Icy Visitor from Beyond

Wise_wise2010-035_500

WISE_WISE2010-035 October 5th, 2010

Credit: NASA/JPL-Caltech/UCLA

This visitor from deep space, seen here by NASA's Wide-field Infrared Survey Explorer, or WISE, is comet Hartley 2 -- the destination for NASA's EPOXI mission.

The comet--known officially as 103P/Hartley--was discovered fairly recently, in 1986, by Malcolm Hartley in Siding Spring, Australia. It probably originated from an icy orbit close to that of Jupiter's, before something knocked it on a path toward the Sun. The comet circles the Sun every 6.46 years -- its upcoming closest approach to the Sun, called perihelion, will take place on Oct. 28, 2011. EPOXI, which utilizes the already "in flight" Deep Impact flyby spacecraft, will reach the comet on Nov. 4.

The WISE observations are helping the EPOXI team gain a more comprehensive picture of the comet's behavior over time. This image, taken on May 10, 2010, provides the most extensive look yet at the comet's dusty trail -- a path of particles, sort of like a trail of crumbs, that the comet leaves during each of its trips through the inner solar-system. The extent of the trail seen in this view, behind the comet, is 1.8 million kilometers, or 1.1 million miles.

WISE's infrared vision also makes it good at studying the range of dust particle sizes in the trail, as well as the comet's tail, seen here as a fuzzy streak to the right of the comet, in line with the trail. Infrared observations are also useful for measuring the comet's nucleus and rotation rate.

Comet Hartley 2 is about 1.2 kilometers in diameter, or .8 miles. It was approximately 2.3 astronomical units away from the Sun when this picture was taken (an astronomical unit is the distance between Earth and the Sun). When EPOXI reaches the comet on Nov. 4, it will be nearly 1.1 astronomical units away from the Sun and only 0.15 astronomical units from Earth.

The fuzzy background in this picture is noise, primarily from dust in our own solar system. Stars cannot be seen because they are subtracted out during the process of averaging multiple WISE pictures together into this one view.

Infrared light of 4.6, 12 and 22 microns is colored blue, green and red, respectively.

Image Source: /image/WISE/WISE2010-035

Curator: Wide-field Infrared Survey Explorer, Berkeley, CA, USA

Image Use Policy: Pulic Domain

Image Details

Image Type
Observation
Object Name
A.2.2.
Subject - Unspecified
Wise_wise2010-035_128
 

Position Details

Position (ICRS)
RA = 21h 8m 28.2s
DEC = -1° 9’ 28.2”
Orientation
North is up
Field of View
45.0 x 45.0 arcminutes
Constellation
Aquarius

Color Mapping

  Telescope Spectral Band Wavelength
Arrow_left_blue WISE Infrared (Near-IR) 3.4 µm
Arrow_left_cyan WISE Infrared (Near-IR) 4.6 µm
Arrow_left_green WISE Infrared (Mid-IR) 12.0 µm
Arrow_left_red WISE Infrared (Mid-IR) 22.0 µm
Spectrum_ir1
Arrow_top_blue
Arrow_top_cyan
Arrow_top_green
Arrow_top_red
Wise_wise2010-035_1280
×
ID
WISE2010-035
Subject Category
Comet 103P/Hartley 2   Comet Hartley 2  
Subject Name
A.2.2.
Credits
NASA/JPL-Caltech/UCLA
Lightyears
Redshift
Reference Url
/image/WISE/WISE2010-035
Type
Observation
Image Quality
Good
Distance Notes
Facility
WISE, WISE, WISE, WISE
Instrument
Color Assignment
Blue, Cyan, Green, Red
Band
Infrared, Infrared, Infrared, Infrared
Bandpass
Near-IR, Near-IR, Mid-IR, Mid-IR
Central Wavelength
3400, 4600, 12000, 22000
Start Time
Integration Time
Dataset ID
Notes
Coordinate Frame
ICRS
Equinox
J2000
Reference Value
317.117519, -1.157829
Reference Dimension
2699, 2699
Reference Pixel
1350, 1350
Scale
-2.77777784504000e-04, 2.77777784504000e-04
Rotation
0
Coordinate System Projection:
SIN
Quality
Position
FITS Header
Notes
Position is approximate; image consists of multiple frames aligned with the comet as it moved through the sky
Creator (Curator)
Wide-field Infrared Survey Explorer
URL
http://wise.astro.ucla.edu
Name
Email
outreach@ssl.berkeley.edu
Telephone
Address
7 Gauss Way
City
Berkeley
State/Province
CA
Postal Code
94720
Country
USA
Rights
Pulic Domain
Publisher
Publisher ID
WISE
Resource ID
Resource URL
/image/WISE/WISE2010-035
Related Resources
Metadata Date
2011-08-05
Metadata Version
1.2
×

Detailed color mapping information coming soon...

 

×

There is no distance meta data in this image.