g Text Version
Beauty & Self
Books & Music
Food & Wine
Health & Fitness
Hobbies & Crafts
Home & Garden
News & Politics
Religion & Spirituality
Travel & Culture
TV & Movies

Bored? Games!
Take a Quiz
Rate My Photo

Women's Fashion
Small Office/Home Office
Holiday/Seasonal Cooking
Crafts for Kids

All times in EST

Full Schedule
g Astronomy Site

BellaOnline's Astronomy Editor


What Herschel Found in a Dark Cloud

A thousand light years away in the constellation of Aquila the Eagle lies a great dark cloud. This cloud (called a nebula) stretches between the stars for some some 65 light years - that's over sixteen times the diameter of our solar system.

Dust completely conceals the interior of this nebula. At least it did until the end of 2009 when the Herschel Space Observatory was able to penetrate the dust to photograph it for the first time. What astronomers found is a stellar nursery, a place where new stars are forming.

A dark nebula is a good place for star formation. Although the material in a nebula is diffuse, it's there in great quantities. A triggering event of some kind, such as a nearby supernova explosion, can cause the cloud to become unstable and start collapsing under its own gravity. It breaks up into fragments which then continue to collapse, becoming denser as they evolve into stars.

Inside the Eagle's nebula astronomers have found six hundred of these condensed regions that will become stars. After some ten thousand years an embryo star, called a protostar, forms in the center of the condensation, giving out heat and light. When it becomes hot enough to sustain nuclear fusion, it becomes a true star.

The Herschel photograph shows these future stars embedded in dark filaments, but hot young stars are already illuminating the nebula to produce two bright regions.

But how did Herschel see through the dust when other instruments couldn't?

Our eyes can't see through dust and neither can telescopes that detect visible light. However light comes in many wavelengths that are invisible to our eyes, including the longer wavelengths of infrared and submillimeter. These can penetrate dust and also see the cooler part of the universe, such as the star-forming regions, which radiate at these wavelengths.

Earth-based telescopes can't detect this light because our atmosphere absorbs it. However Herschel's sensitive instruments can see the entire spectrum of the far infrared and submillimeter radiation, the first to do so.

Herschel was launched in May 2009 by the European Space Agency (ESA), the largest telescope ever sent into orbit. At 3.5 meters (about eleven and a half feet) the main mirror is 0.9 meter (almost three feet) greater in diameter than that of the Hubble Space Telescope.

The telescope was named for William and Caroline Herschel. They were German-born, but worked in England in the seventeenth and eighteenth centuries. William was the discoverer of the planet Uranus and also of infrared radiation. With the assistance of his sister Caroline, he laid the foundations for modern astronomy. Caroline, who was the first woman to discover a comet, got her brother interested in nebulae. Together they surveyed the sky and cataloged the nebulae of the northern hemisphere.

The Herschel Space Observatory has been studying low-temperature objects to help us understand, amongst other things, how stars and galaxies form and evolve, and the chemistry of nebulae.

On April 29, 2013 the mission ended when the infrared observatory finally exhausted its helium coolant.

Follow Me on Pinterest
Add What+Herschel+Found+in+a+Dark+Cloud to Twitter Add What+Herschel+Found+in+a+Dark+Cloud to Facebook Add What+Herschel+Found+in+a+Dark+Cloud to MySpace Add What+Herschel+Found+in+a+Dark+Cloud to Del.icio.us Digg What+Herschel+Found+in+a+Dark+Cloud Add What+Herschel+Found+in+a+Dark+Cloud to Yahoo My Web Add What+Herschel+Found+in+a+Dark+Cloud to Google Bookmarks Add What+Herschel+Found+in+a+Dark+Cloud to Stumbleupon Add What+Herschel+Found+in+a+Dark+Cloud to Reddit

Caroline Herschel
Herschel Museum of Astronomy
Related Articles
Editor's Picks Articles
Top Ten Articles
Previous Features
Site Map

For FREE email updates, subscribe to the Astronomy Newsletter

Past Issues

Printer Friendly
tell friend
Tell a Friend
Email Editor

Content copyright © 2015 by Mona Evans. All rights reserved.
This content was written by Mona Evans. If you wish to use this content in any manner, you need written permission. Contact Mona Evans for details.


g features
Astronomy ABC - H for Herschel Space Observatory

Enceladus 10 Amazing Facts

Zodiac Constellations - Quiz

Archives | Site Map


Past Issues

Less than Monthly

BellaOnline on Facebook

| About BellaOnline | Privacy Policy | Advertising | Become an Editor |
Website copyright © 2015 Minerva WebWorks LLC. All rights reserved.

BellaOnline Editor