Astronomy Picture of the Day 1-29-03

NASA ^ | 1-29-03 | 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 January 29

Orion's Horsehead Nebula
Credit & Copyight: Loke Kun Tan (StarryScapes)

Explanation: The Horsehead Nebula is one of the most famous nebulae on the sky. It is visible as the dark indentation to the red emission nebula seen above and to the right of center in the above photograph. The bright star on the left is located in the belt of the familiar constellation of Orion. The horse-head feature is dark because it is really an opaque dust cloud which lies in front of the bright red emission nebula. Like clouds in Earth's atmosphere, this cosmic cloud has assumed a recognizable shape by chance. After many thousands of years, the internal motions of the cloud will alter its appearance. The emission nebula's red color is caused by electrons recombining with protons to form hydrogen atoms. Also visible in the picture are blue reflection nebulae, which preferentially reflect the blue light from nearby stars.

[petuniasevan]

Tonight, a special tribute:

I hereby dedicate this APOD posting to the man of the hour - President George W. Bush!

Thank you Mr. President for a fine State of the Union Address.
Thank you for your leadership, patience, humility, empathy, and support!

Thanks for agreeing to be our President.

[petuniasevan]

[RadioAstronomer]

Love that pic! :-)

[WSGilcrest]

God Bless our President!

And, a reminder to all:

---

SHUTTLE REENTRY VISIBLE

Launch Alert reader Rick Baldridge recently passed the word that part
of the upcoming reentry of Space Shuttle Columbia will occur over
northern California before dawn on February 1st.

According to Rick "The shuttle will be re-entering the Earth's
atmosphere over the North Bay Area at 4:48am (22 minutes before
landing) which is well before the start of astronomical twilight,
yielding a spectacular sight to all of central and northern
California, Nevada and points east almost to the Mississippi River
basin where sunlight will begin to interfere.

Many PAS [Penninsula Astronomical Society] members have seen these
re-entries before, and they make a fabulous sight -- easily video
taped and/or photographed."

Since the Shuttle will be at a very high altitude when it passes
over northern California, the reentry may be visible for hundreds of
miles either side of the ground track. This could provide a rare
spectacle for the southern part of California.

---

[petuniasevan]

The Horsehead is a very difficult visual object. Seeing it requires a good 'scope, dark skies, a narrowband filter, and near-perfect seeing (no turbulence).

The location for this most famous dark nebula is in Orion's belt, near the easternmost star Zeta Orionis (Alnitak). The Horsehead's designation is B33.

[foolish-one]

And thank you, petuniasevan, for the picture and the dedication.

[Joan912]

Wow is that beautiful!

[panther33]

Such an awesome picture!

Thank you!

[RightWhale]

The Horsehead is a very difficult visual object.

Took my first scope, a 3" reflector, out to try to spy the Horsehead Nebula. Nothing.

Years later took my homemade 6" reflector out to try to see the Horsehead Nebula. Nothing.

Takes more than that. The Horsehead Nebula is tiny and dim.

Of course that all was back in the old days when it was possible to get a clear, dark sky now and then.

[xJones]

Thanks to you I've become a great fan of the Orion Constellation and now the Horsehead Nebula. Keep those posts and pictures coming.

[sistergoldenhair]

Beautiful. Thanks for your work on APOD.

[Soaring Feather]

The usual fantastic!
Astoundingly beautiful.