Wow, I got one right? Cool.

I looked at some of your FAQ’s. With the beryllium added to the copper, it’s the same mix as the Mark 3 reentry body heat shield used on the Poseidon missile.

Also, I love the term “Whipple Shield.” These go back at least to 1951 when he working with von Braun and Ley on their spacecraft concepts for the famous “Colliers” series. He proposed a thin (2 to 3 mm) aluminum shield spaced a few cm off of the surface it was protecting. Any impactor that didn’t just vaporize on the surface would have its energy greatly spread out by having a large number of secondary particles generated, which the lower surface could deal with. This is the basic concept behind segmented armor.

- Jack

We are working on the EPOXI FAQs as well…
http://epoxi.umd.edu/8faqs/index.shtml
Elizabeth
EPOXI webmaster

SPAM ALERT

The comment from Ereksiyon (two or three comments before this one) is SPAM.

You can delete this one too, if you want.

-Dave

Doesn’t whether the Earth gain or lose orbital energy depend on how the flyby goes? I know that at least one astronomer has seriously proposed extending the Earth’s lifetime by using comet bypasses to move it outward over millions of years. Does that mean it would be gaining orbital energy, or losing it? Orbital velocity would be slower, so less kinetic energy, but it would be further from the sun, so more potential energy. Must think about this. I should sit down and do the math. Let me see, can’t do Ep = m g h because solar g isn’t constant over differences of AUs…

I’m not sure, but I can make an educated guess.

Copper is really dense (denser than steel) so you can get a lot of mass without taking up too much room. Also, it can be made very pure (and thanks to the semiconductor industry, it doesn’t even cost too much for that purity). Also too, it’s a material not likely to be found in a comet nucleus, so they can easily subtract the spectral lines for copper from the resulting flash to figure out what the rest of it is.

- Jack

Are you sure you’re not thinking of “Dawn”? I was part of that campaign.

- Jack

I know, I was being sly and incognito.

BTW: I, too, stand in awe of the folks who can coordinate the orbital gymnastics needed to get extra use out of probes like this.

I wonder if any observatories will be having a public visit night

It’ll pass by the Earth tomorrow, on December 31, to steal a bit of our orbital energy as we circle the Sun.

I had to do it…

What million?

Deep Impact 2?

Really man… It’s always baffled me how those folks can even come close to figuring out how to get things like this little gizmo from one place to another using things like orbital influence (or whatever you call it).

I suppose I’m just guilty of watching too many science fiction movies. I want big, honkin’ engines, and a straight line to Hartley 2 in a couple of minutes.

All this little monkeying around with absolutely no margin of error is impressive, and way, way beyond anything I’m capable of doing, but still… Flames! Straight line! Much easier.

And lasers. Just in case Hartley 2 is a little shady.

What? A guy can dream.

BTW, my daughters name is somewhere on that ship. They had an email campaign where people could send in their names and have them added to the spacecraft.