Diego Air & Space Museum > Public

SpaceX is hoping to launch from pad 39A in Cape Canaveral for the first time this weekend. In the meantime, watch historical launches from this launchpad! [url]http://ow.ly/zIhG3097uWo[/url][/QUOTE]
[QUOTE]Elon Musk Fan Club > Public Feb 17, 7:21 PM

Elon Musk @elonmusk
Looks like we are go for launch. Added an abort trigger at T-60 secs for pressure decay of upper stage helium spin start system.
[url]https://twitter.com/elonmusk/status/832788691588296705[/url]

Spin start system is used to get the turbopump up to speed before the propellant valves are opened and TEA/TEB injected to ignite it.

[URL="https://www.reddit.com/r/spacex/comments/37lr29/turbopump_startup_sequence/"]Turbopump Start-up Sequence • r/spacex[/URL][/QUOTE]

only_human 2017-02-18 15:08

Launch aborted a little more than 10 seconds to go. Abort phrase "Hold Hold Hold."

Something about the 2nd stage thrust vector control.

The next launch opportunity is tomorrow.
[QUOTE]The Elon Musk Fan Club >Public
Elon Musk ‏@elonmusk

- All systems go, except the movement trace of an upper stage engine steering hydraulic piston was slightly odd. Standing down to investigate.
- If this is the only issue, flight would be fine, but need to make sure that it isn't symptomatic of a more significant upstream root cause
[url]https://twitter.com/elonmusk/status/832970849791537152[/url]

[url]http://jasc-controls.com/jasc-news/jasc-hardware-plays-important-role-in-space-x-launch-to-iss/[/url][/QUOTE]

kladner 2017-02-18 16:36

Ah well. Better an abundance of caution. Remember Challenger. :sad:

Dubslow 2017-02-18 17:55

Musk later tweeted that the system was green but that he personally called the abort to investigate.

kladner 2017-02-18 19:33

[QUOTE=Dubslow;453186]Musk later tweeted that the system was green but that he personally called the abort to investigate.[/QUOTE]
Finding out what was going on is much easier before any possible disaster. Small signs might point to larger faults, as Musk tweeted.

There's more than the cost of the vehicle to lose. Image and reputation are at stake, as well.

chalsall 2017-02-19 18:16

Landing the first stage is almost becoming nominal! :smile: :tu:

kladner 2017-02-19 21:36

I take it, then, that it got successfully aloft. BRAVO!

Dubslow 2017-02-20 06:47

One milestone down, many more to go for 2017.

ewmayer 2017-02-24 02:08

[url=https://arstechnica.com/science/2017/02/nasas-longshot-bet-on-a-revolutionary-rocket-may-be-about-to-pay-off/]NASA’s longshot bet on a revolutionary rocket may be about to pay off[/url] | Ars Technica

Ion propulsion. [Sorry, no Elon Musk future-foo PR-blurbs in this one.]

Dubslow 2017-02-28 02:24

Musk (acting as SpaceX CEO) announced today that SpaceX has received a "significant" deposit from two as-yet anonymous private individuals who have purchased a cislunar free return tourism flight around the moon, to be flown by a Dragon 2 launched aboard a Falcon Heavy, and last approximately a week. The current plan is late 2018, though many of that skeptical timeline for a variety of reasons, not least of which is because Musk mentioned deferring to NASA.

richs 2017-03-09 03:30

Space Tourism
 
[url]http://www.skyandtelescope.com/astronomy-news/spacex-announces-moonshot-mission-2018/?utm_source=newsletter&utm_campaign=sky-mya-nl-170303&utm_content=926395_EDT_SKY_170303&utm_medium=email[/url]

VictordeHolland 2017-03-09 14:08

NASAs plan for an Europa lander:
[URL]https://arstechnica.com/science/2017/03/inside-nasas-daring-8-billion-plan-to-finally-find-extraterrestrial-life/[/URL]

