Images by Date
Images by Category
Solar System
Stars
White Dwarfs
Supernovas
Neutron Stars
Black Holes
Milky Way Galaxy
Normal Galaxies
Quasars
Galaxy Clusters
Cosmology/Deep Field
Miscellaneous
Images by Interest
Chandra for Kids
Multiwavelength
Sky Map
Constellations
3D Wall
Photo Blog
Top Rated Images
Image Handouts
Desktops
High Res Prints
Fits Files
Image Tutorials
Photo Album Tutorial
False Color
Cosmic Distance
Look-Back Time
Scale & Distance
Angular Measurement
Images & Processing
AVM/Metadata
Getting Hard Copies
Image Use Policy
Web Shortcuts
Chandra Blog
RSS Feed
Chandra Mobile
Chronicle
Email Newsletter
News & Noteworthy
Image Use Policy
Questions & Answers
Glossary of Terms
Download Guide
Get Adobe Reader
More Information
Normal Stars & Star Clusters
X-ray Astronomy Field Guide
Normal Stars & Star Clusters
Questions and Answers
Normal Stars & Star Clusters
Chandra Images
Normal Stars & Star Clusters
Related Podcasts
A Tour of Flame Nebula
Download Image

More Information

More Images
Chandra 0th Order
Image of HD98800
(Credit: NASA/CXC/RIT/
J.Kastner et al.)


Related Images
RCW 38
RCW 38
(18 December 02)
NGC 1068
NGC 1068
(09 July 2003)
TW Hydrae:
Chandra Adds to Story of the Way We Were


TW Hydrae
Credit: Spectra: NASA/CXC/RIT/J.Kastner et al.; Illustration: NASA/CXC/M.Weiss

An artist's conception shows TW Hydrae (left) and HD 98800A (right), two young star systems that are both members of the TW Hydrae stellar association which formed about 10 million years ago. Chandra observations of their X-ray spectra revealed that, although the stars were both formed in the same region of space at the same time, they produce X-rays by different mechanisms.

The insets show portions of the X-ray spectra for each system. Of particular interest are the peaks labeled r, i, and f. These peaks, due to X-rays from neon atoms that have lost all but two of their ten orbital electrons, are sensitive indicators of the density and temperature in the hot, X-ray emitting gas in the star systems.

The relative sizes of the peaks in TW Hydrae provide strong evidence that the matter is accreting onto the star from a circumstellar disk as shown in the illustration. X-rays are produced as matter is guided by the star's magnetic field onto one or more hot spots on the surface of the star.

In contrast, the spectrum of the binary star system HD 98800A revealed that its brightest star is producing X-rays much as the Sun does, from a hot upper atmosphere or corona. This indicates that any disk around these stars has been greatly diminished or destroyed in ten million years, perhaps by the ongoing formation of planets or by its companion stars.

Fast Facts for TW Hydrae:
Credit  Spectra: NASA/CXC/RIT/J.Kastner et al.; Illustration: NASA/CXC/M.Weiss
Category  Normal Stars & Star Clusters
Coordinates (J2000)  RA11h 01m 52.00s | Dec -34 42' 16.00
Constellation  Hydra
Observation Date  July 18, 2000
Observation Time  13 hours
Obs. ID  5
Instrument  ACIS
Distance Estimate  About 190 light years from Earth
Release Date  May 26, 2003

Fast Facts for HD 98800A:
Credit  Spectra: NASA/CXC/RIT/J.Kastner et al.; Illustration: NASA/CXC/M.Weiss
Category  Normal Stars & Star Clusters
Coordinates (J2000)  RA 11h 22m 05.30s | Dec -24 46' 39.80
Constellation  Crater
Observation Date  March 07, 2003
Observation Time  16.5 hours
Obs. ID  3728
Instrument  ACIS
Distance Estimate  About 160 light years from Earth
Release Date  May 26, 2003