Rosetta & Philae

[Al Skierkiewicz]

I am surprised that no one has started something on this achievement so here goes.
I think that this is one of the most important achievements of recent history. Humans have landed a spacecraft on a foreign body traveling through the solar system at astonishing speed and with such a small gravitational field it produced the kind of problems we find every year in our games.
Reading this morning, the gravitational field of a 4 kM object makes the lander's 200 lb weight equivalent to about 1/30 of an ounce. This required the lander to screw itself into the surface of the comet to hold on. The comet is currently traveling about 23 miles/sec and is 315 million miles from earth. Imagine that! A ship traveling for more than ten years, catches up with an object traveling at 88,00 miles per hour, over 300 milllion miles from Earth and then was able to land on that moving object. Add to that, an unknown surface, temperatures of -70 on the surface and gas escaping constantly in the solar wind.
I can't think of anything but "cool"!

[Sparkyshires]

It's truly inspiring. Also, NASA's first Orion test flight is within a couple weeks! If this flight also goes well, they will use this crew module in future flights to land more people on the moon, asteroids, and even mars.

We're living in a freaking awesome time.

[Taylor]

You can relive the excitement here (through Randal's eyes)

Disclaimer: Expect to lose an hour of your life to this.

[Ether]

Originally Posted by Al Skierkiewicz

Humans have landed a spacecraft on a foreign body traveling through the solar system at astonishing speed

Not to diminish the magnitude of the accomplishment in any way, but Mars is traveling through the solar system far faster than that comet¹.

The accomplish is novel and impressive because of a host of other factors, including but not limited to its size, gravity, terrain, rotation period, and orbit.



¹at the time of landing

[BBray_T1296]

Originally Posted by Ether

Not to diminish the magnitude of the accomplishment in any way, but Mars is traveling through the solar system far faster than that comet¹.

The accomplish is novel and impressive because of a host of other factors, including but not limited to its size, terrain, and orbit.



¹at the time of landing

Not to mention the chained gravity assists!

Earth to solar orbit, earth assist, mars assist, earth assist, asteroid flyby earth assist again, another asteroid flyby, then rendezvous with the comet. Planning a trajectory with 4 assists, 2 flybys, and final orbit in mind over a 12 year period is a very easy thing to screw up

[Chadfrom308]

They had this thing sit silent for 10 years! Then they used gravity to sling them around, then they did some zig zags to slow down, then they landed a little pod on the comet and drilled into it!

I don't even know I am going to eat later on today and these guys planned most of this 10 years ago!

[Ether]

Originally Posted by BBray_T1296

Not to mention the chained gravity assists!

Voyager 1, Galileo, MESSENGER, and Cassini all used multiple gravity assists.

[protoserge]

Hopefully, the solar panels will be able to get sunlight before the electronics freeze. Once that happens, it's likely game over. I don't know the battery life in sleep mode, nor what temperature minimum the electronics can withstand. Has anyone found this information? I know without heaters, current flight hardware lasts only minutes.

On the plus side, useful science data was acquired from Philae and this will give us new insight into comets.

Oh yes, and ESA gets the award for the coolest video associated with the Rosetta mission.

[DonRotolo]

Originally Posted by stinglikeabee

Hopefully, the solar panels will be able to get sunlight before the electronics freeze. Once that happens, it's likely game over. I don't know the battery life in sleep mode, nor what temperature minimum the electronics can withstand. Has anyone found this information? I know without heaters, current flight hardware lasts only minutes.

I can't verify that is true. It has been in a pretty cold part of the solar system (i.e., not on a planet) for a decade or more. The folks at ESA didn't seem concerned about the freeze - they assume it will wake up when it get some sunlight.

Dave might know better though.

[protoserge]

Originally Posted by DonRotolo

I can't verify that is true. It has been in a pretty cold part of the solar system (i.e., not on a planet) for a decade or more. The folks at ESA didn't seem concerned about the freeze - they assume it will wake up when it get some sunlight.

Dave might know better though.

The electronics (including battery) should have been heated during that time. I found out the battery needs to be at 0 degrees C to charge, but haven't found out anything more.

[EricH]

Question for anybody that doesn't mind dating themselves:

Was Philae's landing/surface operations more exciting than Apollo 11? How about inspirational?



I was tracking progress on that mission thinking "This is pretty cool!"

[g_sawchuk]

Well, Apollo 11 was a complete success. Philae however, was not. As stated above, Philae bounced upon landing, (not surprised based off of the speed of the comet) making it land in a place without sunlight, and therefore it has lost power. If the Philae was to somehow make a miracle and complete the goal of the mission, and find the answers of our orgin, then I would classify it as more amazing then Apollo 11. However, if that does not happen, then Apollo 11 was better. After all, Apollo 11 directly involved humans going into space and physically landing on something (the moon).

[Al Skierkiewicz]

Eric,
I am old and don't mind. Apollo 11 was spectacular on many levels. It was, in my opinion, the single greatest technological advancement up to that point during peacetime. Not only had we gone from blowing up rockets on the launch pad to putting three men in multiday missions in less than a decade. Additionally, this was a test that America could "commit itself to achieving the goal, before this decade is out, of landing a man on the moon and returning him safely to the earth." It was a time when we as high school seniors whispered the names of our heroes, Chris Craft, Gene Kranz, Neil Armstrong, Buzz Aldrin and Michael Collins. Yes Gene was and is still a big hero for me. Check out his book "Failure Is Not An Option".
Yes this latest achievement is still a big deal for me. I didn't tear up like I did that July night in 1969 but I was very excited. As FRC builders we should remember that the achievement of getting to a moving object in space after a ten year journey is a test that was passed with flying colors. Additionally, landing on that object that has nearly no gravitational field and still hanging on is a spectacular achievement. Think about it, 1/30 of an ounce is all that the lander had as an equivalent weight. So it bounced, it finally was able to hang on. Remember also that the solar wind is pulling debris off that rock and, as it is likely to be composed of mostly ice, so it is melting as it nears the sun. As that cold rock continues to tumble through our neighborhood, I am betting it will turn towards the sun. It is constantly changing it's COG and I only hope that once the lander gets sunlight it doesn't get blown off in the "wind". I think it's finest hour is yet to come.
And just because I am old doesn't mean that every time a crew member is lost, that I don't think to myself, I still would like to go. I want to be a part of this new frontier even if it means sitting at home and praying that they get there and get home. I am still a part of it and so are you.

[FrankJ]

For Apollo 11, I was at summer camp. The whole camp was allowed to stay up late & watch the landing on what was large at the time color TV. The information that was available "real time" was certainly a lot less. Being in 4th grade at the time, I did not realize the magnitude of the feat. Since the moon race was a much bigger program, I don't think it totally fair to compare them. The concept of systems engineering was largely developed to send people to the moon.

While we were not in a shooting war, the whole moon race thing was driven by the cold war.

[Ether]

Originally Posted by GrifBot

Philae bounced upon landing, (not surprised based off of the speed of the comet)

Please explain why you think the comet's speed was a factor in the bouncing.