Uncwilly 2017-03-09 15:36

[QUOTE=VictordeHolland;454532]NASAs plan for an Europa lander:
[URL]https://arstechnica.com/science/2017/03/inside-nasas-daring-8-billion-plan-to-finally-find-extraterrestrial-life/[/URL][/QUOTE]
[FONT="Courier New"][CENTER]ALL THESE WORLDS
ARE YOURS EXCEPT
EUROPA
ATTEMPT NO
LANDING THERE
USE THEM TOGETHER
USE THEM IN PEACE[/CENTER][/FONT]
[CENTER]:leaving::no::buddy::max:[/CENTER]

kladner 2017-03-09 17:49

[QUOTE=richs;454516][URL]http://www.skyandtelescope.com/astronomy-news/spacex-announces-moonshot-mission-2018/?utm_source=newsletter&utm_campaign=sky-mya-nl-170303&utm_content=926395_EDT_SKY_170303&utm_medium=email[/URL][/QUOTE]
From the article-
[QUOTE]Many noted the number of delays the promised Falcon Heavy rocket[SUP]1[/SUP] has already faced. Others took issue with millionaires purchasing a place in history[SUP]2[/SUP] ahead of seasoned astronauts.[/QUOTE]1. Better to find bugs now, than to let bugs blow things later. As most folks here would know, we're talking about a monstrously complex vehicle, which while immensely powerful, is also extremely fragile if conditions get too far out of spec.

2. Those purchased seats help continue the program so that the "seasoned astronauts" will have something to ride in. And, to be really crass, isn't it kind of cool to have willing, [U]paying[/U] [STRIKE][URL="https://en.wikipedia.org/wiki/Guinea_pig"]guinea pigs[/URL][/STRIKE] test subjects? Trying out the equipment first could help preserve the pool of seasoned astronauts, which I believe would all be Soyuz riders at this point.

VictordeHolland 2017-03-10 00:21

[QUOTE=Uncwilly;454534][FONT=Courier New][CENTER]A[FONT=Courier New]ALL THESE WORLDS
ARE YOURS EXCEPT
EUROPA
ATTEMPT NO
LANDING THERE
USE THEM TOGETHER
USE THEM IN PEACE[/FONT][/CENTER]
[/FONT]
[CENTER]:leaving::no::buddy::max:[/CENTER]
[/QUOTE]
The Odyssey book(s) are still on my reading list :book:

Dubslow 2017-03-10 01:04

[QUOTE=kladner;454540]From the article-
1. Better to find bugs now, than to let bugs blow things later. As most folks here would know, we're talking about a monstrously complex vehicle, which while immensely powerful, is also extremely fragile if conditions get too far out of spec.
[/QUOTE]

It's less about finding bugs and more about the fact that development resources are being continually diverted. It was six months away in 2013, and now four years later it's still six plus months away. The two "anomalies" haven't helped, especially when one of those destroyed a pad... not to mention the constant iteration of the base F9.

kladner 2017-03-10 01:47

[QUOTE=Dubslow;454564]It's less about finding bugs and more about the fact that development resources are being continually diverted. It was six months away in 2013, and now four years later it's still six plus months away. The two "anomalies" haven't helped, especially when one of those destroyed a pad... not to mention the constant iteration of the base F9.[/QUOTE]
Still, even a down payment on the ticket price helps the project in one way or another. And, every Falcon 9 flight adds to the knowledge base on the way to Falcon Heavy. It is hard for me to fault Musk when he has already driven so much progress toward space travel.

