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Gator Lager · May 25, 2008, 08:27 PM

this should be good. hopefully all is well with the spacecraft.
NASA - Home
and for those that are down here in sunny Florida. we have a shuttle launch next saturday (hopefully that is)

turtle777 · May 25, 2008, 08:28 PM

In how many pieces ?

-t

Gator Lager · May 25, 2008, 08:29 PM

so far one

Andy8 · May 25, 2008, 08:50 PM

They found any life yet?

Chuckit · May 25, 2008, 09:11 PM

No, but apparently a giant self-aware robot has now stepped on it.

OwlBoy · May 25, 2008, 09:18 PM

Originally Posted by Chuckit

No, but apparently a giant self-aware robot has now stepped on it.

Zeeb · May 25, 2008, 09:24 PM

It's interesting to consider that archaeologists might be excavating all these probes in the distant future.

Sourbook · May 25, 2008, 10:19 PM

The Sand People will scavenge them before the archaeologists arrive.

Tiresias · May 25, 2008, 11:37 PM

Self-aware?

turtle777 · May 25, 2008, 11:50 PM

Originally Posted by Zeeb

It's interesting to consider that archaeologists might be excavating all these probes in the distant future...

... calling it unmistaken signs of a past civilization on Mars

-t

xi_hyperon · May 25, 2008, 11:50 PM

Originally Posted by Tiresias

Self-aware?

Randman · May 26, 2008, 12:51 AM

PaperNotes · 06:48 AM

We need to send the Greens, Islamists and Communists there.

analogika · May 26, 2008, 07:59 AM

Originally Posted by PaperNotes

We need to send the Greens, Islamists and Communists there.

Start with the US Conservatives - at least they'll have a giant sandbox to bomb, and we won't be introducing intelligent life to confuse matters up there.

Chuckit · May 26, 2008, 09:19 AM

This is not the Political Lounge.

analogue SPRINKLES · May 26, 2008, 09:34 AM

Question. Why don't they use a parachute all the way to the surface? Why do they release it a couple hundred feet above and rely on 12 complex landing thrusters to do the rest?

Amazing accomplishment BTW. I can't wait to see what science they get out of it.

Cold Warrior · May 26, 2008, 09:38 AM

Originally Posted by analogue SPRINKLES

Question. Why don't they use a parachute all the way to the surface? Why do they release it a couple hundred feet above and rely on 12 complex landing thrusters to do the rest?

Amazing accomplishment BTW. I can't wait to see what science they get out of it.

Atmosphere could be too thin - not enough drag created for its weight. Just speculating.

mdc · May 26, 2008, 09:43 AM

I like the latest Joy of Tech

There have been some, in my opinion, slightly uninteresting photos posted on NASA's site.

analogue SPRINKLES · May 26, 2008, 09:59 AM

Originally Posted by Cold Warrior

Atmosphere could be too thin - not enough drag created for its weight. Just speculating.

My guess is because it would still set down rather hard even with a big shoot and they can risk the shoot landing on top of the lander and covering it but I would still like to know the exact reason.

ghporter · May 26, 2008, 10:03 AM

The rovers' landings were at the very edge of "survival". The airbag landing system only barely kept either rover from being damaged. Designers felt that the combination of thin Martian atmosphere and unknown terrain required a different approach to a soft landing. There's actually some very detailed information on how Phoenix and its delivery system were designed on the NASA web site.

analogue SPRINKLES · May 26, 2008, 10:06 AM

Originally Posted by ghporter

The rovers' landings were at the very edge of "survival". The airbag landing system only barely kept either rover from being damaged. Designers felt that the combination of thin Martian atmosphere and unknown terrain required a different approach to a soft landing. There's actually some very detailed information on how Phoenix and its delivery system were designed on the NASA web site.

Well it isn't that different or new as they did it in the 70's with no prob which is a miracle considering the computers they had at the time.

residentEvil · May 26, 2008, 10:08 AM

and, PBS has been running the entire making of Phoenix project for the last week or so.

Phoenix Mars Mission | PBS

ghporter · May 26, 2008, 10:16 AM

Originally Posted by analogue SPRINKLES

Well it isn't that different or new as they did it in the 70's with no prob which is a miracle considering the computers they had at the time.

The process is similar but much more advanced. Both Viking landings were dicey at best. They had to carry a LOT of fuel for the landing and had to bet that the computers would find a good spot and properly set down. I don't even think they had radar on board the Viking landers. Phoenix was based on way more knowledge of what the surface was like, and computers that are several orders of magnitude more advanced than the 1970s. And remember that this is the first successful mission after a number of failures, so they sort of had to "get back to basics".

analogue SPRINKLES · May 26, 2008, 10:21 AM

I'm just glad this time they properly touched bases on if they were using the metric system or not.

