Phoenix mission - Page 5

01101001 · #**121** (**permalink**) 10-July-2007, 01:15 AM

Quote:

Originally Posted by JonClarke

It's not listed in the planetary gazetteer as a formal name. So I assume it is somebody's idea of irony.

I think I may have solved that with the Planetary Society reference above, probably edited in after Andrew Brown replied.

3488 · #**122** (**permalink**) 11-July-2007, 12:55 PM

I am really looking forward to this mission immensely.

It matters not that Phoenix is a static lander. The potential of a first successful landing at a very high latitude on Mars is very exciting. The previous, Viking 2 at 48 North in Utopia, watched as the seasons changed, etc.

Of course with Phoenix, that will not be possible, due to the solar power requirements & the fact that CO2 snow is likely to be about 1 to 2 metres deep, come the Winter / Spring.

Phoenix, assuming & hoping for a successful landing, will answer many first level questions, such as the current hydration levels in high latitude soils, Summer high latitude temperature swings, IR imaging will reveal much about the surface composition, trenching will reveal much about the possible organic chemistry in the surrounding soils.

Regarding pictures. There will undoubtably be many great ones, even if the surface does seem rather featureless from orbital altitudes.

One thing that has not escaped my attention, is that Phoenix will be in the land of the Martian Midnight Sun. I hope that images will be put together to show the Sun approaching, then rising from the northern horizon!!!!

Also there may be some interesting cloud formations & weird atmospheric effects. Hopefully Phoenix may even last well into the Autumn as sunlight will still be fairly plentiful till just before the equinox.

Perhaps we may even witness the accumulation of some CO2 'snow', before the intense cold kills the craft off?

At the Mid Winter Solstice at this site, the Sun does not rise at all, but does come to about 2 degress of the southern horizon at noon. If Phoenix is still alive then, there could be some spectacular atmospheric glows & twilights. It is a moot point, because that cannot happen with Phoenix, but is an interesting thought, or at least I think so anyway.

There are other things that we could all wish for. I would like to see a seismometer added, recording Marsquakes. However that is not included, but that does not mean that I will go off in a sulk & say that Phoenix is a crappy mission.

If everybody had everything included that they wanted, Phoenix will be more like Battlestar Galactica!!!!!! Huge, very heavy, even under the Martian 38% surface gravity, not to mention a huge launcher to launch it from Earth.

Phoenix if successful will be one for the books. It is a great, highly capable craft, the product of dedicated people at JPL / NASA & some of the comments earlier in this thread did seem unrespectful.

I for one & I know Jon Clarke is also, really looking forward to this one.

Image below is the central portion of a MRO HiRISE image of the favoured landing site in Green Valley, Scandia Colles.

Andrew Brown.

01101001 · #**123** (**permalink**) 14-July-2007, 07:22 PM

In the countdown thread:

Quote:

Originally Posted by Kelfazin

So the lander uses rockets to retard its rate at landing, but then it doesn't move. Won't the rockets contaminate the soil it's analyzing?

(Might as well keep the mission discussion here.)

University of Michigan press release: U-M scientists simulate the effects of blowing Mars dust on NASA's Phoenix lander

Quote:

Gusting winds and the pulsating exhaust plumes from the Phoenix spacecraft's landing engines could complicate NASA's efforts to sample frozen soil from the surface of Mars[...]

Renno and U-M doctoral candidate Manish Mehta said there are several concerns about the Phoenix thrusters. They said the supersonic exhaust jets could: buffet the spindly, three-legged probe during the critical final seconds before landing; scour the landing site and strip it of loose soil; and possibly contaminate the martian soil with hydrazine, the liquid fuel used in the thrusters.
"These experiments are mainly run to provide insight to the Phoenix team, so they know what to expect and can somewhat prepare for it," said Mehta, who will use the results in his doctoral dissertation. U-M aerospace engineering senior Neal Rusche and other students from Renno's Multidisciplinary Engineering Design course also are on the team.

3488 · #**124** (**permalink**) 16-July-2007, 03:42 PM

I have heard of this as being a potential problem.

JPL does not think so. The arm probably reaches far enough away to miss any 'blast zone' from the retro rockets.

The only way we will know for sure, is after landing.

Was this a problem with Viking 1 & Viking 2?