Dubslow 2017-03-10 02:44

[QUOTE=kladner;454568]Still, even a down payment on the ticket price helps the project in one way or another.[/quote]

Agreed, hard to say no when someone is doing this:

[youtube]https://www.youtube.com/watch?v=8QfSzgV1q5g[/youtube]

[QUOTE=kladner;454568]
And, every Falcon 9 flight adds to the knowledge base on the way to Falcon Heavy. [/quote]

Not much consolation to those paying customers whose revenue generating payloads have been delayed 4 years. At least one cancelled a FH launch contract and moved it to a Russian rocket, and another recently cancelled an F9 payload after 2 years of delays, including another recent delay of several months [*after* their return to flight!]. SpaceX scheduling has a looooonnnnngggg way to go.

[QUOTE=kladner;454568]
It is hard for me to fault Musk when he has already driven so much progress toward space travel.[/QUOTE]
At the end of the day, yes indeed, if you aren't a paying customer waiting in line for missed contractual promises, then no one has *any* right to complain about just how far Musk as moved the industry -- and there's so much still left to accomplish.

kladner 2017-03-10 03:13

[QUOTE=Dubslow;454573]Agreed, hard to say no when someone is doing this: [YouTube vid]

Not much consolation to those paying customers whose revenue generating payloads have been delayed 4 years. At least one cancelled a FH launch contract and moved it to a Russian rocket, and another recently cancelled an F9 payload after 2 years of delays, including another recent delay of several months [*after* their return to flight!]. SpaceX scheduling has a looooonnnnngggg way to go.


At the end of the day, yes indeed, if you aren't a paying customer waiting in line for missed contractual promises, then no one has *any* right to complain about just how far Musk as moved the industry -- and there's so much still left to accomplish.[/QUOTE]
I understand all you say. The delays are frustrating, or, in the cases you mention, deal-breakers.

I do consider some delays justified when there is a prospect of putting people on top of the rocket. As far as that goes, it's not good business practice to blow up multi-million dollar satellites, either.

There is certainly a long way to go. We still have to get some ability at intra-system transport. Ion drives look promising in this area. Interstellar, of course, is pretty fantastical at this point. I grew up with Sci-Fi stories about generational sub-light ships, besides the obligatory trans-light "jump" and "hyper" drives. I don't think interstellar can happen until there are means of extracting resources from space. Some kind of asteroid presence, with the skills it would take to get there and survive, seems like a logical precursor, even to the outer planets.

xilman 2017-03-10 12:04

[QUOTE=kladner;454576]There is certainly a long way to go. We still have to get some ability at intra-system transport. Ion drives look promising in this area. Interstellar, of course, is pretty fantastical at this point. I grew up with Sci-Fi stories about generational sub-light ships, besides the obligatory trans-light "jump" and "hyper" drives. I don't think interstellar can happen until there are means of extracting resources from space. Some kind of asteroid presence, with the skills it would take to get there and survive, seems like a logical precursor, even to the outer planets.[/QUOTE]
Another possibility is to lengthen human lifespan. If we could reasonably expect a healthy life of a million years or more, we probably wouldn't find the concept of a thousand-year journey too daunting. Back in the good old days of ocean navigation many people devoted one percent or more of their lifespan to a single journey.

VictordeHolland 2017-03-10 15:17

[QUOTE=kladner;454576]
There is certainly a long way to go. We still have to get some ability at intra-system transport. Ion drives look promising in this area. Interstellar, of course, is pretty fantastical at this point. I grew up with Sci-Fi stories about generational sub-light ships, besides the obligatory trans-light "jump" and "hyper" drives. I don't think interstellar can happen until there are means of extracting resources from space. Some kind of asteroid presence, with the skills it would take to get there and survive, seems like a logical precursor, even to the outer planets.[/QUOTE]
We're only a 0.7 type civilization on the Kardashev scale. So we've got a long way to go towards galaxy domination. Unless we find wormholes or other 'short-cuts' in physics, intra-star travel is going to take a very loooooooooooong time. Even if there is intelligent space faring life in our galaxy, they might not have found us yet (galaxy is a big place). Maybe they don't find us interesting enough (we're like ants to them). Or they could have some sort of Star Trek like directive to not communicate with species under a threshold (warp capability). Even if life is abundant, intelligent life could be rare (or always wipe themselves out at some point). But my favourite future is Cylons/Borg/AI that wipe their parents out (humans) and go on to dominate the galaxy.

chalsall 2017-03-10 16:24

SpaceX to relaunch an orbital F9.
 
