Monday, April 14, 2008

Phoenix Special > Live Q'n'A with Peter Smith - Principal Investigator



This thread is now closed, time now to return to that nail biting period taking us from here to May 25…spacEurope thanks you all who visited and Peter Smith for his precious time.
41 Days to Mars!

EDITED: Peter Smith will arrive spacEurope at 1800UTC.
Counting from now, 1700UTC and until 1855UTC you can leave your questions to Phoenix Principal Investigator.

As I hope you might have read already, spacEurope will welcome today, April 14, the visit of a very special guest, Phoenix Scout Mission Principal Investigator Peter Smith.

And what is the reason for this presence?
As Phoenix is now, nearly six weeks, 44 days left, on its final stretch towards Mars, we all want to know more about the first mission to reach the planet’s north pole and who better to answer your questions than its Principal Investigator?

If you are a regular visitor of this blog you already know how this Live Q’n’As work.
If it is a first time you can always check the previous one that counted with the participation of Jorge Vago, ExoMars Project Scientist.

You can start participating one hour (1700UTC) before the arrival of our guest, which will arrive here around 1800UTC, I, or other spacEurope crew member, will announce that this same post is now on LIVE mode, then, you can start leaving your questions, wishes, suggestions, etc.

How to proceed?
The easiest way is to enter spacEurope via its main page, there, at the bottom of this same post click where is written 0 (or another number) COMMENTS, click it and you are at Live Q’n’A ground…leave your words in the “leave your comment” section, as time will be limited try to make concise and clear questions, allowing Peter Smith to answer as much requests as possible during the hour (until 1900UTC) he will stay with us.

After doing so you will find a NICKNAME box, you are not obliged to do so but please, identify yourself with a name, use a nickname if you prefer and, if possible, indicate your location (city and country).

Another thing, don’t post or access ANY link in the COMMENTS section and remember to refresh the page from time to time to check for new questions or comments.

In case you have any doubt about how to participate please feel free to send me an e-mail.

Interaction is the word! spacEurope counts with you to make of this occasion a Phoenix celebration!

Onward!

49 comments:

Rui Borges said...

Dear visitors, spacEurope welcomes you to this live Q’n’A with Peter Smith, Phoenix Mission Principal Investigator.
Our guest will only arrive at 1800UTC but this post is now open to your participation.
As time is limited to one hour, try to make concise and clear questions, allowing Peter Smith to answer as much requests as possible.
If even so some questions get unanswered we will try to find a solution for that in the days to come.
I believe spacEurope’s crew member Stuart Atkinson has already something ready for the kick-off so...get yourself comfortable, make of this blog your living room for one hour and...let’s get some answers! ;-)

Stu said...

Thanks Rui... and welcome to everyone already "lurking" here as we wait for Peter to arrive. I'm sure everyone will make him very welcome.

Okay, I'll start the ball rolling with a rather selfish question:

Based on the latest HiRISE data, what features do you expect the Phoenix images to show? Will we see low hills? Mounds? Trenches? Polygonal cracking on the ground? Large boulders? (all the latest "Potential Phoenix landing
site" HiRISE images I've seen look, thankfully, relatively boulder free!)

Stu said...

I've been asked by Doug Ellison - of Unmannedspaceflight.com - to ask some questions too, so here's his first one (which is actually several questions in one):

RA:
How powerful is the arm? Are you worried that the ground may be too
hard to dig any serious trench into? Is it possible that the
spacecraft will get dragged around a little by the actions of the arm?
Will the warmth of the arm melt the ice samples?

Antti said...

Hello, I am Antti "akuo" Kuosmanen from Finland.

Questions:
Peter, using the MOLA camera has been cancelled. Do you think that the MOLA microphone will be used later on in the mission to record some sounds?

How have the ORTs gone? Any challenging or "interesting" scenarios encountered? Have any problems in the operations or spacecraft been found?

Thanks

stu said...

Thanks for your question Antii! Nice to know spacEurope has friends in Finland :-) Peter will be here in less than half an hour or so, so if there's anyone else lurking out there thinking of asking a question, feel free...

akuo said...

Actually when I say MOLA I mean MARDI! The descent camera by MSSS.

Rui Borges said...