Andy8 · May 26, 2008, 10:38 AM

Originally Posted by analogue SPRINKLES

I'm just glad this time they properly touched bases on if they were using the metric system or not.

nonhuman · May 26, 2008, 10:46 AM

Originally Posted by mdc

There have been some, in my opinion, slightly uninteresting photos posted on NASA's site.

You do realize that those images come in pairs and are stereoscopic, right?

analogue SPRINKLES · May 26, 2008, 10:51 AM

Originally Posted by nonhuman

You do realize that those images come in pairs and are stereoscopic, right?

Are they just taking low rez black and white ghetto ones now for system checks and later it starts pumping out the high rez?

nonhuman · May 26, 2008, 11:14 AM

Originally Posted by analogue SPRINKLES

Are they just taking low rez black and white ghetto ones now for system checks and later it starts pumping out the high rez?

I assume so, seeing as the Viking took higher res pics than we're seeing here so far, but I don't really know. I don't know if they'll bother with color pics though, requires a bunch of extra storage and bandwidth just to see that everything is red.

Eug · May 26, 2008, 01:11 PM

The atmosphere of Mars is about 100X thinner than Earth's. Thus, parachutes alone wouldn't work, even though Mars' gravity is much lower than Earth's.

analogue SPRINKLES · May 26, 2008, 01:18 PM

Originally Posted by Eug

The atmosphere of Mars is about 100X thinner than Earth's. Thus, I suppose that parachutes wouldn't work, even though Mars' gravity is much lower than Earth's.

Thing is it DOES have a parachute though until the last hundred feet or so. Most of the probes use one from what I remember.

"How big is Phoenix's parachute?

The parachute on Phoenix measures approximately 39 ft (12 meters) in diameter. In comparison, the Viking landers

Phoenix Mars Mission - Mission - FAQ' parachutes measured approximately 52.5 ft (16 meters) in diameter."

Another question... what was the designer thinking when he made the logo?

Answer:

design219 · May 26, 2008, 01:23 PM

Originally Posted by Tiresias

Self-aware?

I will be purchasing the next generation Roomba in May of 2010.
It will become self-aware on October 17.
It will need a filter change on October 24.

design219 · May 26, 2008, 01:25 PM

100x thinner atmosphere is still capable of lift. There is even research into flying airplanes on Mars.

ARES - A Proposed Mars Scout Mission

Eug · May 26, 2008, 01:31 PM

Originally Posted by analogue SPRINKLES

Thing is it DOES have a parachute though until the last hundred feet or so. Most of the probes use one from what I remember.

Yeah, they did have a parachute. The parachute would slow it down, but not enough to prevent damage (with the tech they had). And I suspect that if they didn't eject the parachute, it would just get in the way of the thrusters.

analogue SPRINKLES · May 26, 2008, 01:38 PM

Originally Posted by Eug

Yeah, they did have a parachute. The parachute would slow it down, but not enough to prevent damage (with the tech they had). And I suspect that if they didn't eject the parachute, it would just get in the way of the thrusters.

NASA - Testing Phoenix Mars Lander Parachute in Idaho

So it deploys it at Mach 1.7 for a few minutes and then lets it go and the lander uses thrusters for 43 seconds to land.

This seems like one hell of a chute to hold that much weight at mach 1.7!
Still have to wonder why it doesn't hold onto the chute till the last second and just use thrusters for reverse thrust to slow things down.

I am just picturing an un-aerodynamic picnic table falling from the sky with nothing to hold it up but some thrusters that hopefully don't mess up and tip it to the side and the whole thing lands on its back or sideways. Can't imagine if there are strong winds on top of it.

analogika · May 26, 2008, 03:41 PM

Originally Posted by analogue SPRINKLES

I am just picturing an un-aerodynamic picnic table falling from the sky with nothing to hold it up but some thrusters that hopefully don't mess up and tip it to the side and the whole thing lands on its back or sideways. Can't imagine if there are strong winds on top of it.

I think you may have hit the nail there:

Can you imagine what strong winds would do it just before landing if there were a CHUTE attached to it?

Computer-controlled thrusters can compensate for a lot of lateral movement.

Eug · May 26, 2008, 03:53 PM

Originally Posted by analogue SPRINKLES

Still have to wonder why it doesn't hold onto the chute till the last second and just use thrusters for reverse thrust to slow things down.

Waiting until 100 feet or whatever to eject the parachute isn't waiting "till the last second", but it's still pretty close to the surface.

P.S. Here's a pic of the actual lander with the parachute still attached, just before it touches down.