Fingers crossed...

SpaceX plans to launch an [URL="http://www.space.com/36005-spacex-test-fires-rocket-for-march-14-launch.html"]EchoStar 23 satellite on a "flight proven" (read: pre-flown) rocket[/URL] very early Tuesday morning.

xilman 2017-03-10 18:11

[QUOTE=VictordeHolland;454617]We're only a 0.7 type civilization on the Kardashev scale. So we've got a long way to go towards galaxy domination. Unless we find wormholes or other 'short-cuts' in physics, intra-star travel is going to take a very loooooooooooong time. Even if there is intelligent space faring life in our galaxy, they might not have found us yet (galaxy is a big place). Maybe they don't find us interesting enough (we're like ants to them). Or they could have some sort of Star Trek like directive to not communicate with species under a threshold (warp capability). Even if life is abundant, intelligent life could be rare (or always wipe themselves out at some point). But my favourite future is Cylons/Borg/AI that wipe their parents out (humans) and go on to dominate the galaxy.[/QUOTE]Take a look at a recent paper which considers the possibility of [URL="http://buff.ly/2msbChC"]FRB's being leakage from light-sail powered interstellar spacecraft[/URL].

chalsall 2017-03-10 18:54

[QUOTE=xilman;454631]Take a look at a recent paper which considers the possibility of [URL="http://buff.ly/2msbChC"]FRB's being leakage from light-sail powered interstellar spacecraft[/URL].[/QUOTE]

[URL="https://en.wikipedia.org/wiki/The_Mote_in_God's_Eye"]The Mote in God's Eye[/URL] anyone?

We're already considering using this kind of technology to send exploratory robots ourselves in the near future. Why wouldn't others? Very interesting times.

xilman 2017-03-10 19:34

[QUOTE=chalsall;454636][URL="https://en.wikipedia.org/wiki/The_Mote_in_God's_Eye"]The Mote in God's Eye[/URL] anyone?

We're already considering using this kind of technology to send exploratory robots ourselves in the near future. Why wouldn't others? Very interesting times.[/QUOTE]One of the problems with the science in TMiGE is that the leakage, green light if I remember correctly, was visible for a long period of time. The recent paper specifically points out that the rotation of the impelling beam needed to track the spacecraft would result in only brief bursts of radiation being received at most everywhere else. On the other hand, perhaps the green leakage was from a deceleration beam when the craft was closer to the target. I (a) can't remember the source material well enough and (b) haven't performed the analysis of how long the beam is likely to be easily visible from the target solar system.

On the gripping hand, it's most unlikely that a spaceship launched a gigaparsec from us would be directed directly at us to within the requisite nano-arcsec precision so we likely wouldn't see the deceleration beam anyway.

chalsall 2017-03-10 19:59

[QUOTE=xilman;454639]On the gripping hand, it's most unlikely that a spaceship launched a gigaparsec from us would be directed directly at us to within the requisite nano-arcsec precision so we likely wouldn't see the deceleration beam anyway.[/QUOTE]

LOL. I'm impressed; you've actually read the book. I shouldn't be surprised. :smile:

Just to throw this out there... The only planets we humans have so far detected happen to be on our plane (or very close to it; either a transient or a red-blue shift).

xilman 2017-03-10 21:16

[QUOTE=chalsall;454640]Just to throw this out there... The only planets we humans have so far detected happen to be on our plane (or very close to it; either a transient or a red-blue shift).[/QUOTE]There have been observations of microlensing events too. I'm not sure whether any of the dozen or so seen in the Andromeda galaxy are due to planets.

