Astronomy Picture of the Day 7-25-02

NASA ^ | 7-25-02 | 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.

2002 July 25

NGC 1569: Heavy Elements from a Small Galaxy
Credit: C.Martin (UCSB / Caltech), et al., CXC, NASA

Explanation: For astronomers, elements other than hydrogen and helium are sometimes considered to be simply "heavy elements". It's understandable really, because even lumped all together heavy elements make up an exceedingly small fraction of the Universe. Still, heavy elements can profoundly influence galaxy and star formation ... not to mention the formation of planets and people. In this tantalizing false-color x-ray image from the orbiting Chandra Observatory, small dwarf galaxy NGC 1569 is surrounded by x-ray emitting clouds of gas thousands of light-years across. The gas has recently been observed to contain significant concentrations of astronomers' heavy elements such as oxygen, silicon, and magnesium, supporting the idea that dwarf galaxies, the most common type of galaxy in the Universe, are largely responsible for heavy elements in intergalactic space. A mere 7 million light-years distant toward the long-necked constellation Camelopardalis, NGC 1569 has undergone a recent burst of star formation and stellar supernova explosions. The furious cosmic activity has heated the expanding gas clouds to temperatures of millions of degrees while enriching them with newly synthesized heavy elements.

[petuniasevan]

Astronomy Fun Fact;

Stars' nuclear fusion reactions convert hydrogen and helium to heavier elements in their cores.
Those elements are locked away forever UNLESS that star is large enough to either lose most of its
outer layers during the red giant stage of its life (see planetary nebulae) OR if the star goes supernova.
That's its fate if it is above a certain mass (the "Chandrasekhar limit").

The Chandra X-Ray Observatory orbiting telescope was named
for the famed astrophysicist Subrahmanyan Chandrasekhar.

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[petuniasevan]

APOD PING!

[petuniasevan]

Sorry I'm so late today. Busy all morning and slept all afternoon. Now I get to go to work in an hour.

ANNOUNCEMENT: I am taking vacation August 11-17. I MAY post APOD on the 11th. After that I won't be near a computer for the duration. If someone here wants to cover for me that week, by all means volunteer. You'll need to be able to change intralinks to valid interlinks so they work off the APOD web page.

[2Trievers]

Anyone remember this?

Thanks for all you do 'tunia and have a great vacation! &;-)

[RightWhale]

The August issue of the Discover magazine has an article that suggests there is an uranium nuclear reactor at the center of the earth. The proponent is J. Marvin Herndon, a geophysicist, and while he has some of the earmarks of a classical crackpot, I heard him interviewed on radio last night, and he has a good grasp of reality. More on this later.

[MeekOneGOP]

Nice pic, thanks. I'll let my FRiends know it wasn't named for Chandra Levy, lol!

[2Trievers]

Never mind Discover Magazine ... we have more important things to worry about ... Businessman offers cave shelter from asteroid. Ya' want to go in "halfsies" on one of these caves? Maybe if we get in on the ground floor, we can get one with a decent view. I'll bring the hors d'oeuvres. &;-)

[2Trievers]

Did you notice something wonderful? RightWhale gets info from Discover Magazine and I get my news from Ananova ... LOL Viva la difference! &;-)

[BradyLS]

Cool! Is that what that is? I thought you were slacking on us a pulling screen captures from old Star Trek episodes! :-D ;-)

[MeekOneGOP]

LOL! I checked out your article link. That's funny. The sky is falling!

[RightWhale]

While they are apparently providing free children, I don't believe I would relish the idea of emerging after the asteroid has destroyed a continent, only to find myself in Wales. Bavaria or New Zealand would be good even if they don't offer free children.