http://en.wikipedia.org/wiki/Proximity-1_Space_Link_Protocol

It's about as stable as TCP/IP.

This makes sense. So, might Phoenix ping MOD or MRO? Or are either of the two instructed periodically to ping Phoenix?
Basically, we're all waiting. But is our wait passive or active?

Active in either case - they will have to tell MRO / MODY to listen. In Lazerus mode I THINK PHX is sat there waiting for a Proximity 1 Hail. Not sure though.

Per Mark Lemmon, http://www.met.tamu.edu/mars/lazarus.html

"So, Phoenix woke up and checked: safe mode, yes; low power, yes; clock reset to pre-launch, yes; landing sensor deployed, yes. Action: try to wake up on solar power only, at whatever time of sol that solar power was sufficient. When awake, listen for a beacon on the orbiters for 2 hours. Then, sleep for 19 hours, and try again."

So yes, checking on PHX will require active commanding of an orbiter.

Alright, thanks.
Is either orbiter being used at the moment for this? If not, when are there plans to try?

The link referenced in post 34 of this thread says they will try "early next year". I thought I heard January at one point, can't find that link now.

January is what Veronica McGregor told me.

NASA to Check for Unlikely Winter Survival of Mars Lander
"Beginning Jan. 18, NASA's Mars Odyssey orbiter will listen for possible, though improbable, radio transmissions from the Phoenix Mars Lander..."

The release includes a new HiRISE image showing Phoenix hardware with lots of frost, dated January 6. I am having a devil of a time matching up the new image to the previous ones (PSD attached of the four previous ones I stacked to make an animation). The image's page on the HiRISE website does not yet contain any information -- guess they needed to wait till the press release got out. Help! I want to post about this fast but I would really really really like to be able to post a comparison animation flickering among the past views of the lander.

EDIT: Crud, PSD attachment didn't work. GIF attached instead.

Aha, I see what my problem was. I was trying to match the current backshell to the past position of the lander. The image was upside down.

New animation is here.

Well at least one solar panel is still attached. The other looks like it's a different colour. Hopefully not a bad sign. But I'm not sure how to interpret the image.

I have labeled in the attached image what I think could be Phoenix's Solar Panels covered in frost. But I'm not entirely sure.

Click to view attachment

That January Hirise image is stunning, with that combination of frost and land.

One image from jan 6th 2010 here: http://www.spaceflightnow.com/news/n1001/11phoenix/
Found also this quote "Odyssey will first try to listen for Phoenix for three days beginning Jan. 18. The orbiter will fly over Phoenix 30 times next week, monitoring communications frequencies for signals during each pass."

Edited: and, as usual, a much better one from Emily: http://planetary.org/blog/

Imagine how it would look from Phoenix

Does anyone know what the cost/downside is of having Odyssey listening for Phoenix? If there is no cost, why are they waiting until the 18th? Why not start listening immediately whenever Odyssey passes over the Phoenix site? (that way we could determine if Phoenix made it throught the winter as soon as possible and maybe get interesting science results sooner).
Presumably they are delaying the start of the listening and then doing it for only 3 days because using the radio receiver on Odyessey must interfere with other instrumentation or data relay or power consumption or what? Does anyone know what makes using the radio receiver non-zero cost to operate?

Even if Phoenix does not have enought power now to wake up yet, continious listening (assuming it can be done for 'free') would allow us to know *when* Phoenix wakes up (if it ever does which is unlikely) which would be interesting to know.

I don't know what the current sun angle is at daytime on that location, but I suspect it's still to low for Phoenix to produce enough energy to wake up. Especially when the solar panels are still covered with frost.

It has to be sequenced, memory has to be allocated for it, etc. I forget if there are flight rules that require some of the other instruments to be off when the UHF is on due to EMI concerns.

And let me remind you that Odyssey doesn't just listen, it has to "hail" the lander by transmitting.

The 18th sounds like a good day to me, as it's my 7th Wedding Anniversary . woot !

Is the remaining frost at this point CO2 or H20?

Hopefully we'll have images in the not-too-distant future.

The other thing to think about is that the 18th is the earliest an optimist would expect a reponse. Phoenix stopped transmitting at about the same sun angle, on the way to winter, which means that it's batteries were supplying power and probably extended the time she could send. On the way out of winter, the batteries are going to be dead, and so will not be supplying any extra juice to get her signal out. I'm sure her power management hardware actively controls the battery charging, but I'm not sure how much control the software has over that coming up from a completely dead state, ie the power manager circuit might start trickle charging the battery to raise the voltage well before the CPU comes out of reset. In some cases, such as mobile phones, a charged battery is required for the transmitter to work, since the transmitter uses much more instantaneous power than the wall charger can provide. If you read his description, he does state that the lander waits 19 hours between 2 hour listening windows, for Lazarus mode to cycle the listening window across the whole day because the on-board clock would be reset. For that, the batteries do need a charge. So, my expectation is that the lander will need to wait significantly past the Jan. 18th minimum sol altitude to charge up the batteries enough to last through the night.