Direct imaging has found a number of planets with orbital planes greatly tilted from our line of site.

Some astrometric observations of stellar proper motion have been explained as planetary perturbations. The most notorious case is that of Barnard's star. I believe that particular case has been mostly discredited but I'm not up to date on the status of other candidates. A quick look at [url]http://en.wikipedia.org/wiki/Methods_of_detecting_exoplanets[/url] suggests that several are believed to plausible or better. That page also has links to other discovery methods suitable for finding highly inclined orbits, some of which have been successful.

Al the above concerns only exo-planets. Personally I believe that Sedna, Pluto and Ceres should also be classified as planets but we seem to have lost that argument for the time being. Assuming Planet-X exists, it will be difficult to claim that it's not a planet, despite having ~10 Earth masses, because it hasn't yet cleared its orbit --- a hypothesis I think is quite likely.

VictordeHolland 2017-03-10 23:06

[QUOTE=xilman;454644]
Al the above concerns only exo-planets. Personally I believe that Sedna, Pluto and Ceres should also be classified as planets but we seem to have lost that argument for the time being. Assuming Planet-X exists, it will be difficult to claim that it's not a planet, despite having ~10 Earth masses, because it hasn't yet cleared its orbit --- a hypothesis I think is quite likely.[/QUOTE]
Poor Pluto :cry:
[quote]in the Solar System, a planet is a celestial body which:

1. is in orbit around the Sun,
2. has sufficient mass to assume hydrostatic equilibrium (a nearly round shape), and
3. has "cleared the neighborhood" around its orbit.
[/quote]If Planet-X is found I hope the IAU change the 3rd requirement to something like:
"
- has a radius of at least 1000km
and
- has a mass of at least 10x10[sup]21[/sup]kg
"
This definition would include Pluto (1,186km, 13x10[sup]21[/sup]kg) and Eris (1,163km, 16.7x10[sup]21[/sup]kg) as planets and would be less vague than 'clearing its neighborhood' .
The same requirements would still be 'high' enough to not make every body orbiting the sun a planet. Ceres and Sedna wouldn't make it to planet status.

For size/mass comparison (some are natural satelites):
Mercury 2,439km radius, 330x10[sup]21[/sup]kg
Moon 1,737km radius, 73.5x10[sup]21[/sup]kg
Europa 1,560km radius, 48x10[sup]21[/sup]kg
Charon 606km radius, 1.5x10[sup]21[/sup]kg
Ceres 473km radius, 0.9x10[sup]21[/sup]kg
[URL]https://en.wikipedia.org/wiki/List_of_Solar_System_objects_by_size[/URL]

Dubslow 2017-03-11 03:52

[QUOTE=chalsall;454621]Fingers crossed...

SpaceX plans to launch an [URL="http://www.space.com/36005-spacex-test-fires-rocket-for-march-14-launch.html"]EchoStar 23 satellite on a "flight proven" (read: pre-flown) rocket[/URL] very early Tuesday morning.[/QUOTE]

That is incorrect. I'm not sure where you read that, but the first reused booster will launch SES-10 in "late March", the launch immediately following EchoStar 23. ES 23 is both a new booster and expendable (sadly).

kladner 2017-03-11 05:47

[QUOTE=chalsall;454636][URL="https://en.wikipedia.org/wiki/The_Mote_in_God's_Eye"]The Mote in God's Eye[/URL] anyone?

We're already considering using this kind of technology to send exploratory robots ourselves in the near future. Why wouldn't others? Very interesting times.[/QUOTE]
Indeed. I do take issue with reference to a planet-based laser array.
[QUOTE]Artist's illustration of a light sail powered by a radio beam (red) generated on the surface of a planet.[/QUOTE]
Unless this "planet" were airless it would not be a good place to run a googley-google watt laser.
However, it has been suggested, by Niven I think, that banks of robotic laser cannons on Mercury would have lots of solar power, and could drive intra-system vessels even pretty far into trans-Jovian space.