Andrew Brown.

01101001 · #**125** (**permalink**) 16-July-2007, 04:29 PM

Quote:

Originally Posted by 3488

Was this a problem with Viking 1 & Viking 2?

Read National Academies of Science Press, Project Openbook, Preventing the Forward Contamination of Mars, p. 148

(I don't get what this source is -- perhaps a machine OCR'd catalog entry for ordering the material. They say it's for search engines and not to cut and paste, so I'll summarize.)

In Viking testing they found a contamination problem, so they redesigned the nozzles to lessen contamination, and that reduced erosion too. Tests showed traces of HCN and that was attributed to a fuel impurity which was eliminated, using purified hydrazine -- used hence, though that still gives small contamination of ammonia, nitrogen, and a bit of water, which must be taken into account.

Seems like there's always some contamination and you test your equipment beforehand to know what to expect.

3488 · #**126** (**permalink**) 16-July-2007, 05:52 PM

Thank you for your reply.

I would have thought as much. As the composition of the fuel of the retrorockets is known, all that needs to be done
is if there is touchdown contamination, just deduct those readings from the total. What is left, is obviously martian.

Relly, that is where a air bag landing would be better, but of course the reach of the arm is given the reason not to use them in this case.

I do not see this contamination issue, being such a big deal.

However, this does not dent my enthusiasm for this mission one bit.

Andrew Brown.

ToSeek · #**127** (**permalink**) 30-July-2007, 03:42 PM

Two articles from Florida Today:

Phoenix to taste Mars water

Quote:

After its launch, cruise through space and suspenseful descent, NASA's Phoenix Mars Lander will do what no other spacecraft has done: drink Martian water.

"We're going to be able to go and, if we're successful at doing it, actually be able to taste the water on another planet," said project manager Barry Goldstein of the Jet Propulsion Laboratory in California.

Entombment would be cool ending for lander

Quote:

If Phoenix Mars Lander survives its primary three-month mission and a whole lot of cold afterward, it may get to witness its own frigid death.

Eventually, the spacecraft will be encased in ice.

01101001 · #**128** (**permalink**) 30-July-2007, 09:27 PM

NASA Ames news release: NASA Scientists to Discuss Phoenix Mission to Mars

Quote:

During a televised mission science briefing originating in Florida, Wednesday, Aug. 1, at about 11:40 a.m. PDT [1440 EDT, 1840 UTC] NASA Ames Research Center will provide local reporters an opportunity to ask questions of NASA scientists about the Phoenix spacecraft's mission to Mars. Phoenix is scheduled to lift off Friday, Aug. 3, from Cape Canaveral Air Force Station, Fla.
[...]
Phoenix scientists available at NASA Ames will be:

Chris McKay, Phoenix co-investigator, biological interpretation, from NASA Ames
Aaron Zent, Phoenix co-investigator, soil-atmosphere interaction, from NASA Ames
Richard Quinn, Phoenix research, NASA Ames and SETI Institute, Mountain View, Calif.
John Marshall, Phoenix co-investigator, soil science, geological studies, SETI Institute, Mountain View, Calif.

Watch NASA TV

01101001 · #**129** (**permalink**) 30-July-2007, 10:51 PM

The Planetary Society's Library for Mars Ready for Launch

Quote:

The Planetary Society's silica-glass DVD is ready to launch to Mars on board Phoenix, NASA's newest Scout mission led by Principal Investigator Peter Smith at the University of Arizona. Attached to the deck of the Phoenix lander, the DVD includes Visions of Mars, a collection of 19th and 20th century stories, essays and art inspired by the Red Planet, as well as the names of over a quarter million inhabitants of Earth. The disk will appear in some of the calibration images that Phoenix sends back from the Martian surface.

"Since The Planetary Society's disk should last for centuries on Mars, we hope astronauts at some future date will enjoy the visionary works we have sent in this first Martian library," said Louis Friedman, Executive Director of The Planetary Society, who conceived the idea for Visions of Mars. "These tales and images have inspired generations about the wonder of space, including many men and women who are now researchers and engineers in the space program."

This first library on Mars contains materials that represent 20 nations and cultures. Visions of Mars includes works by The Planetary Society's co-founder Carl Sagan, Isaac Asimov, Ray Bradbury, Kim Stanley Robinson, Arthur C. Clarke, Percival Lowell and many more.

