Bad Astronomy

3 D House of Comet Nucleus!

Via Emily Lakdawalla at the Planetary Society Blog is this amazing 3D animation of the EPOXI spacecraft’s close approach to the nucleus of comet Hartley 2!

You’ll need red/green glasses to see it in 3D, but if you prefer the folks at EPOXI HQ put together a nice flat version:

Incredible! Also at Emily’s blog is an awesome size comparison of various small solar system bodies like comets Halley and Tempel 1 (which EPOXI took a close look at in 2005 when it was still called Deep Impact). The nucleus of Hartley 2 is actually pretty dinky compared to the other comets, but note how similar in shape it is to Halley and Borrelly. Clearly, two-lobed peanut-shaped nuclei are not rare among comets, and even though we’ve only gotten a close look at a handful of them, I’d even wager they’re downright common! That surprises me, and I am not at all sure I understand why that shape is prevalent.

We see it in asteroids like Hektor and Kleopatra, and those may be due to two small asteroids having a slow collision and sticking together. I’d think that’s unlikely with such small objects as Hartley’s nucleus, but the evidence suggests otherwise. I will be very curious indeed to read some papers on this.

The more we look at the Universe – and the more closely we look – the weirder and more wonderful it gets.

Related posts:

- The depth of space
- 3D Apollo
- More *incredible* Phobos imagery
- Opportunity for anaglyphs