He also portrayed their conspiratorial use to burn alien spacecraft sniffing around the edges of the system. But don't worry. They were really bad threatening aliens with much better tech than ours.

Niven also included the [URL="https://en.wikipedia.org/wiki/Bussard_ramjet"]Bussard Ram Jet[/URL] in a number of books.Fascinating concept, but as presented they require [URL="https://en.wikipedia.org/wiki/Magnetic_monopole"]magnetic monopoles. [/URL]These are currently pretty scarce. :smile:

chalsall 2017-03-11 14:55

[QUOTE=Dubslow;454665]That is incorrect.[/QUOTE]

Whoops! My bad. Got things muddled up....

xilman 2017-03-11 18:25

[QUOTE=VictordeHolland;454651]Poor Pluto :cry:
If Planet-X is found I hope the IAU change the 3rd requirement to something like:
"
- has a radius of at least 1000km
and
- has a mass of at least 10x10[sup]21[/sup]kg
"
This definition would include Pluto (1,186km, 13x10[sup]21[/sup]kg) and Eris (1,163km, 16.7x10[sup]21[/sup]kg) as planets and would be less vague than 'clearing its neighborhood' .
The same requirements would still be 'high' enough to not make every body orbiting the sun a planet. Ceres and Sedna wouldn't make it to planet status.

For size/mass comparison (some are natural satelites):
Mercury 2,439km radius, 330x10[sup]21[/sup]kg
Moon 1,737km radius, 73.5x10[sup]21[/sup]kg
Europa 1,560km radius, 48x10[sup]21[/sup]kg
Charon 606km radius, 1.5x10[sup]21[/sup]kg
Ceres 473km radius, 0.9x10[sup]21[/sup]kg
[URL]https://en.wikipedia.org/wiki/List_of_Solar_System_objects_by_size[/URL][/QUOTE]I could make the case, as have many others, that the Moon is a co-orbiting planet. The main argument in favour is that the lunar orbit is everywhere concave to the Sun. AFAIK no other body, including Charon, meets this criterion.

VictordeHolland 2017-03-15 14:58

[QUOTE=xilman;454695]I could make the case, as have many others, that the Moon is a co-orbiting planet. The main argument in favour is that the lunar orbit is everywhere concave to the Sun. AFAIK no other body, including Charon, meets this criterion.[/QUOTE]
True, but the barycenter of Earth-Moon system lies inside the Earth, which speaks in favour of a planet + natural satellite. Pluto-Charon on the other hand could be better described as a binary system, since their barycenter lies between them. I personally think it was premature to demote Pluto to dwarf planet status, before a consensus on the definition of a planet was made. But science should be self correcting, so hopefully as we get a better understanding of other star-systems and their planets the professional astronomers can come up with a better definition.

xilman 2017-03-16 17:15

[URL="http://www.planetary.org/blogs/jason-davis/2017/20170306-trumps-first-nasa-budget.html"]Asteroid redirection mission redirected.[/URL] :sad:

LaurV 2017-03-17 09:53

[QUOTE=xilman;454991][URL="http://www.planetary.org/blogs/jason-davis/2017/20170306-trumps-first-nasa-budget.html"]Asteroid redirection mission redirected.[/URL] :sad:[/QUOTE]
Grrr....

Dubslow 2017-03-17 12:18

[QUOTE=xilman;454991][URL="http://www.planetary.org/blogs/jason-davis/2017/20170306-trumps-first-nasa-budget.html"]Asteroid redirection mission redirected.[/URL] :sad:[/QUOTE]

Tis only a proposal, any budgets must be approved by Congress.

Almost certainly that budget isn't passed as described, but... I wouldn't put too much stock in this Congress either.

