Monday, May 26, 2008

Comparison of Phoenix to MRO

Phoenix and MRO are really quite different, in a lot of ways. I attended both launch parties, and would just like to point out some differences in the two spacecraft MOI/landing events.

1. The two landings/MOI took place at about the same time of day, although MRO was on a Friday (Right before spring break).
2. The Phoenix landing was filled with thousands of people pouring into every space they could get. The MRO still had plenty of empty seats in Kuiper Space Sciences largest room.
3. As of MRO MOI, the science team still had 7 months or so to prepare, and was still hiring (Myself included). At Phoenix Landing, the mission will be over in 7 months for sure, lots of pressure is being put on the immediate mission to do as much as possible.
4. MRO's first images took hours to be transmitted. Phoenix only took a few minutes.

So, well, there's just a few things of note between the two missions. Kind of interesting.

Sunday, May 25, 2008

Why Phoenix

Many people have asked, why is the University of Arizona, based in Tucson, AZ, naming a spacecraft Phoenix?

Phoenix, as it now, was built from the Mars Surveyor 2001 Lander. The mission was canceled after the failure of the Mars Polar Lander in late 1999. The two spacecraft were very similar, and NASA decided not to risk another failure. The spacecraft was stored at Lockheed Martin for several years, until a new mission was proposed by Peter Smith, which would use this spacecraft, fix it up, and give it a new mission, namely, to find direct evidence of water ice at the north pole of Mars. It was given the name Phoenix because it was reborn from the ashes of two failed missions, the Mars Polar Lander, and Mars Surveyor Lander.

But, if you are still curious, then Peter Smith will tell you, that an objective is to send Phoenix to Mars.

List of things to come for Phoenix

So, I think we can say now that we are in post-EDL operations, now that the solar panels have been verified. Still on the list of things to come:

1. Full panoramic from Phoenix, I would expect it to be coming in pieces over the next day, every hour and a half or so.
2. Imagery from HiRISE and possible Mars Express, which might show Phoenix while landing. The odds of success are slim, but it sure would be cool!
3. Imagery of HiRISE on it's landing spot. I find this unlikely to come by this Wednesday release, for a few reasons. First of all, it's likely due to a late parachute opening that Phoenix overshot it's landing a bit. If it overshot it far enough, then it would miss a HiRISE window (Remember, the FOV on HiRISE isn't that high...) Secondly, it takes about 4 advanced notice to change an image location, so the next opportunity won't be for a while. Given also the length of a downlink, I put a HiRISE image for the 4th of June.

First Images!

Well, the first images have come in, and the following can be said:

1. The lander landed in a very desolate area, there is hardly a rock to be seen from the pictures.
2. The solar panels deployed successfully.
3. The lander landed in an area with firm ground, it didn't sink in at all, or so it appears.
4. We are still awaiting confirmation of the biocontainer seal being released. Assuming that it happened, we can deploy the arm soon.

I wonder how long it will take to get the lander spotted from Orbit. It looks like if you can find the lander, it'll stand out like a sore thumb, there's absolutely nothing around it, but there's nothing around it to identify it's position, at least from the first image. All you can see is flat landscape for a long ways.


So, Phoenix has now become the 6th US lander to land safely on Mars. Still to be determined is if it is in full working condition. The first picture is expected back in an hour and a half. MRO has attempted with it's HiRISE camera to take a picture, so only time will tell if that has come through. If it was successful, it will be known to the crew in about 7 hours. The deployment stage is being tested, solar planet signals are being received. I'll probably be heading off after this post, so for now, signing off.

Legs seporation and landing

So, the next step is the landing, which will happen soon, likely when I'm writing this post, so I'll explain what's happening. The altitude is now only 1600 meters, and going down. It will very shortly land. 1000 meters. Seporation has been detected, Phoenix is now just on rocket power. 100m 80m 50m 40m 30m 27m 20m 15m waiting for touchdown. Touchdown detected!!!!

Heat shield seporation

They have now confirmed, the heat shield has separated, and parachutes have deployed! Yah!

Awaiting signal

So, while we're awaiting the signal, I might point out a tradition, that the control center passes out peanuts while waiting for such events.

Phoenix should have deployed parachutes by now. BTW, I'm getting all of this info from what I can gather from what they are saying.

Blackout region

We have now entered the atmosphere. We are now in a blackout region, where communication is not expected. So for the next few minutes, there won't necessarily be any updates.


Odyssey and MRO are both in place to receive data. Parachute deployment is expected soon. We are awaiting confirmation. MRO and Odyssey are both relaying data, which is as expected.


Right now we are awaiting confirmation that EDL has started. This starts when Phoenix enters the atmosphere. Right now, we are awaiting this to happen. If all is well, Phoenix should now be on the surface, beaming it's message back to Earth, waiting for the radio waves to return to Earth.
They just announced that radio contact is going as planned, after cruise stage separation. So far, so good.
After trying for almost 20 minutes, I've finally found a seat with my wife, in the back corner of the lobby of Kuiper Space Sciences. I can barely hear what is happening, but they have announced Cruise Stage Separation, which is the final stage of the cruise phase of the mission. EDL starts in only a few minutes.

There is some thousands of people here, I might add.

Phoenix Landing

So, the day has finally come, the Phoenix Lander is going to land on Mars today! The real question is, will it land in one piece? Okay, those of you who know way too much about space will know that an optimal landing will involve several pieces, but you know what I mean.

So, in about 4 and a half hours, Phoenix will enter the Martian atmosphere. At first, it will use a heat shield to protect it against the heat produced by the spacecraft compressing the air in front of it. When it gets closer to the surface, it will eject a supersonic parachute, which should slow it down enough to use a normal parachute. At the same time, it will eject it's heat shield. These both happen about 5 miles above the surface of the planet. Still, both of these parachutes will not be large enough to stop it completely. The atmosphere of Mars is much thinner than that of Earth. Also, you don't want to get tangled up in a parachute, that could be a mess, not to mention cutting the power and imaging capacity of the spacecraft. The parachutes will fly away, along with what is called the backshell, shortly before it will land. Then on board rockets on the Phoenix will take care of the rest of the work, several of them pulsing, and a few more constant.

If all goes well, then Phoenix will call home. This whole process takes about 7 minutes, and is known as the "7 minutes of terror". Everyone who has been working on the spacecraft will be holding their breath, to know if like it's near twin, the Mars Polar Lander, it will fail, or if they managed to fix the problems to have a successful landing. Soon enough, we will all know.