Astronomy Picture of the Day 2-25-03

NASA ^ | 2-25-03 | Robert Nemiroff and Jerry Bonnell

[petuniasevan]

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.

2003 February 25

M42: Wisps of the Orion Nebula
Credit & Copyright: John P. Gleason (Celestial Images)

Explanation: The Great Nebula in Orion, an immense, nearby starbirth region, is probably the most famous of all astronomical nebulas. Here, glowing gas surrounds hot young stars at the edge of an immense interstellar molecular cloud only 1500 light-years away. In the above deep image, faint wisps and sheets of dust and gas are particularly evident. The Great Nebula in Orion can be found with the unaided eye just below and to the left of the easily identifiable belt of three stars in the popular constellation Orion. In addition to housing a bright open cluster of stars known as the Trapezium, the Orion Nebula contains many stellar nurseries. These nurseries contain hydrogen gas, hot young stars, proplyds, and stellar jets spewing material at high speeds. Also known as M42, the Orion Nebula spans about 40 light years and is located in the same spiral arm of our Galaxy as the Sun.

[Sally II]

Thanks for the advice, Ronaldus. When we've tried looking at the stars we just aimed for the brightest lights. I guess that wasn't the best method. We'll give it another try on a clear night. :o)

[Ronaldus Magnus Reagan]

Sally, one last thought for you and your dad to consider.

When you look at Saturn through the telescope, you arn't looking at Saturn as it looks at that moment. You are looking at Saturn as it appeared 90 minutes ago! It takes that long for the light to reach you!

As for stars, many stars are at least hundreds (or thousands or millions) of light years away. If a star is 500 light years away, you are looking at the star as it appeared 500 years ago. It might have already blown up (supernova) in the meantime, yet we can't see it yet!

As for the moon, you're seeing how it looked 1 1/2 seconds ago.

Amazing fact, huh?