I'm already onboard after dealing with the traffic quicker than expected...
Thanks for being such a wonderful MC Stu!
Let's keep on working for a great Q'n'A.

James said...

If there are signs of life over there will Phoenix be able to identify them and how would they be interpreted on Earth to leave us no doubt about what might be discovered?

James

Anonymous said...

First of all, good luck for the mission! Here's my question: If you indeed discover evidence of former life, or even better, current life on mars, how long will it take until the public will be informed? I mean, this would be one of the most important discoveries in the history of science, and I hope it doesn't have to pass certain authorities which might delay the publication.

Best,
Markus from Germany

Rui Borges said...

Hi Markus and James and welcome, Peter Smith must be here soon, in the meanwhile it looks like the life issue is already raising some interesting questions from the audience... ;-)

stu said...

Some GREAT questions already, thanks to everyone who's contributed. Thanks also - in advance - to Peter, for taking the time to come and talk to us. I'm sure he's rather busy, what with planning the most eagerly-awaited space exploration event in a decade, so his visit here is hugely appreciated.

Markus Heinsohn said...

Hi Rui,
after having read 'Postcards from Mars' and 'Life in the Universe' recently, I have to admit that the Pheonix mission has me totally excited.After Mariner 9 in 1971 somewhat lowered the hope for life on Mars, Spirit and Opportunity renewed it, and now Phoenix has the chance to prove what we all have been hoping for! Exciting times.

Best,
Markus from Stade, Germany

Rui Borges said...

Exciting times indeed Markus, this mission may really will truly represent a whole new ground on our knowledge about the Red Planet.
Stay around and get your own question to our PI!

Rui Borges said...

He is just in the lobby checking in... ;-)

Alex said...

This is Alex from Manchester, England.

I have a question about the tones transmitted by Phoenix during EDL. How much information will you gain about Phoenix as it descends and will the data be relayed to Earth in real time or will it be stored by the orbiters and sent after Phoenix lands?

Thanks for spending the time to talk to us and good luck

imipak said...

Greetings everyone, thanks to Peter and the very best luck to the whole team for the 25th! I hope this isn't a FAQ (Rui/admins, delete away if it is:) )

What effect will the hot exhaust from the landing rockets have on the very cold ground that Phoenix will actually land on? In particular, what about the risk of melting near-surface ices?

stu said...

Okay, we have seven questions "on the table" already, so everyone please be patient a few minutes while our guest catches up. :-)

Rui Borges said...

Alex and dear imipak, welcome to spacEurope and thank you for your great questions!
I am sure Peter Smith will be glad to answer as soon as possible!

Seven you say Stu? Here's the 8th...:

When will we get a definitive sign that Phoenix is alive and working, not only communicating?

Markus Heinsohn said...

Markus here again... something I wondered recently: If indeed signs of life are discovered and proven, then how can we rule out that these cells did not have their origin on earth itself? I mean, calculations show that exchange of rock between the inner planets was quite common a while ago.

Best,
Markus from Germany

Peter Smith said...

The robotic arm is 2.35 m long and powerful enough to scrape into hard materials. It is true that if the spacecraft footpad perches on a rock or is otherwise unstable, then the RA has the strength to move the lander. We often joke that landing on ice in low gravity will allow us to pull ourselves along the surface using the RA from rock to rock. If the ice is exceptionally hard we will not dig through it, but instead, will use our RASP to scrape up samples to be delivered to instruments on our deck.

stu said...

Thanks for that first answer Peter, and on behalf of everyone here welcome to spacEurope!

Rui Borges said...

Dear Peter Smith

This was almost as stressing as a landing... ;-)

It is truly a pleasure to count with your presence today here at spacEurope knowing how tight is your schedule must be during this days preceding the landing of Phoenix.
Thank you for the availability and may you enjoy this hour as much as, I am sure, we will.
May this hour be, although a Q’n’A, a great Phoenix celebration!
As you can see there are already some questions on the table from the readers...
Make yourself at home, SpacEurope is yours!

peter Smith said...

The MARDI instrument was found to interfere with the guidance system under rare circumstances forcing the difficult decision to turn it off during the descent. The microphone does work and may be used later in the mission to hear the sounds of the RA scraping on the Martian ice.

