Hubble's View Of The Universe (Part 2)

Hubble's View Of The Universe (Part 2 of 10)

THE HUBBLE TELESCOPE

Hubble works on the same principle as the first reflecting telescope built in the 1600s by Isaac Newton. Light enters the telescope and strikes a concave primary mirror, which acts like a lens to focus the light. The bigger the mirror, the better the image.

In Hubble, light from the primary mirror is reflected to a smaller secondary mirror in front of the primary mirror, then back through a hole in the primary to instruments clustered behind the focal plane (where the image is in focus).

THE UNIVERSE

Hubble's longest exposures are like a core sample of the universe, recording galaxies at many different distances. This is one of the deepest core samples ever taken. It shows a few nearby stars in our Milky Way galaxy. The rest of the objects are distant galaxies, extending from 1 billion to over 10 billion light-years away.

STARS

Stars live and die over the course of millions to billions of years. It is unusual to see changes in individual stars. To learn more about them, we must piece together snapshots of stars at different life stages — from birth to death.

The birth, life, and rebirth of stars is an ongoing process in the universe. The byproducts of this process include planets and the elements that make life possible.

GALAXIES

Galaxies come in diverse shapes and sizes. NGC 4414 — which is located about 62 million light-years away — is an example of a spiral galaxy. As with most spirals, the central region of NGC 4414 contains primarily older, yellow and red stars. The outer spiral arms are considerably bluer due to ongoing formation of young, blue stars.

The stars form a flat disk that circles the nucleus — a disk we see tilted, so it doesn't appear flat. Spiral galaxies like NGC 4414 display beautiful spiral arms made up of millions of young stars.

http://hubblesite.org/

Part 3
http://www.youtube.com/watch?v=uI7_IyvEXig&v3

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Tags:

• Hubble
• Universe
• Astronomy
• Cosmos
• Stars
• Galaxies

[neburxv]

haunting...

[MartaBtrp]

Very beautiful!