I'm not convinced of that since the accounts suggest the batteries were dead at wakeup from running heaters overnight. At any rate, the batteries are very likely to be useless from being frozen at zero charge -- http://www.edn.com/blog/1470000147/post/510028451.html -- so I think we will probably not be able to use them. I think PHX can transmit with a dead battery. One could look at when the ODY overflights are relative to when one would expect max power on the panels to figure out what the most likely recovery time would be.

The 2008 use of "Lazarus mode" started when the batteries fully depleted overnight. If the batteries had retained charge through the night thereafter, the 19 hour cycle would have worked--but the batteries depleted repeatedly, resetting the clock, and making all known wake-ups occur in the mid- to late-morning (worst time for UHF overflights). Any spring mission without batteries would start with the same problem; but once (IF) Earth regains control, one can imagine a sequence keeping it awake through mid-afternoon. There would be no overnight data storage: data would be taken prior to a pass and sent in the afternoon, and anything after the last pass would be forgotten. And a functioning spacecraft might not have functioning instruments--surviving a couple likely failure modes does not imply surviving all. (Not too mention my take on the HiRISE images, especially August, does not lead to optimism.)

Still, best case is that there could be some repetitive imaging and MET data, and that would be quite cool. If it comes back, I'd expect (my guesses only) that an especially close late morning overflight might see the first signal; that it would take effort to get a sequence loaded, but another favorable overflight would do it; that science content for the sequence would follow later, and would be repetitive. While trying to gain control, each sol's odds would be bad--but time would be on our side, when it was against us in 2008. Also, the lander would be generating a huge amount of engineering data as it tries to wake up each sol, browns out, and then repeats many times until power is sufficient. But the data would not accumulate over sols.

Are there any thoughts on making a lander, or perhaps rover, winter-survivable? Larger batteries with an integrated cutoff at mid-charge to survive a freezing? Solar panel petals on the ground, a la Beagle?

Yes, that was already studied by NASA in the 70's and the Viking Lander was the perfect fit because it was relying for its energy source on RTG's of which the heat was able to be redirected internally to heat some electronics, batteries and components. They only chose not to land a Viking Lander near the poles i.e. (above 75°N), because they thought that the sample boom and collector head would have been unable to retrieve some samples from premafrost (i.e. soil intermixed with ice)...

Yes, there are concepts out there. There are still concepts for short-lived summer missions, too. For a fixed (ie, non-MSL-like) budget you have to trade one capability for another, so the choices will vary according to the proposer's goals.

Are you saying that Phoenix's cameras would more likely to work than the motors that drive them and therefore the cameras might only be able to repeat the last photograph that they took back in 2008?

Am I correct in thinking that the Surface Stereo Imager is currently pointing at the sky. I say this because I think that this is the last photo that that imager ever took:

http://phoenix.lpl.arizona.edu/images.php?...523&cID=377

I think that the Robotic Arm Camera may have been left pointing at something more interesting:

http://phoenix.lpl.arizona.edu/images.php?...206&cID=375

Of course it is possible that these cameras were successfully commanded to turn to something else after taking these pictures and so Surface Stereo Imager repetitive imaging might be more interesting?

One principle that guides my expectations is that if one improbable thing happens, that does not imply all more probable things happen as well. So, the if the solar panels and all other critical path elements work, anything else might still fail. If the CCDs and imaging electronics work, the motors might still fail. But I do expect that if we ever take more pictures, we could likely point them. I think that would be critical--the camera is aimed down, fully stowed.

However, a lazarus mission would not allow new sequences each day. Planning for post-sol-151 ops was aimed at one or few repetitive monitoring sequences. First, the work that goes into a lazarus day is more than what a normal day needed, and could requires days on Earth--if the full ops team were restored. Getting a sequence on-board that can be read on wake-up is risky, and frankly a lot can be gained by well-designed repetitive work. Also, much of the onboard infrastructure that made sequencing do-able will not function. Second, the conditions of a lazarus day are poorly determined--when you plan, you do not know if the first activity is at 8 am or 11 am. You might have to wait 3 hours to move the camera without heating, or heat so long you risk damage if you guess wrong. The comm pass might come 5 hours after wake-up or 9 hours after wake-up. The same unknowns apply every day. Frankly, wake-up could happen more than once in a day, with non-graceful shutdowns in between, so you're recovering from an unknown state. Always. Third, any activity done has to be low cost and borrow people from other highly-stressed projects (and some are simply not available). We may not be able to change from what was planned in November 2008; of course, imaging modules are somewhat plug 'n' play (meaning they might change from November, not day-to-day).

So, you might be able to include a small panorama in the sequence--and then see that pan every day. There were more creative ideas floating around, but creative = risky and difficult. I suppose risk tolerance might be a wee bit higher these days... So, things we might see include (over-the-top optimist's list): MET, which would be able to use its own flash, giving PT data for most awake-time; TECP (air); daily RAC rgbn image at Alviss; SSI set (full-frame telltale, frost-spot(s), cal/magnet/illumination target, sky); lidar. Unlike normal ops, the camera is never stowed and never uses a solar filter.

