Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

September 5, 1996

Watch Galaxies Form
Credit: S. Pascarell, R. Windhorst and S. Odewahn (Arizona State U.), W. Keel (U. Alabama), HST

Explanation: Snips and snails and puppy dog tails, is that what galaxies were made of? In a report released yesterday and soon to be published in Nature, astronomers have imaged an interesting distant patch of sky with the orbiting Hubble Space Telescope. They found many merging groups of stars and gas which have been dubbed "pre-galactic blobs." A particularly dense bunch of these small blue merging objects are visible in the above picture. This may be a snapshot of galaxies actually being formed! Although peculiar by present standards of galaxies, these blobs may have been normal in the distant past, many billions of years ago. This adds evidence that galaxies formed from the conglomeration of smaller objects instead of the fragmentation of larger objects.

Tomorrow's picture: The Largest Impact Crater

< Archive | Index | Search | Calendar | Glossary | Education | About APOD >

Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (USRA)
NASA Technical Rep.: Jay Norris. Specific rights apply.
A service of: LHEA at NASA/ GSFC
&: Michigan Tech. U.