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Small BodiesStories, updates, insights, and original analysis from The Planetary Society.
Door 27 in the 2010 advent calendar
Time to open the twenty-seventh door in the advent calendar. Where in the solar system is this flat-floored depression?
Door 15 in the 2010 advent calendar
Time to open the fifteenth door in the advent calendar. Where in the solar system is this cratered world?
Door 13 in the 2010 advent calendar
Time to open the thirteenth door in the advent calendar. Where in the solar system are these parallel gouges?
Boulders and Ponds on 433 Eros
There is really cool geology being explored on large, oddly shaped asteroids. The Near Earth Asteroid Rendezvous (NEAR) mission reached 433 Eros in 2000, and one of the exciting results was the discovery of features called
Asteroids and comets to scale, including Hartley 2
Just in time for today's Deep Impact press briefing, which you can watch on NASA TV in a few minutes: I've updated my montage of all the asteroids and comets that have been visited and photographed to include Hartley 2.
Deep Impact at Hartley 2: Two weeks after the flyby
Today the Deep Impact/EPOXI science team held a press briefing that followed up on their very successful flyby of two weeks ago, a status report on what they can say so far about the science that's coming out of the encounter.
A little more information on the Hayabusa samples from Itokawa
Since I posted an update Monday about JAXA confirming extraterrestrial samples in the Hayabusa sample return capsule, JAXA has posted an English-language version of their press release, which contains a bit more information.
365 Days of Astronomy Podcast: What's in a Science Meeting?
Today the 365 Days of Astronomy podcast aired my contribution, What's in a Science Meeting?, about what scientists do at big meetings like the Division of Planetary Sciences.
JAXA announcement: Itokawa sample return successful!
It's official: in a press release today, JAXA announced that some 1,500 dust grains scraped from the interior of Hayabusa's clean-looking sample return capsule are not of terrestrial origin so must be from Itokawa.
DPS 2010: Centaurs and Trans-Neptunian objects
I attended all day Tuesday of the Division of Planetary Sciences meeting on October 5. The afternoon session on Tuesday was a grab bag about different small objects in the outermost solar system.
In which I finally write up last week's Deep Impact Hartley 2 press briefing
On Thursday, November 4, at 13:50 UTC, Deep Impact flew within 700 kilometers of comet Hartley 2. Hartley 2 is the smallest and most active of the five comets that have been directly by a spacecraft, and the first to be visited within the lifetime of its discoverer.
Eris might be smaller than Pluto after all (but it's still more massive)
Several astronomers pointed their telescope at Eris to watch it pass in front of a background star. Occultations permit precise measurement of the diameters of distant, faint objects, and it turned out that Eris was much smaller than previously thought, so much so that its diameter may turn out to be the same as, or even smaller than, Pluto's.
Hartley 2 compared to other comets, and in motion 3D
I had to catch up with tasks left undone at home today and didn't have time to write up my notes from the Hartley 2 press briefing, for which I apologize. I'll leave you for the weekend with three cool Hartley 2 pictures.
Five close-approach images of Hartley 2 by Deep Impact, with commentary
Here's the five close-approach images of Hartley 2 captured today, November 4, 2010, by the Deep Impact spacecraft, collected into one file. Boy, do these images reward close examination!
Hartley 2's jets
It was a very happy set of scientists, engineers, managers, and administrators who filled the Jet Propulsion Laboratory's Von Karman auditorium this afternoon to do the postgame show on Deep Impact's flyby of Hartley 2.
Animation of the five closest-approach Hartley 2 images
Those of you who follow my blog must have known this was coming: now that I got all five new Deep Impact images of Comet Hartley 2 posted and explained, I had to make an animation. Here they are.
Close approach images of Hartley 2!
What a dramatic and cool photo! An asteroid with two lobes like Borrelly, lumpy and bouldery like Itokawa, with gorgeous active jets, dramatically lit. Well done, Deep Impact team!
Deep Impact movies of outbursts from Hartley 2
Since comet Hartley 2 -- the target of Deep Impact's November 4 flyby -- is near its perihelion, it's no surprise that it's an active comet with lots of outbursts.
Three days until Deep Impact's encounter with Hartley 2
The week is finally here: Deep Impact flies past Hartley 2, the smallest comet yet to be visited by a spacecraft, on Thursday, November 4 at 13:50 UTC.
Arecibo images show Hartley 2 is elongated
Comet Hartley 2, the target for Deep Impact's close flyby (now just six days away!) made its closest approach to Earth on October 20, at a distance of 17.7 million kilometers.