If Phoenix does make it through Lazarus mode, could continuous sunlight during the summer allow for more robust operations? (I know, "I smell a whole lotta 'if' coming off this plan" )

Continuous sunlight could be a game changer, depending on the list of what still works (also, presumably, the success of some proposed mission of opportunity to NASA). Plenty of time to think about that later. Regardless of what's happen ing with comm, there really is no formal contact among the science team--actually, no formal science team any more.

Phoenix website was updated for a first time after a long hiatus:

http://phoenix.lpl.arizona.edu/index.php

So, today's the day!

I've checked the JPL and NASA sites and even the Phoenix Twitter channel and so far there seems to be no news at all.

A fresh (2-3 days old) picture of the landing site would be great to check, how much ice is left that could cover the solar panels. If the situation is similar to the one in the latest HiRise image, then I think it's very unlikely that the lander already produces enough power to communicate.

This person found news. The news is simply, 'We're trying, nothing yet.'
'

Just a short update, for those who don't follow the NASAJPL Twitter channel:

No signal from @MarsPhoenix after 11 listening passes completed Mon./Tues. Odyssey will be "all ears" during 19 more passes this week.

Thank you for the update. One point though, Oddy does hail Phoenix actively though doen't she ?

Oddy? I'm not sure that's an approved nickname here

Yes, ODY hails, while theoretically PHX listens and responds to hails.

I think, this is the last update from NASAJPL until February...

Listening campaign for @MarsPhoenix is over for now, w/ no signal detected. Odyssey will listen again in Feb & March when sun is higher.

For the January attempts, Odyssey was only listening and not hailing.
Odyssey will hail Phoenix during the February and March campaigns.

Is there a source for this information? As best I can tell from this document -- http://trs-new.jpl.nasa.gov/dspace/bitstre...4/1/06-1429.pdf -- PHX will never send without receiving, so ODY listening without hailing is useless.

It's the way the Lazarus mode works. The source is the Phoenix mission team at JPL (originally from Chris Lewicki and Barry Goldstein). The chief telecommunications engineer for the Mars Exploration Program, Chad Edwards, who led the January listening campaign, confirms: "Phoenix's fault mode would have it transmit to any overhead orbiters - without needing to be hailed - during portions of each 2 hr wake-up session (in between 19 hr hibernation periods). We do not need to hail Phoenix to trigger that behavior."

Assuming Phoenix in Lazarus mode initially goes through a "Goundhog Day" state where it wakes up with a clean slate, tries immediately communicating, runs out the battery, and repeats the next day (instead of trying at various times), would the recent attempts to pick up a signal have coincided with the likely transmit times? What is the local time at the PHX site during the ODY passes?

I don't know the details of the passes, but expect they had a reasonably good sampling of local time. It's around a 5AM/PM orbit, but the polar latitude makes many more times accessible. During the mission, it was occasionally possible to use 3 or 4 consecutive ODY passes (every two hours through the afternoon and evening in that case), and that was for a higher bit-rate than would be in play now.

Hmm. 30 passes in ~3 sols would be all or most opportunities--you could get roughly every hour of the sol, with some resampling, with numbers like that.

Right, but each pass only lasts a max of 7-10 minutes, and I don't know what duty cycle of transmission they were using (since I can't find any documentation that such a mode even existed.) Maybe they send tone for a few seconds every few minutes? Mark, do you know anything about this mode?

Having refreshed my memory, I have a bit more info. The first confirmed lazarus communication was sol 154 in a 5:18 AM pass, lasting about 2 minutes. Phoenix was described as being in a mode of continuous communications attempts over 2 hours or until power runs out. The next sol, a signal was seen at 8:20, but was faint (ODY was low in the sky and the path was long). The next sol, the 13:19 pass worked ( 12 minutes!) giving a record of many, many unsuccessful attempts to wake up and a power state that would not survive the night (again). An early AM pass had apparently showed some sort of signal, too. The last signal was detected (without data) at 157/8:24. After that, it was never clear whether the lander was trying to awaken, and failing; awake at unfortunate times; or had entered a particular (permanently) unrecoverable state. So, I think the intent is constant comm for most of 2 hours, which uses many W-hrs, but it may use <10 minute cycles of shorter attempts.

Rumor has it the second ODY search is underway, with ~60 contact attempts this week.

http://www.jpl.nasa.gov/news/news.cfm?release=2010-063

10 down, 50 to go for this month's campaign.

Not much ice in the area now.
http://www.nasa.gov/mission_pages/phoenix/...ix20100226.html

Not going to claim certainty on this, but it really looks to me like the solar panels broke off.

I can read it either way. The fact that there are two white patches just south of where the arrays are would to me at least, infer shadowing by the arrays hiding those areas from sublimation. I THINK I can see something where the arrays should be. I just don't know.