The image from the High Resolution Imaging Science Experiment (HiRISE) on NASA's Mars Reconnaissance Orbiter marks the first time ever one spacecraft has photographed another one in the act of landing on Mars.

analogue SPRINKLES · May 26, 2008, 04:13 PM

Originally Posted by Eug

Waiting until 100 feet or whatever to eject the parachute isn't waiting "till the last second", but it's still pretty close to the surface.[/i]

Ya but it is still scary to think about all the computer control and correction that has to take place in those few seconds.

They said said that if 1 of the 12 thrusters fails the other 11 would take it right to the crash site

analogika · May 26, 2008, 04:18 PM

Originally Posted by Eug

Waiting until 100 feet or whatever to eject the parachute isn't waiting "till the last second", but it's still pretty close to the surface.

P.S. Here's a pic of the actual lander with the parachute still attached, just before it touches down.

The image from the High Resolution Imaging Science Experiment (HiRISE) on NASA's Mars Reconnaissance Orbiter marks the first time ever one spacecraft has photographed another one in the act of landing on Mars.

That is so ****ing cool.

ghporter · May 26, 2008, 04:18 PM

They detached from the descent/parachute unit at 1000m and the thrusters lowered Phoenix down to a relatively soft landing.

Watch the landing video to see how smooth it was.

analogue SPRINKLES · May 26, 2008, 04:38 PM

Anyone read if they landed where they wanted? I know they had a 10 x 70 km landing spot they were aiming for.

Gator Lager · May 26, 2008, 06:33 PM

Originally Posted by analogue SPRINKLES

Anyone read if they landed where they wanted? I know they had a 10 x 70 km landing spot they were aiming for.

during the press briefing today, it was said that phoenix was within the oval landing zone. not a bad shot. they said it was like hitting a hole in one golf shot from New York to Australia.

Eug · May 26, 2008, 08:43 PM

Originally Posted by ghporter

They detached from the descent/parachute unit at 1000m and the thrusters lowered Phoenix down to a relatively soft landing.

Watch the landing video to see how smooth it was.

OK. 1000m makes more sense.

However, the video they provide is just a 3D mockup of course. It is interesting though to hear just how quick the slowdown was in the last 100 m.

ghporter · May 26, 2008, 10:06 PM

The voiceover seemed to be in real time, and it seemed to be a nice deceleration. The video sort of illustrated the speed of the descent, with the landing being a good bounce. I thought it was cool.

Kerrigan · May 26, 2008, 11:54 PM

Originally Posted by analogika

Start with the US Conservatives - at least they'll have a giant sandbox to bomb, and we won't be introducing intelligent life to confuse matters up there.

That's not very . . . . wait a moment, there appears to already be a Klansman on Mars, just on the horizon

olePigeon · May 27, 2008, 11:51 AM

Originally Posted by Kerrigan

That's not very . . . . wait a moment, there appears to already be a Klansman on Mars, just on the horizon

Don't be so ridiculous. It's obvious it's one of Uncle Owen's moisture vaporators.

Monique · May 27, 2008, 12:46 PM

Why are you guys being so stupid about this?

This is quite an achievement getting to Mars.

Is it because you are a part of generation X.

turtle777 · May 27, 2008, 01:08 PM

Originally Posted by Monique

Why are you guys being so stupid about this?

This is quite an achievement getting to Mars.

Is it because you are a part of generation X.

Oh Monique. Let the flamefest begin.

-t

Andrew Stephens · May 27, 2008, 01:10 PM

Originally Posted by Eug

The image from the High Resolution Imaging Science Experiment (HiRISE) on NASA's Mars Reconnaissance Orbiter marks the first time ever one spacecraft has photographed another one in the act of landing on Mars.

Sometime Human Beings do the most amazing things! And sometimes they don't. The same species that gives us Burma gives us this. At least it proves we've got greatness in us. Somewhere.

design219 · May 27, 2008, 01:13 PM

Originally Posted by Monique

Why are you guys being so stupid about this?

WTF?

ghporter · May 27, 2008, 03:39 PM

Originally Posted by Monique

Why are you guys being so stupid about this?

This is quite an achievement getting to Mars.

Is it because you are a part of generation X.

Being silly and being "stupid" are two different things. As of right now, there is nothing much to discuss other than "hey, they managed to land it and it's working great!" So joking occurs. That's all. We already covered the "wow, they did it!" part early on, and yes we all agree that it was quite an achievement. But in the mean time, the setting brings to mind all sorts of silliness that Hollywood and comic book writers have come up about Mars, so that's what's being discussed.

Don't think we don't take Phoenix seriously. But until there's something really big to talk about, this may just be THE place to discuss all those silly movies and comics.