Xyzzy 2017-03-17 14:30

[QUOTE=VictordeHolland;454651]Poor Pluto :cry:[/QUOTE][YOUTUBE]5nqT7XrYRPc[/YOUTUBE]

LaurV 2017-03-19 13:37

[QUOTE=Xyzzy;455033][YOUTUBE]5nqT7XrYRPc[/YOUTUBE][/QUOTE]
Haha, Who is this guy? I love him. :w00t:

chalsall 2017-03-19 21:33

[QUOTE=LaurV;455113]Haha, Who is this guy? I love him. :w00t:[/QUOTE]

[URL="https://en.wikipedia.org/wiki/Neil_deGrasse_Tyson"]Neil deGrasse Tyson[/URL]. Think [URL="https://en.wikipedia.org/wiki/Carl_Sagan"]Carl Sagan[/URL] in black skin.

Just by chance I came across [URL="https://www.youtube.com/channel/UCZFipeZtQM5CKUjx6grh54g"]this guy: Isaac Arthur[/URL]. I have absolutely no idea who he is, but he seems to know his stuff and has some production ability behind him.

kladner 2017-03-19 21:37

Tyson also does a more lively job of debunking science deniers than Bill Nye, IMO.

chalsall 2017-03-19 22:01

[QUOTE=kladner;455142]Tyson also does a more lively job of debunking science deniers than Bill Nye, IMO.[/QUOTE]

Bill Nye can also [URL="https://www.youtube.com/watch?v=wvO3zJaNBjs"]stand strong in a debate[/URL].

I have actually watched all 2.5 hours of that debate.

VictordeHolland 2017-03-19 22:14

[QUOTE=LaurV;455113]Haha, Who is this guy? I love him. :w00t:[/QUOTE]
StarTalk, the Cosmos (2014) series :w00t: .

chalsall 2017-03-30 19:24

Historic SpaceX launch...
 
So, in a few hours SpaceX might make history again with another first.

kladner 2017-03-30 20:37

Here's a link or two.
[url]http://www.spacex.com/webcast[/url]
[url]https://arstechnica.com/science/2017/03/live-today-spacex-attempts-to-launch-a-flight-proven-rocket/[/url]
[url]https://www.recode.net/2017/3/30/15115414/how-to-watch-live-stream-spacex-falcon-9-rocket-launch-elon-musk[/url]
[url]http://earthsky.org/space/watch-spacex-rocket-launch-march-2017[/url]
...more or less...

Dubslow 2017-03-30 21:01

If that's how we're gonna do it...

[url]https://www.reddit.com/r/spacex/comments/62aqi7/rspacex_ses10_official_launch_discussion_updates/[/url]

[url]https://forum.nasaspaceflight.com/index.php?topic=42544.0;all[/url]

chalsall 2017-03-30 21:09

[QUOTE=Dubslow;455851]If that's how we're gonna do it...[/QUOTE]

Any objection? :wink:

Dubslow 2017-03-30 21:10

[QUOTE=chalsall;455852]Any objection? :wink:[/QUOTE]

Hah no. Just thought I'd post less news-y sites and more engineering oriented ones :smile:

Edit: Er actually while I'm at it, [URL="https://spaceflightnow.com/2017/03/24/ses-10-flight-preps/"]here's a current livestream[/URL] of the pad tuned into the launch loop (quiet right now). Flash at the standard URL or if you have [c]livestreamer[/c] you can watch at [c]livestreamer https://new.livestream.com/spaceflightnow best[/c]

chalsall 2017-03-30 21:14

[QUOTE=Dubslow;455853]Hah no. Just thought I'd post less news-y sites and more engineering oriented ones :smile:[/QUOTE]

Cool. I usually stream the technical feed and the public feed at the same time, each going into a different ear and a different eye.

I pray to the gods that be that they pull this off!