Discovering Martian life is beyond the goal of this mission. We are looking first to see if the Martian arctic is habitable: periodic liquid water, organic material (it could be from meteors), and energy sources available for power an organism.

stu said...

Another question from Doug Ellison, Peter:

TEGA/MECA:
How confident are you in the abilities of the atomic force microsocope?
How will you balance the 'limited number of shots' for using TEGA
across multiple trenches, and multiple depths in one trench?

Steve said...

Hi, this is Steve, thank you for answering our questions!
Here is mine:

There is an expected lifetime for the mission, is there the possibility of us being surprised by Phoenix going beyond that?

Markus Heinsohn said...

Hello Peter,

if the discovery of life is not a goal of the mission, could it happen nontheless under extreme lucky circumstances? I mean, who knew the rovers would survive that long ;)

Best,
Markus from Germany

peter Smith said...

On May 25, the lander "feels" the Martian gravity and begins to accelerate toward the planet. Its speed increases from 6000 to 12,500 mph. Fifteen minutes before entry, the lander separates from the cruise stage that have been its life support system for the last 10 months since launch. Seven minutes before landing, we enter the upper atmosphere and the aeroshell experiences the heat of friction with the thin atmosphere. We must enter within a degree of our proper angle or else we can skip off into space or heat too rapidly and overwhelm our protection systems.

After the aeroshell has slowed us to 900 mph, the parachute is deployed and we start a leisurely descent to about 1 km above the surface. At a speed of 150 mph, the spacecraft is released from the backshell and drops toward the surface. Twelve thruster ignite and using radar for guidance bring us to our landing site at a speed of 5 mph. the specially designed landing legs take up the shock of landing. Fifteen minutes later the solar arrays deploy and the camera starts taking images. Our mission begins.

akuo said...

Hi Peter! Thanks for answers. Here is another question:
How many hours can Phoenix operate in a sol? The summer solstice is close to the time of the landing, so there should be plenty of sunlight.

Markus Heinsohn said...

Peter,

will there be some sort of live-stream for the landing? Something like a news-ticker, maybe on nasa.org?

Regards,
Markus

Peter Smith said...

The first week of the mission consists of taking images and preparing for gathering samples. At the end of the first week we expect to have delivered a surface sample to our TEGA instrument. The summer is our prime science opportunity and we expect to meet all our mission goals by September. As you might expect, the mission will continue longer than this up until solar conjunction in mid-November. Recovering operations after that in late December will be very difficult as the Sun is setting in this high arctic region. By February we expect that carbon dioxide ice is forming a thick layer around the lander and without heat Phoenix will not survive. No 4 year mission for us.

peter Smith said...

There will be live coverage on the NASA station during the landing. I hope that you can all find a way to view it in person, this will be a thrilling part of the mission. If you do not subscribe to the NASA channel it can be obtained over the web, through www.nasa.gov. Our project we page is also a good source of information phoenix.lpl.arizona.edu.

Rui Borges said...

Dear visitors

Let us wait for our guest to catch up with the already posted questions in order to prevent some confusion.

I'm loving it, aren't you guys? :-)

imipak said...

(redundant question deleted. Oops! )

The MER computer system runs a varient of the Wind River real-time OS. What does Phoenix use? And a related question: how much reuse of software is there between missions?

peter Smith said...

The landing site has been well imaged from space by the HiRISE camera, a 0.5 m telescope with resolution of rocks 1 - 1.5 m or greater. We have found a safe site with few boulders to insure a safe landing. However, it will not be free of cobbles and smaller pebbles. I am curious to see how these stones have weathered over time and whether they are aligned with the polygonal boundaries.

There are few slopes in the neighborhood and the horizon should look extremely flat, no hills. However, the site is far from boring. We are near a 10 km crater and should be on the ejecta blanket containing material brought to the surface from depth. We are also on the slope of a large volcano, Alba Patera and may encounter ash blown from the interior. Finally, the site is a shallow valley and has undergone erosion which may leave signatures.

Rui Borges said...

OK imipak...I'll let that one go... ;-)

Rui Borges said...

Dear Markus

Your question is on hold.

peter Smith said...

