Astronomy Picture of the Day 10-05-02

NASA ^ | 10-05-02 | 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 October 5

X-Ray Cygnus A
Credit: A. Wilson & A. Young (UMD), P. Shopbell (Caltech), CXC, NASA
(Inset Credit: NRAO)

Explanation: Amazingly detailed, this false-color x-ray image is centered on the galaxy Cygnus A. Recorded by the orbiting Chandra Observatory, Cygnus A is seen here as a spectacular high energy x-ray source. But it is actually more famous at the low energy end of the electromagnetic spectrum as one of the brightest celestial radio sources. Merely 700 million light-years distant, Cygnus A is the closest powerful radio galaxy and the false-color radio image (inset right) shows remarkable similarity to Chandra's x-ray view. Central in both pictures, the center of Cygnus A shines brightly while emission extends 300,000 light-years to either side along the same axis. Near light speed jets of atomic particles produced by a massive central black hole are believed to cause the emission. In fact, the x-ray image reveals "hot spots" suggestive of the locations where the particle jets are stopped in surrounding cooler, denser gas. The x-ray image also shows that the jets have cleared out a huge cavity in the surrounding gas. Bright swaths of emission within the cavity likely indicate x-ray hot material ... swirling toward the central black hole.

[petuniasevan]

Astronomy Fun Fact:

Cygnus A is a spectacular sight, but it would be a very-difficult-to-impossible place for life to exist. That central black hole is churning up the whole galaxy! The optical wavelengths we think of as light are only a small part of the total. For instance, Cygnus A has been imaged in visible light. It's unremarkable at these wavelengths; if all we knew was the light we can see, we'd miss out on such things as today's APOD. See below for the Palomar Observatory's visible-light image.

Yes, that ugly 2-lobed object in the center of the photo is Cygnus A. What a mess, huh?

[petuniasevan]

[BossyRoofer]

It's amazeing how powerful these blackholes are! Great picture, Good job APOD!

[Lil Boop]

Wow. Those are amazing pictures.

[firewalk]

Thanks! (-:

[Mike Darancette]

That must be a really nasty neighborhood to live in.