One of the very first closeup photos of the center or nucleus of Comet Hartley 2 from the Epoxi Mission flyby earlier this morning. The bright geysers are jets of icy vapor and dust shooting from cracks in the surface. Comet are fluffy, friable objects; heat from the sun causes some of a comet's ice to vaporize. All images credit: NASA/JPL-CalTech/UMD

Even as NASA’s Deep Impact probe flew by Comet Hartley 2 this morning, a new comet was discovered overnight by Japanese amateur astronomers Kaoru Ikeya
and Shigeki Murakami in the constellation Virgo. Located not far from Saturn’s position in the sky, the new object is called C/2010 V1, and at 8th magnitude, bright enough to see in a small telescope. Once an orbit is established, I’ll post a map to help you find it. For intrepid amateurs who’d like to give it go right now, the comet will be approximately two degrees west of Saturn tomorrow morning at the start of dawn.

Around 9 a.m. Central time today, the spacecraft successfully shot through Hartley 2′s coma and photographed the comet’s nucleus. It’s risky business sending a machine into a comet because of the risk of impact from dust and grit flying all over the place. This is particularly true when you consider the spacecraft’s encounter speed of 27,500 miles per hour.

The Deep Impact probe zooms by Comet Hartley 2 in this artist view of today's flyby. Credit: NASA

Shortly before the flyby, Deep Impact was placed in AutoNav or autopilot mode, where its instruments were programmed to focus on the brightest thing in the field of view other than the sun.  Because it takes a radio signal traveling at the speed of light 75 seconds to cross the 23 million mile gulf between Earth and Deep Impact, the spacecraft has to be able to follow Hartley 2 on its own in real time. Sunlit jets of dust and vaporized ice should provide the light needed to for the cameras to stay centered on the target.

All images and data were stored on Deep Impact’s computers and are currently being downloaded to Mission controllers at the Jet Propulsion Lab in Pasadena, California. Hundreds of photos were taken and images should continue to flow all day long. To stay abreast, you can follow the coverage LIVE on the Web. Check out the latest images HERE or see all five closeup photos together in one collage.

Here are a couple more photos of the 1.4 mile-long peanut-shaped nucleus taken during Deep Impact’s closest approach to the comet. Fantastic! Just relish the detail.

Hartley 2 is the fifth comet nucleus visited by a spacecraft. Previous missions included comets Halley, Borrelly, Wild 2 and Tempel 1.

How exciting to peer into the heart of the comet that we've seen all fall long through binoculars right here on Earth. The smooth area between the bouldery ends looks especially interesting - what causes the difference in texture?