Deep Impact

[MackemX]

http://www.nasa.gov/mission_pages/deepimpact/main/index.html

Approximately 24 hours before impact, the flyby spacecraft releases the impactor into the comet's path. The impactor uses control software and thrusters to guide itself towards the nucleus of the comet. Using optical measurements, the impactor's AutoNav software will steer itself to the brightest object in its line of sight, the Sun-facing side of Tempel 1's nucleus.

During its final moments, the impactor will take the closet images of comet's surface ever. The kinetic energy that will be released by the collision is estimated to be the equivalent of nearly 5 tons of TNT. However, this will only change the comet's velocity by about 0.0001 millimeters per second (0.014 inches per hour). The collision will not appreciably modify the orbital path of Tempel 1, which poses no threat to Earth now or in the foreseeable future.

The resulting collision between comet and impactor will likely punch a crater, anywhere from the size of a Sport Utility Vehicle to a football stadium, into the comet's nucleus. Before, during and after impact, the flyby spacecraft wil be observing events from a safe distance, imaging the crater formation and resulting ejecta. The flyby will then turn away to protect itself from possible damage from the ejecta.

anybody seen this?

quite a good shot to hit a pebble in deep space 8). I just watched the animation and it was pretty good

[yoda313]

Hi,

They had real photos already! Its always amazing how they can be so precise so far away.

GO NASA!

Kevin

[ZAPPER]

Cool stuff!

[MackemX]

I guess they were just practising for the real thing when a big one comes our way one day

[AlecWest]

anybody seen this?

Yes. Unfortunately, I don't have NASA TV. But, I captured their webcast of the 57-minute pre-impact briefing, the 3-hour 17-minute main program, and at 11:00 AM today will capture the 1-hour post-impact press conference. Afterward, I'll convert the whole thing to MPEG2 and burn to DVDs for posterity (it'll take 2).

Interesting note on this capture/conversion. Earlier, I'd captured a number of 300kbps WMV streams from Israeli National TV and converted them to MPEG2. At full-screen 1/4D1, they were pixelated and gave a window-blind kind-of fluttering effect on fast movements. The NASA WMV link, for some reason, was inoperative. Not that others had gotten to it before me, either. I was able to lock onto it ... but it produced a black screen with no sound. So, I captured the 149kbps RM stream ... and here's the interesting part.

I've already converted the pre-impact briefing and program over to MPEG2 (3000kbps, just like the INTV webcasts). But, the RM files converted beautifully. They're not without ALL artifacts ... but there was no pixelation or window-blind effect. Further, the full-screen 1/4D1 MPEG2 file was pretty sharp. There was one scene in the main program webcast where a female photographer was moving past the mission control people taking pictures. She was wearing tight white pants ... and the picture was so sharp I could see her "panty lines." Anyhow, I thought it was interesting that a 149kbps RM file converted to 1/4D1 full-screen MPEG2 better than a 300kbps WMV file. Go figure.

[AlecWest]

I guess they were just practising for the real thing when a big one comes our way one day

They mentioned that, while it wasn't part of their mission's purpose, info gained from this experience could and would be used in the unlikely event that we had to blow one out of the sky (one headed for collision with Earth).

[rallynavvie]

My friend is going to school for post-grad astronomy at Tucson and was telling me about this. Don't get too worried about anything hitting the planet. The nice thing about our good space telescope and all the great observatories on the ground is they're constantly identifying masses in space. If there were some object on a collision course we'd know about it perhaps hundreds of years before it would happen. It's pretty amazing that using doppler imaging and other resources they can tell exactly what the path of a moving object is even taking into account the movement of our solar system. He said the idea of something hitting the Earth is pretty much just fodder for Hollywood. He said there is still the possibility of something moving incredibly fast through the universe and just happening to strike us but with how large the universe is the odds are just so slim of something like that happening. And if it does we certainly won't have time to cry about it

[thevoelk]

The idea of something hitting the Earth is Hollywood fodder? What about that big hole off the Yucatan Peninsula? The Earth gets hit everyday with objects from space, most of them burn up in the atmosphere. Looks like your friend has a lot of studying ahead of him.

[BJ_M]

i think they faked it like the moon landings


pretty good to hit a 23,000mph moving target for sure ..

[rallynavvie]

Anything big enough to cause a major disaster is pretty easy to pick up with ground telescopes. We would see it coming probably hundreds of years before it actually hit. And for the conspiracy theorists who think the government would cover it up there are just too many amateurs that use some of the big observatories that it'd be pretty tough to keep it a secret.

[ZAPPER]

Bah Humbug! The planet killers are not the problem. The one that just clips us, is the one that will hurt!

[smearbrick1]

It's not the ones that wipe out the entire planet that I worry about (not that I worry). It's the one that hits that causes the mile high tidal wave that washes up in Cleveland. That would suck!

[AlecWest]

The feat was phenomenal and the media is having a field-day with the news. But, if there is a "last hurrah" to be had comet-wise, it might not be by NASA.

The image above is of the Tempel 1 comet. But, it wasn't taken by the fly-by craft. It was taken by a craft launched by the European Space Agency, long before NASA launched Deep Impact. The ESA's craft, called Rosetta, was launched in March 2004. Like Deep Impact, Rosetta is also a 2 part craft. The difference is that Rosetta has a fly-by craft and a lander ... and in 2014, the lander will make a soft landing on a different comet, anchor itself to the surface, and send back data based on direct inspection. Here are the particulars:

http://www.esa.int/esaSC/120389_index_0_m.html

[Lucifers_Ghost]

This is a great feat for science. To be able to hit a target moving so quickly from so far away is astounding.

Now, if they could just figure out a reliable way to predict weather with some sort of accuracy

[AlecWest]

Now, if they could just figure out a reliable way to predict weather with some sort of accuracy

You made me think of something. If someone is a student of the weather, we call them a "meteorologist." What do you call someone who studies "meteors?"

Actually, I know that one ... you call them a METEORITICIST ... and the science is referred to as meteorics.