The work by Gilfanov and Bogdan described in the recent Chandra Press release represents a major advance in understanding the origin of Type Ia supernovas. Here, in Q & A format, we give some of the backstory of this important discovery.

Illustration: NASA/CXC/M.Weiss

This composite image of M31 (also known as the Andromeda galaxy) shows X-ray data from NASA's Chandra X-ray Observatory in gold, optical data from the Digitized Sky Survey in light blue and infrared data from the Spitzer Space Telescope in red. The Chandra data covers only the central region of M31 as shown in the inset box for the image.

This composite image of data from three different telescopes shows an ongoing collision between two galaxies, NGC 6872 and IC 4970 (roll your mouse over the image above). X-ray data from NASA's Chandra X-ray Observatory is shown in purple, while Spitzer Space Telescope's infrared data is red and optical data from ESO's Very Large Telescope (VLT) is colored red, green and blue.

In celebration of the International Year of Astronomy 2009, NASA's Great Observatories -- the Hubble Space Telescope, the Spitzer Space Telescope, and the Chandra X-ray Observatory -- have collaborated to produce an unprecedented image of the central region of our Milky Way galaxy.

A dramatic new vista of the center of the Milky Way galaxy from NASA's Chandra X-ray Observatory exposes new levels of the complexity and intrigue in the Galactic center. The mosaic of 88 Chandra pointings represents a freeze-frame of the spectacle of stellar evolution, from bright young stars to black holes, in a crowded, hostile environment dominated by a central, supermassive black hole.

A new study unveils NGC 604, the largest region of star formation in the nearby galaxy M33, in its first deep, high-resolution view in X-rays. This composite image from Chandra X-ray Observatory data (colored blue), combined with optical light data from the Hubble Space Telescope (red and green), shows a divided neighborhood where some 200 hot, young, massive stars reside.

M84: A massive elliptical galaxy about 55 million light years away in the Virgo Cluster. More at http://chandra.harvard.edu/photo/2008/m84/

-Kim Arcand, CXC

Last week, we put out a press release on an elliptical galaxy known as NGC 4649. Using Chandra data, a group of astronomers measured the temperature of the hot gas around the galaxy to come up with an independent way to measure the size of the gigantic black hole at the center. You can read more about the details in the press release.