Cugel · #**130** (**permalink**) 31-July-2007, 03:27 PM

Launch attempt for Friday scrubbed, bad weather preventing second stage fueling.

http://www.spaceflightnow.com/mars/p...16windows.html

01101001 · #**131** (**permalink**) 31-July-2007, 05:40 PM

Quote:

Originally Posted by Cugel

Launch attempt for Friday scrubbed, bad weather preventing second stage fueling.

http://www.spaceflightnow.com/mars/p...16windows.html

That was a table of launch windows.

Oh, here's the news: Mission Status: TUESDAY, JULY 31, 2007

Quote:

Anticipated stormy weather in the Cape Canaveral area this afternoon has caused a ripple effect in preparations to launch the Phoenix lander bound for Mars, forcing NASA to postpone the liftoff aboard a Delta 2 rocket by 24 hours.

Originally set for early Friday, the launch has been rescheduled for Saturday morning. Liftoff will be possible during a pair of one-second launch windows at 5:26 and 6:02 a.m. EDT.

I think I'll put this in the countdown thread, seeing as how it's...

ToSeek · #**132** (**permalink**) 02-August-2007, 02:21 PM

I'd suggest putting launch information in the launch thread and save this thread for general mission information.

01101001 · #**133** (**permalink**) 04-August-2007, 02:58 PM

And, now, after an oh-so-smooth launch, the Phoenix Mission has entered cruise stage.

NASA Phoenix Mars Mission news: Phoenix Heads for Mars, Spacecraft Healthy

Quote:

The Phoenix spacecraft has separated from the Delta II rocket and ground controllers at NASA's Deep Space Network have acquired its signal and begun assessing its health. The solar panels that will power the mission's cruise phase will be deployed and Phoenix will be pointed to best receive solar power and communicate with Earth.

On to a safe Mars entry, descent and landing in May 2008!

...

...

Are we there yet?

01101001 · #**134** (**permalink**) 05-August-2007, 05:55 PM

Quote:

Originally Posted by 01101001

Are we there yet?

Not yet, but in a look forward...

NASA Phoenix Mission, Feature: Helping Phoenix Land

Quote:

"[NASA] Langley's contributions are in a number of areas," said Prasun Desai, senior engineer and Entry, Descent and Landing (EDL) lead engineer. "Our role is to help with the development of the EDL system. We're supporting JPL and Lockheed Martin by defining the requirements for Phoenix's design so that it can meet what it needs to do when it gets to Mars to land safely."
[...]
As Phoenix makes the nine-month journey to Mars, the workload of the Langley engineers will intensify as they prepare for a successful entry, descent and landing -- the period lasting three hours before the spacecraft enters the Mars' atmosphere until it safely reaches the ground.

"Three months before landing is when things will really get busy for us," said Desai.

During the "cruise phase," or Phoenix's flight, Langley will explore different scenarios of possible extreme conditions on Mars to get an idea of how the system will respond. According to Desai, exploring such scenarios enables engineers to fine-tune the system and make it as "robust as possible."

(A tad old, but interesting, but I confess I do this mainly to bump the mission topic above the launch topic.)

01101001 · #**135** (**permalink**) 06-August-2007, 04:27 PM

A new countdown clock!

University of Arizona Phoenix Mars Mission

Landing Countdown:
292 Days 22 Hours 33 Minutes 00 Seconds

RGClark · #**136** (**permalink**) 08-August-2007, 11:22 AM

An archive of Phoenix science and launch news conferences as well as other NASA news conferences is available here:

Space-multimedia.
http://www.space-multimedia.nl.eu.or...&id=1&Itemid=2

Bob Clark

01101001 · #**137** (**permalink**) 08-August-2007, 02:45 PM

University of Arizona Phoenix Mars Mission

Landing Countdown:
291 Days 00 Hours 16 Minutes 00 Seconds

(No. Don't intend to do this frequently. I'm just try to keep this topic more alive than the countdown and launch thread which won't seem to gracefully retire.)

01101001 · #**138** (**permalink**) 10-August-2007, 02:41 AM

Nothing new, really.

University of Arizona Phoenix Mars Mission

Landing Countdown:
289 Days 12 Hours 20 Minutes 00