The Extended Region Around the Planetary Nebula NGC 3242

Galex_glx2009-03r_img02_1024

galex_glx2009-03r_img02 April 3rd, 2009

Credit: NASA/JPL-Caltech

This ultraviolet image from NASA's Galaxy Evolution Explorer shows NGC 3242, a planetary nebula frequently referred to as "Jupiter's Ghost."

The unfortunate name of "planetary nebula" for this class of celestial object is a historical legacy credited to William Herschel during the 18th century — a time when telescopes where small and objects like these, at least the central region, looked very similar to gas-giant planets such as Saturn and Jupiter. In fact, NGC 3242 has no relation to Jupiter or any other planet.

Telescopes and their detectors have dramatically improved over the past few centuries. Our understanding of what planetary nebulae truly are has improved accordingly.

When stars with a mass similar to our sun approach the end of their lives by exhausting supplies of hydrogen and helium fuel in their cores, they swell up into cool red-giant stars. In a last gasp before death, they expel the layers of gas in their outer atmosphere. This exposes the core of the dying star, a dense hot ball of carbon and oxygen called a white dwarf. The white dwarf is so hot that it shines very brightly in the ultraviolet. The ultraviolet light from the white dwarf, in turn, ionizes the gaseous material expelled by the star causing it to glow. A planetary nebula is really the death of a low-mass star.

Although low-mass stars like our sun live for billions of years, planetary nebulae only last for about ten thousand years. As the central white dwarf quickly cools and the ultraviolet light dwindles, the surrounding gas also cools and fades.

In this image of NGC 3242 from the Galaxy Evolution Explorer, the extended region around the planetary nebula is shown in dramatic detail. The small circular white and blue area at the center of the image is the well-known portion of the famous planetary nebula. The precise origin and composition of the extended wispy white features is not known for certain. It is most likely material ejected during the star's red-giant phase before the white dwarf was exposed. However, it may be possible that the extended material is simply interstellar gas that, by coincidence, is located close enough to the white dwarf to be energized by it, and induced to glow with ultraviolet light.

NGC 3242 is located 1,400 to 2,500 light-years away in the constellation Hydra. It was discovered by William Herschel in 1785.

Provider: Galaxy Evolution Explorer

Image Source: /image/galex/glx2009-03r_img02

Curator: Spitzer Space Telescope, Pasadena, CA, USA

Image Use Policy: Public Domain

Download Options

  • Full Size Image (2240 x 2240)

Image Details

Image Type
Observation
Object Name
Jupiter's Ghost NGC 3242
Subject - Milky Way
Nebula > Type > Planetary

Distance

Universescale1
4,800 light years
Galex_glx2009-03r_img02_128
 

Position Details

Position (ICRS)
RA = 10h 24m 46.1s
DEC = -18° 38’ 24.5”
Orientation
North is up
Field of View
56.0 x 56.0 arcminutes
Constellation
Hydra

Color Mapping

  Telescope Spectral Band Wavelength
Blue GALEX (FUV) Ultraviolet (Far-UV) 150.0 nm
Yellow GALEX (NUV) Ultraviolet (Near-UV) 230.0 nm
Spectrum_base
Blue
Yellow
Galex_glx2009-03r_img02_1280
×
ID
glx2009-03r_img02
Subject Category
B.4.1.3.  
Subject Name
Jupiter's Ghost, NGC 3242
Credits
NASA/JPL-Caltech
Release Date
2009-04-03
Lightyears
4,800
Redshift
4,800
Reference Url
/image/galex/glx2009-03r_img02
Type
Observation
Image Quality
Good
Distance Notes
Facility
GALEX, GALEX
Instrument
FUV, NUV
Color Assignment
Blue, Yellow
Band
Ultraviolet, Ultraviolet
Bandpass
Far-UV, Near-UV
Central Wavelength
150, 230
Start Time
Integration Time
Dataset ID
Notes
Coordinate Frame
ICRS
Equinox
J2000
Reference Value
156.19210107817744, -18.6401494029339
Reference Dimension
2240, 2240
Reference Pixel
1120, 1120
Scale
-4.16666666666667e-04, 4.16666666666667e-04
Rotation
0
Coordinate System Projection:
TAN
Quality
Full
FITS Header
Notes
Creator (Curator)
Spitzer Space Telescope
URL
http://www.spitzer.caltech.edu
Name
Email
Telephone
Address
1200 E. California Blvd.
City
Pasadena
State/Province
CA
Postal Code
91125
Country
USA
Rights
Public Domain
Publisher
Galaxy Evolution Explorer
Publisher ID
galex
Resource ID
Resource URL
/image/galex/glx2009-03r_img02
Related Resources
Metadata Date
2023-02-24T09:20:41Z
Metadata Version
1.2
×

 

Detailed color mapping information coming soon...

×
Universescalefull
4,800 light years

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