Завантаження...

Hs-1999-40-a-full jpg
 

 

 

This photo was viewed 2 times and was downloaded in full size 1 times.

This photo was liked 0 times

Please login in order to see the source link

Summary

Description
English: Hubble Space Telescope's exquisite resolution has allowed astronomers to resolve, for the first time, hot blue stars deep inside an elliptical galaxy. The swarm of nearly 8,000 blue stars resembles a blizzard of snowflakes near the core (lower right) of the neighboring galaxy M32, located 2.5 million light-years away in the constellation Andromeda.

Hubble confirms that the ultraviolet light comes from a population of extremely hot helium-burning stars at a late stage in their lives. Unlike the Sun, which burns hydrogen into helium, these old stars exhausted their central hydrogen long ago, and now burn helium into heavier elements.

The observations, taken in October 1998, were made with the camera mode of the Space Telescope Imaging Spectrograph (STIS) in ultraviolet light. The STIS field of view is only a small portion of the entire galaxy, which is 20 times wider on the sky. For reference, the full moon is 70 times wider than the STIS field-of-view. The bright center of the galaxy was placed on the right side of the image, allowing fainter stars to be seen on the left side of the image.

These results are to be published in the March 1, 2000 issue of The Astrophysical Journal.

Thirty years ago, the first ultraviolet observations of elliptical galaxies showed that they were surprisingly bright when viewed in ultraviolet light. Before those pioneering UV observations, old groups of stars were assumed to be relatively cool and thus extremely faint in the ultraviolet. Over the years since the initial discovery of this unexpected ultraviolet light, indirect evidence has accumulated that it originates in a population of old, but hot, helium-burning stars. Now Hubble provides the first direct visual evidence.

Nearby elliptical galaxies are thought to be relatively simple galaxies comprised of old stars. Because they are among the brightest objects in the Universe, this simplicity makes them useful for tracing the evolution of stars and galaxies.

Object Names: M32, NGC 221

Image Type: Astronomical

Credit: NASA and Thomas M. Brown, Charles W. Bowers, Randy A. Kimble, Allen V. Sweigart (NASA Goddard Space Flight Center) and Henry C. Ferguson (Space Telescope Science Institute).
Date
Source http://hubblesite.org/gallery/album/entire/pr1999040a/
Author NASA and Thomas M. Brown, Charles W. Bowers, Randy A. Kimble, Allen V. Sweigart (NASA Goddard Space Flight Center) and Henry C. Ferguson (Space Telescope Science Institute).

Licensing

Public domain This file is in the public domain because it was created by NASA. NASA copyright policy states that "NASA material is not protected by copyright unless noted". (See Template:PD-USGov, NASA copyright policy page or JPL Image Use Policy.)

Shuttle.svg
Dialog-warning.svg
Warnings:


Licensing:
Public Domain

Comments

Only registered users can post comments. Please login



EXIF data:
File name hs-1999-40-a-full_jpg.jpg
Size, bytes 1282110
Mime type image/jpeg
The images at Free-Photos.biz come mainly from Wikimedia Commons or from our own production. The photos are either in the public domain, or licensed under free linceses: Free-Photos.biz license, GPL, Creative Commons or Free-Art license. Some very few other photos where uploaded to Free-Photos.biz by our users and released into the public domain or into free usage under another free license (like GPL etc.)

All photos in average size can be saved by everyone without registration (by right-clicking) - and all photos can be downloaded in full-size and without the big watermark by members (by left-clicking) (registration and free membership required).

While the copyright and licensing information supplied for each photo is believed to be accurate, Free-Photos.biz does not provide any warranty regarding the copyright status or correctness of licensing terms. If you decide to reuse the images from Free-Photos.biz, you should verify the copyright status of each image just as you would when obtaining images from other sources.


The use of depictions of living or deceased persons may be restricted in some jurisdictions by laws regarding personality rights. Such images are exhibited at Free-Photos.biz as works of art that serve higher artistic interests.

christianity portal