Dubslow 2017-03-30 21:16

[QUOTE=Dubslow;455853](quiet right now)[/QUOTE]

Right after I said that they ran the prop loading check, and F9 is go for prop load!!

chalsall 2017-03-30 21:36

[QUOTE=Dubslow;455857]Right after I said that they ran the prop loading check, and F9 is go for prop load!![/QUOTE]

Prop is high-grade Kerosene. After that is highly cooled Oxygen.

Coolness...

Dubslow 2017-03-30 21:58

[QUOTE=chalsall;455861]Prop is high-grade Kerosene. After that is highly cooled Oxygen.

Coolness...[/QUOTE]

They're both prop, one is fuel, one is oxidizer (and yes I know that you meant RP-1 is loaded first at T-70, then LOx at T-45).

Also, the webcasts are live!

chalsall 2017-03-30 22:04

[QUOTE=Dubslow;455863]Also, the webcasts are live![/QUOTE]

LOL... It is fun fighting with worthy combatants! You are correct, I was incorrect about prop. Both the fuel and the oxidizer are involved with propulsion.

The webcasts are about to go live; currently they're playing music. :smile:

Edit: And now the webcasts are live.

Dubslow 2017-03-30 22:39

THEY DUNNIT. LAUNCH, LAND, RELAUNCH AND RELAND

only_human 2017-03-30 22:40

I want to hear good news about the fairing recovery too.

firejuggler 2017-03-30 22:41

:smile::xyzzy::smile::shock::shock::shock::whee::whee::whee::whee::whee:
pretty much my reaction.

Uncwilly 2017-03-30 23:36

Welcome to the era of reflight.


:faf::clap::farley::wraithx::ttu:
:retina:
:xyzzy:

Dubslow 2017-03-30 23:59

Fairings have been recovered!!!

Dubslow 2017-03-31 00:18

Livestream of the presser via facebook (I'm using incognito mode) [url]https://www.facebook.com/everydayastronaut/videos/vb.229811153862306/764917663684983/?type=3&theater[/url]

only_human 2017-03-31 01:33

[url]https://mobile.twitter.com/SpaceBrendan/status/847598647072088064[/url]
[QUOTE]Brendan Byrne @SpaceBrendan
Musk: Fairing has thrust control and steerable parachute. In tact fairing half floating in the ocean.
4:57 PM - 30 Mar 2017[/QUOTE]

xilman 2017-04-25 20:31

[URL="http://www.lakematthew.com"]Partial terraforming Mars on a 20-year time scale.[/URL]

Xyzzy 2017-04-30 00:30

[url]https://arstechnica.com/science/2017/04/the-lego-has-landed-new-set-allows-you-to-build-the-moon-rocket/[/url]

LaurV 2017-04-30 05:32

Haha, beautiful! I would buy that!
"Oh heck, bring Michael Collins down to the surface too, if you want."
:rofl:

Dubslow 2017-04-30 10:22

SpaceX launch ~53 minutes after this post. Classified NRO payload, 2nd daytime return to landing site attempt. Right at sunrise too, so should be some epic photographs

Uncwilly 2017-05-01 23:57

[QUOTE=Dubslow;457952]SpaceX launch ~53 minutes after this post. Classified NRO payload, 2nd daytime return to landing site attempt. Right at sunrise too, so should be some epic photographs[/QUOTE]

One day late, but great video
[YOUTUBE]EzQpkQ1etdA[/YOUTUBE]

kladner 2017-05-02 01:09

That they maintain external view of the booster almost constantly is impressive. Do they have a something aloft for the higher altitudes?

Uncwilly 2017-05-02 03:09

There have been long range tracking cameras since Gemini. In the movie Apollo13 you can see an operator getting one set at the beginning of the crowd sequence for the launch.

Dubslow 2017-05-02 06:15

Indeed the excellent views having always been technologically possible; the main reason we haven't seen stuff like this before is because it was the first daytime-without-overcast-clouds RTLS launch.

Harrywill 2017-05-03 05:28

we need is a space mission
 
My Space mission:- I want to find a new living planet in space.


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