We land just before summer solstice and the first few months of the mission have plenty of sunlight altho our power generation depends on the tilt of the lander which we cannot control. Our science team has many arguments about how ice might react when the overburden of soil is removed. We will try to force some of the ice to melt by putting it in the warmest place we can find--the lander deck, then imaging it as solar heating tries to melt it. The question is will it sublimate before melting?

peter Smith said...

Phoenix uses another variant of the Wind River VXWorks real time OS software, not the same as the MER mission. Missions try to gather as much heritage as possible in their designs--no one wants to start over again from the beginning. However, when new space-qualified computers come available sometimes there is little software heritage to be found.

Rui Borges said...

From Markus:

"Markus Heinsohn said...
Peter,

what will be the next steps after Phoenix has frozen over? I guess future missions depend on the results of phoenix, what is planned if phoenix is a success?

Best of luck,
Markus"

imipak said...

Will there be enough power from the solar panels towards the end of the mission to image CO2 ices accumulating? Are there any "snow-like" behaviours that might be seen - drifts, for instance?

peter Smith said...

We are flying an atomic force microscope built in Switzerland by Urs Staufer for the first time ever. This is a difficult instrument to fly because it is sensitive to vibration even the tiny vibes caused by temperature change and wind. It has worked well in the lab and during environmental tests giving a resolution of an amazing 100 nm per pixel.

Our TEGA instrument which has 8 ovens is used to determine the minerals in the soil and to drive off vapors which are measured in a mass spectrometer. The ovens can only be used once so we must allocate them intelligently. Our basic goal is a surface measurement, an ice sample, and a sample half way between. Then will try to verify that what we have seen is real if the signal are near the noise level.

stu said...

Peter... thanks for the info on what we might see on the ground. Are there plans to image the sky to look for optical effects such as Sun pillars, arcs, haoles and parhelia?

peter Smith said...

Our thruster use hydrazine as fuel, its formula is N2H4 and our ultra-pure mixture has no detectable organics. The combustion products are ammonia and water. The more difficult question is what about the 1% that doesn't combust, it is highly reactive and may alter the chemistry of the surface layers that it contacts. We are vigilant and will try to avoid contaminated areas.

Rui Borges said...

OK, let's wait for Peter Smith to answer these last three questions.

Regarding the AFM you can read about it in a Daniel Parrat excellent work here at spacEurope, you can find the links in this post:
http://spaceurope.blogspot.com/2008/04/phoenix-special-44-days-to-mars-with.html

peter Smith said...

Another major part of our science is the study of polar climate. Not only is Phoenix a traditional weather station, but we use LIDAR, built by our Canadian partners, to measure cloud properties and heights. The camera has special lenses for determining dust opacity and we do look for atmospheric phenomena like dust devils and solar haloes.

The end of the mission has not been carefully studied and there are no guarantees after we complete our primary mission. As much as anything, the NASA budget limits our longevity. We will do everything in our power to last until the last rays of sunlight energize the spacecraft.

All good things come to an end and we will leave important questions for future mission to unravel--Phoenix is a stepping stone on the path to discovering the Truth about Mars.

Good bye all and thank you for your interest!

Rui Borges said...

Well, looks like our time just run out…
Time now to return to that nail biting period taking us from here to May 25…
spacEurope thanks you all who visited and asked and I am sure we all would like to shake our guest’s hands and wish him and his team all the luck for that day.
Feel free to express your thoughts, I am sure Peter Smith and his team will appreciate that from spacEurope.
Personally dear Peter, it was an immense pleasure…only one thing left to say: Onward Phoenix! 

markus Heinsohn said...

Thank you Peter for your time! And thanks Rui for moderating this event :)

Best,
Markus

stu said...

That was a fascinating hour, thanks for organising it Rui, and thanks of course to Peter for sparing us so much of his valuable time. If your question was answered, I hope you're now even more excited about Phoenix having had this "personal involvement" in it! If it wasn't, then I'm sure that between now and Landing day on May 25th we can track down the answer somehow and somewhere.

Rui Borges said...

Your welcome Markus! And don't forget Stuart Atkinson!

Time for us all in Europe to have a great dinner and to let our guest keep on working! 41 days to Mars! :-)