[meteorite-list] Hubble Image: Comet ISON Appears Intact

[Ron Baalke]

http://hubblesite.org/newscenter/archive/releases/2013/42/image/a/

News Release Number: STScI-2013-42

Comet ISON Appears Intact
Hubble Space Telescope
October 17, 2013

[Comet ISON Image]

ABOUT THIS IMAGE:

A new image of the sunward plunging Comet ISON suggests that the comet 
is intact despite some predictions that the fragile icy nucleus might 
disintegrate as the Sun warms it. The comet will pass closest to the Sun 
on November 28.

In this NASA Hubble Space Telescope image taken on October 9, the comet's 
solid nucleus is unresolved because it is so small. If the nucleus broke 
apart then Hubble would have likely seen evidence for multiple fragments.

Moreover, the coma or head surrounding the comet's nucleus is symmetric 
and smooth. This would probably not be the case if clusters of smaller 
fragments were flying along. What's more, a polar jet of dust first seen 
in Hubble images taken in April is no longer visible and may have turned 
off.

This color composite image was assembled using two filters. The comet's 
coma appears cyan, a greenish-blue color due to gas, while the tail is 
reddish due to dust streaming off the nucleus. The tail forms as dust 
particles are pushed away from the nucleus by the pressure of sunlight. 
The comet was inside Mars' orbit and 177 million miles from Earth when 
photographed. Comet ISON is predicted to make its closest approach to 
Earth on December 26, at a distance of 39.9 million miles.

For additional information, contact:

Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
villard at stsci.edu

Zolt Levay
Space Telescope Science Institute, Baltimore, Md.
410-338-4907
levay at stsci.edu

Object Name: Comet ISON

Image Type: Astronomical

Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)