| NASA Center: |
Hubble Space Telescope Center |
|---|
| Image # : |
PR96-13B |
|---|
| Date : |
08/01/1994
|
|---|
|
Title
Cometary Knots Around A Dying Star
Full Description
These gigantic, tadpole-shaped objects are probably the result of a
dying star's last gasps. Dubbed "cometary knots" because their glowing
heads and gossamer tails resemble comets, the gaseous objects probably
were formed during a star's final stages of life. Hubble astronomer C.
Robert O'Dell and graduate student Kerry P. Handron of Rice University
in Houston, Texas discovered thousands of these knots with the Hubble
Space Telescope while exploring the Helix nebula, the closest planetary
nebula to Earth at 450 light-years away in the constellation Aquarius.
Although ground-based telescopes have revealed such objects, astronomers
have never seen so many of them. The most visible knots all lie along
the inner edge of the doomed star's ring, trillions of miles away from
the star's nucleus. Although these gaseous knots appear small, they're
actually huge. Each gaseous head is at least twice the size of our
solar system; each tail stretches for 100 billion miles, about 1,000
times the distance between the Earth and the Sun. Astronomers theorize
that the doomed star spews hot, lower-density gas from its surface,
which collides with cooler, higher-density gas that had been ejected
10,000 years before. The crash fragments the smooth cloud surrounding
the star into smaller, denser finger-like droplets, like dripping paint.
This image was taken in August, 1994 with Hubble's Wide Field Planetary
Camera 2. The red light depicts nitrogen emission ([NII] 6584A); green,
hydrogen (H-alpha, 6563A); and blue, oxygen (5007A).
Keywords
Hubble Space Telescope HST Cometary Knots Helix Nebula Light-Year Constellation Aquarius Wide Field Planetary Camera 2 WFPC
Subject Category
Deep Space Studies, Hubble,
Reference Numbers
- Center:
HSTI
- Center Number:
PR96-13B
- GRIN DataBase Number:
GPN-2000-001370
Source Information
- Creator/Photographer: NASA Robert O Dell Kerry P. Handron Rice University, Houston Texas
- Original Source: DIGITAL
| Resolution | Format | Width
(Pixels) | Height
(Pixels) | Size
(KBytes) |
Thumbnail |
.jpg |
54 |
71 |
10 |
Small |
.jpg |
385 |
504 |
279 |
Medium |
.jpg |
903 |
1181 |
1,165 |
Large |
.jpg |
1805 |
2361 |
3,496 |
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Updated October 31, 2002
• History Questions: NASA History Office
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