A Snowstorm in Space – Hartley 2 and EPOXI

Following the initial images from the rendezvous of the EPOXI mission with comet Hartley 2, NASA has now released additional images of the extraordinary activity of this comet. A movie of the snow storm can be viewed here. Below left, active vents spew icy particles into space. The diameters range from 3 to 30 centimeters (1 – 12 inches). Below right, closeup of the snow storm swirling around comet Hartley 2. These images are from the left side of the dumbbell shaped comet, as seen from the Deep Impact spacecraft. The right side is much more active, as shown in the press release from Brown University.

Active Vents Spewing Snow from Hartley 2. Image Credit: NASA / JPL–Caltech / UMD / Brown

Close up Image of Basketball sized Particles. Image Credit: NASA / JPL-Caltech / UMD

The color image below shows the different sources for water vapor, dust, carbon dioxide and ice. The images are from data obtained by the High-Resolution Imager on 4 November 2010 on board Deep Impact. Water vapor issues from a source in the middle of the dumbbell, whereas carbon dioxide (and ice and dust) comes predominately from the small end of the comet (right). Dust is released from the active end and from the vents on the middle of the left end, while ice is spewed from various locations.

Infrared Scan of Hartley 2. Image Credit: NASA / JPL-Caltech / UMD

The image below compares the activity of Hartley 2 with the comet Tempel 1, which was the previous target of the Deep Impact spacecraft. This encounter occurred on 4 July 2005, and images of the encounter with the comet and the impactor can be explored on the NASA website. Tempel 1 is 4.7 kilometers on its long axis compared to 2.2 kilometers for Hartley 2. Active jets are clearly visible on Hartley 2, where extensive image processing is required to see them on Tempel 1.

Hartley 2 Activity vs Tempel 1. Image Credit: NASA / JPL-Caltech / UMD

Comet 103P/Hartley 2 – 30 Days from Closest Approach

EPOXI orbit and Rendezvous with Hartley 2 Image Credit: NASA / JPL-Caltech / UMD / GSFC / Tony Farnham

Comet 103P/Hartley 2 on 25 September 2010 Image Credit: Credit: NASA / JPL / UMD

The Deep Impact spacecraft, re-purposed as EPOXI for the encounter with comet Hartley 2, is now 30 days from its rendezvous on 4 November 2010. The image above left shows the orbit of the Earth, EPOXI and comet Hartley 2 leading up to the rendezvous. The image above right is the most recent image of Hartley 2 taken from the Deep Impact spacecraft.

Additional information on the mission can be found here. NASA’s Wide-Field Infrared Survey Explorer spacecraft captured this image of Hartley 2 in May of 2010.

Hartley 2 Imaged by WISE Image credit: NASA/JPL-Caltech/UCLA

Hartley 2 – First Image from Deep Impact

Hartley 2 Seen from Deep Impact Image Credit: NASA / JPL / UM

NASA’s Deep Impact spacecraft, repurposed as EPOXI, has a rendezvous with Comet Hartley 2 on 4 November 2010. From NASA’s press release: EPOXI is an extended mission that utilizes the already “in flight” Deep Impact spacecraft to explore distinct celestial targets of opportunity. The name EPOXI itself is a combination of the names for the two extended mission components: the extrasolar planet observations, called Extrasolar Planet Observations and Characterization (EPOCh), and the flyby of comet Hartley 2, called the Deep Impact Extended Investigation (DIXI). The spacecraft will continue to be referred to as “Deep Impact.”

Comet Hartley 2 – Update

Image Credit: Copyright © 2010 by Bernhard Haeusler (Maidbronn, Germany) The technical details for the animation as given by Bernhard Haeusler are: 20 x 1 min. exposure, 2010-09-02 UT 01:13, 12″ SCT f-5.65 + CCD ST-10XME 12.51 mag (60×60 box), coma: 8′, tail: 1’40” in PA208

Special thanks go to Bernhard Haeusler for the great animation of comet Hartley 2 shown at the left. The animation was released yesterday morning. The comet is currently leaving the constellation of Pegasus and will approach Casseopeia at the end of September. By the beginning of the second week of October, Hartley 2 will be between Cassiopeia and Perseus, and very near M76 (the Little Dumbbell Nebula). Meanwhile, the EPOXI spacecraft is gearing up for the flyby of comet 103 P / Hartley 2. With the closest approach scheduled for 4 November 2010, the spacecraft is beginning its encounter phase. Key observations will include: Spectral maps of gas outbursts as the comet rotates. Infrared maps of the gasses in the inner coma. Search for frozen deposits such as water ice and carbon dioxide on the surface. Determine the size of the nucleus using photographic images. Locate surface features including craters and their distribution and sizes. Map the temperature variations on the surface. Hartley 2 will make its closest approach to Earth this coming 20 October 2010 and its closest approach to the Sun eight days later on 28 October. It should approach magnitude 5 and be visible to the naked eye in dark regions away from cities. For additional information on Hartley 2, see our previous post.

Let us know what you think. What do you want to know about? Post a comment.