Phoenix - spring images, HiRISE views of Phoenix after the long, long winter |
Phoenix - spring images, HiRISE views of Phoenix after the long, long winter |
Oct 26 2009, 02:14 PM
Post
#1
|
|
Solar System Cartographer Group: Members Posts: 10166 Joined: 5-April 05 From: Canada Member No.: 227 |
Doug just said in another thread that he was looking for Phoenix in the new images and couldn't find it. Well, I love a challenge. So here it is:
Close-up: (REMOVED - SEE LATER POST) Context: (REMOVED - SEE LATER POST) Note that map-projected HiRISE images at this latitude are in polar stereographic projection, not a cylindrical projection. North is at the left. You might not believe this, but by blinking layers like Clyde Tombaugh I think I can match numerous points, not just the hardware. EDIT: I was a bit off. Correct locations are shown below. Phil -------------------- ... because the Solar System ain't gonna map itself.
Also to be found posting similar content on https://mastodon.social/@PhilStooke Maps for download (free PD: https://upload.wikimedia.org/wikipedia/comm...Cartography.pdf NOTE: everything created by me which I post on UMSF is considered to be in the public domain (NOT CC, public domain) |
|
|
Jan 12 2010, 03:57 AM
Post
#61
|
|
Member Group: Members Posts: 691 Joined: 21-December 07 From: Clatskanie, Oregon Member No.: 3988 |
|
|
|
Jan 12 2010, 09:31 AM
Post
#62
|
|
Rover Driver Group: Members Posts: 1015 Joined: 4-March 04 Member No.: 47 |
That January Hirise image is stunning, with that combination of frost and land.
|
|
|
Jan 12 2010, 02:00 PM
Post
#63
|
|
Senior Member Group: Members Posts: 2921 Joined: 14-February 06 From: Very close to the Pyrénées Mountains (France) Member No.: 682 |
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/ -------------------- |
|
|
Guest_Sunspot_* |
Jan 12 2010, 04:56 PM
Post
#64
|
Guests |
|
|
|
Jan 12 2010, 05:29 PM
Post
#65
|
|
Junior Member Group: Members Posts: 53 Joined: 5-October 06 Member No.: 1227 |
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. |
|
|
Jan 12 2010, 06:03 PM
Post
#66
|
|
Junior Member Group: Members Posts: 56 Joined: 6-September 05 From: Paderborn, Germany Member No.: 484 |
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.
-------------------- --- Under Construction ---
|
|
|
Jan 12 2010, 06:13 PM
Post
#67
|
|
Senior Member Group: Members Posts: 2517 Joined: 13-September 05 Member No.: 497 |
Does anyone know what makes using the radio receiver non-zero cost to operate? 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. -------------------- Disclaimer: This post is based on public information only. Any opinions are my own.
|
|
|
Jan 12 2010, 06:26 PM
Post
#68
|
|
Forum Contributor Group: Members Posts: 1372 Joined: 8-February 04 From: North East Florida, USA. Member No.: 11 |
The 18th sounds like a good day to me, as it's my 7th Wedding Anniversary . woot !
|
|
|
Jan 12 2010, 06:33 PM
Post
#69
|
|
Member Group: Members Posts: 507 Joined: 10-September 08 Member No.: 4338 |
Is the remaining frost at this point CO2 or H20?
|
|
|
Jan 12 2010, 07:10 PM
Post
#70
|
|
Senior Member Group: Members Posts: 1431 Joined: 26-July 08 Member No.: 4270 |
Imagine how it would look from Phoenix Hopefully we'll have images in the not-too-distant future. -------------------- -- Hungry4info (Sirius_Alpha)
|
|
|
Jan 12 2010, 10:24 PM
Post
#71
|
|
Director of Galilean Photography Group: Members Posts: 896 Joined: 15-July 04 From: Austin, TX Member No.: 93 |
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.
-------------------- Space Enthusiast Richard Hendricks
-- "The engineers, as usual, made a tremendous fuss. Again as usual, they did the job in half the time they had dismissed as being absolutely impossible." --Rescue Party, Arthur C Clarke Mother Nature is the final inspector of all quality. |
|
|
Jan 13 2010, 12:14 AM
Post
#72
|
|
Senior Member Group: Members Posts: 2517 Joined: 13-September 05 Member No.: 497 |
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. 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. -------------------- Disclaimer: This post is based on public information only. Any opinions are my own.
|
|
|
Jan 13 2010, 03:28 PM
Post
#73
|
|
Martian Photographer Group: Members Posts: 352 Joined: 3-March 05 Member No.: 183 |
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. |
|
|
Jan 13 2010, 03:51 PM
Post
#74
|
|
Director of Galilean Photography Group: Members Posts: 896 Joined: 15-July 04 From: Austin, TX Member No.: 93 |
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?
-------------------- Space Enthusiast Richard Hendricks
-- "The engineers, as usual, made a tremendous fuss. Again as usual, they did the job in half the time they had dismissed as being absolutely impossible." --Rescue Party, Arthur C Clarke Mother Nature is the final inspector of all quality. |
|
|
Jan 13 2010, 04:17 PM
Post
#75
|
|
Senior Member Group: Members Posts: 1089 Joined: 19-February 05 From: Close to Meudon Observatory in France Member No.: 172 |
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)... |
|
|
Lo-Fi Version | Time is now: 25th May 2024 - 02:31 PM |
RULES AND GUIDELINES Please read the Forum Rules and Guidelines before posting. IMAGE COPYRIGHT |
OPINIONS AND MODERATION Opinions expressed on UnmannedSpaceflight.com are those of the individual posters and do not necessarily reflect the opinions of UnmannedSpaceflight.com or The Planetary Society. The all-volunteer UnmannedSpaceflight.com moderation team is wholly independent of The Planetary Society. The Planetary Society has no influence over decisions made by the UnmannedSpaceflight.com moderators. |
SUPPORT THE FORUM Unmannedspaceflight.com is funded by the Planetary Society. Please consider supporting our work and many other projects by donating to the Society or becoming a member. |