News Release Archive:

News Release 633 of 1051

January 8, 2002 02:00 PM (EST)

News Release Number: STScI-2002-02

Stellar 'Fireworks Finale' Came First in the Young Universe


Image: Going, Going, Almost Gone

Going, Going, Almost Gone Artist's Concept

Screen-use options: These files are created for viewing on your monitor


These three pictures illustrate how a nearby irregular galaxy brimming with star birth would appear at successively greater distances from Earth.

The picture at lower left shows the galaxy, I Zw 18, as it actually appears in a snapshot taken by the Hubble telescope's Wide Field and Planetary Camera 2. The galaxy resides 30 million light-years away in the constellation Ursa Major. The observation was made in November 1994 and March 1995. The bright dots scattered throughout the image represent clusters of stars.

The pictures in the middle and at upper right simulate how the galaxy would appear if it resided at faraway distances - 300 million light-years and one billion light-years, respectively. The two pictures were created by modifying the original Hubble photo of I Zw 18. The colors in all three pictures were selected to enhance important details in the galaxy.

The pictures illustrate that less of the galaxy is seen at successively greater distances from Earth because the fainter stars are no longer visible. At 300 million light-years away, the brightest stars are represented as the white blob near the galaxy's center. At 3 billion light-years away, the brightest region is a small white dot. This simulation demonstrates that astronomers may be missing most of the starlight from the farthest galaxies because it's too faint to see, even with the most powerful telescopes. The star birth they are detecting is just the "tip of the iceberg."

Object Name: I Zw 18

Image Type: Astronomical/Illustration

Archival Image: D. Hunter (Lowell Observ.) and A. Aloisi (JHU)

Simulated Images: A. Fruchter and Z. Levay (STScI)


The above montage includes these images:

Galaxy I Zwicky 18 Image Type: Astronomical Galaxy I Zwicky 18 Simulation Image Type: Illustration Simulation Artist's Concept Simulation Image Type: Illustration Simulation Artist's Concept

All images from this news release:

To access available information and downloadable versions of images in this news release, click on any of the images below: