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

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Thu, 17 Oct 2013 14:11:27 -0700 (PDT)
Message-ID: <201310172111.r9HLBRaD005780_at_zagami.jpl.nasa.gov>

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)
Received on Thu 17 Oct 2013 05:11:27 PM PDT