Sep 30 2016
13

“Rare” indeed. It happens more frequently than presidential elections or the Olympics. No one calls those “rare”.

Sep 30 2016
100

In related news, I also get a third September paycheck today! The flying spaghetti monster is looking upon us all with special benevolence. Read more

Sep 29 2016
2

There are no plans at this time for a Rosetta 2. The next step in cometary exploration is Comet Surface Sample Return. That is, we land a spacecraft on the comet nucleus, scoop up some of the silicates and organic materials on the surface, and return them to Earth for study in laboratories. You can do far more with Read more

Sep 29 2016
1

It could happen but the spacecraft will be dead by then. 67P/CG is still moving away from the Sun and it will eventually reach 5.5 AU, beyond the orbit of Jupiter. The solar panels can no longer be pointed once the spacecraft lands, so there will be no power to keep the electronics warm. Electronics are not designed Read more

Sep 29 2016
1

This comet was selected because it was relatively easy to get to. Because comet orbits are so elliptical, it requires a lot of energy change to match orbits with a comet. The closer the perihelion distance (the point in the orbit closest to the Sun) of the comet’s orbit is to the Earth’s orbit, the less energy is Read more

Sep 29 2016
1

No, the landing speed will be 1 meter per second. Walking speed. The comet’s mass is so low that the escape velocity is only 1 meter per second. The maneuver tonight will cancel out most of Rosetta’s horizontal velocity and it will free fall to the surface. That’s why it takes 13 hours to fall 19 km. It’s moving very Read more

Sep 29 2016
1

Was anything learned from this mission that went into planning/software updates to the OSIRIS-REx mission?

Sep 29 2016
2

For one thing, we would have carried a second lander. The U.S. was supposed to provide a lander but it was canceled for bureaucratic reasons. And the Philae lander grew substantially in mass so it used up the mass allocated to the U.S. lander. Also, with more money we could have carried more instruments for scientific Read more

Sep 29 2016
1

i read thet the rotation period of 67P has changed quite a bit over the last two years (i think 20minutes or so?)... was there also a change in the axis itself?

Sep 29 2016
1

We’ve learned a lot more about how a comet behaves. For example, before Rosetta we thought that there were small active areas covering about 1-3% of the surface. We now know that most of the surface is active but at a relatively low level, ~7%. Read more

Sep 29 2016
1

I thought I answered this. The spacecraft will not be destroyed in the landing. But the spacecraft will not operate after it lands because the high gain antenna cannot be pointed at the Earth. Also, the orbiter does no have any means to collect samples from the surface.

Sep 29 2016
3

no. it’s like a fly landing on your arm. it doesn’t change your trajectory. the comet is far more massive than the spacecraft

Sep 29 2016
1

It takes about 5 seconds to transmit a compressed image, so the last picture might be taken only 5 meters above the surface. We’re expecting a best resolution of about 1 centimeter. One problem is that the narrow angle camera cannot focus well at less than one km from the nucleus. The wide angle camera will be in Read more

Sep 29 2016
1

What are the chances that Rosetta’s antennae might point the right way one day and we’d hear from it again?

Sep 29 2016
1

As I said, the landing is at only 1 meter/second. It won’t destroy anything. But we won’t get data after the impact because the high gain antenna will no longer be pointed at the Earth

Sep 29 2016
1

The comet is very massive (as comets go) and millions of times more massive than the spacecraft. The landing should have no detectable effects on the comet’s orbit.

Sep 29 2016
1

Nothing that I’ve heard about.

Sep 29 2016
1

It’s not really a crash. The orbiter will hit at only 1 meter/second, which is walking speed. There’s no enough energy in the impact to create chemical reactions with the surface.

Sep 29 2016
1

I don’t know but the lander is no longer lost. We obtained an excellent picture of it in early September. Check the Rosetta blog for an announcement around September 5.