Podcaster: Richard Drumm
Title: Space Scoop: Are You Afraid of the Dark?
Organization: 365 Days Of Astronomy
Link : astrosphere.org ; http://unawe.org/kids/unawe1610/
Description: Space scoop, news for children
Bio: Richard Drumm is President of the Charlottesville Astronomical Society and President of 3D – Drumm Digital Design, a video production company with clients such as Kodak, Xerox and GlaxoSmithKline Pharmaceuticals. He was an observer with the UVa Parallax Program at McCormick Observatory in 1981 & 1982. He has found that his greatest passion in life is public outreach astronomy and he pursues it at every opportunity.
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Transcript:
This is 365 Days of Astronomy. Today we bring you a new episode in our Space Scoop series. This show is produced in collaboration with Universe Awareness, a program that strives to inspire every child with our wonderful cosmos.
Today’s story is: Are You Afraid of the Dark?
Almost everyone is afraid of the dark at some point in their life. Creaking floorboards, rustling curtains or random bumps in the night can fill people with terror.
But it’s not the dark itself we find so terrifying, it’s the fear of what is lurking in the dark, the fear of not knowing what’s out there. A fear of the dark is actually an evolutionary advantage; it keeps us on our toes in dangerous situations!
But we all know the boogeyman isn’t real, so are there any real monsters to be afraid of? Well, maybe not on Earth, but there are monsters hiding out in space — they’re called black holes.
Black holes form when a massive star dies. Anything that gets too close to a black hole is pulled into it with such a strong force that it has no chance of escape. The monster will gobble it up! With smaller black holes you can even get “spaghettified” or pulled into a long spaghetti-like stream of atoms and slurped down into the black hole!
Yum!
To make these monsters even more menacing, black holes are basically invisible. Until they start to feed, that is. Then we can see them easily enough!
The false color picture in this episode’s album artwork shows two galaxies. The red galaxy in the center has an enormous, feeding supermassive black hole at its center. This is called an AGN, an active galactic nucleus.
These 2 galaxies are in the northern constellation Lynx, right between Leo Minor and Ursa Major. Johannes Hevelius gave it that name because it was so faint that you’d have to have eyes as sharp as a lynx to see it.
If you look closely, you can see a stream of gas, colored green here, and stars colored white, being sucked from the low mass spiral galaxy into the black hole.
Black holes are messy eaters. As it gobbles up material, it is spraying out hot cosmic gas like Cookie Monster scatters cookie crumbs.
The gas shooting out of the black hole has properties that imply an episodic or on & off behavior to the team of astronomers. The hot gas is heating up the entire galaxy to the point where it is unable to make new stars.
Galaxies start out as star-making machines with a simple recipe: gas + gravity = stars. Here we have a galaxy that has everything it needs to form new stars, but it isn’t. It’s a quiescent galaxy. The star making activity is over.
And now for the first time, we know why. The supermassive black hole is blasting out gas in two broad, conical winds like some giant lawn sprinkler.
The gas it has stolen from its neighbor is being partly eaten and partly blasted outward, never to form stars, and it prevents any other gas in the galaxy from forming stars too!
Hey, Here’s A Cool Fact:
The red galaxy is a new type of galaxy called a “red geyser” galaxy.
They are named after geysers found on Earth, for example in Iceland and Yellowstone National Park in the USA. A geyser is a natural pool of hot water that sometimes erupts, sending boiling hot steam and water gushing into the air in sporadic episodes.
Since this new category of galaxy exhibits the same episodic behavior the astronomers were led to name them red geysers.
Thank you for listening to 365 Days of Astronomy!
End of podcast:
365 Days of Astronomy
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The 365 Days of Astronomy Podcast is produced by Astrosphere New Media. Audio post-production by Richard Drumm. Bandwidth donated by libsyn.com and wizzard media. You may reproduce and distribute this audio for non-commercial purposes. Please consider supporting the podcast with a few dollars (or Euros!). Visit us on the web at 365DaysOfAstronomy.org or email us at info@365DaysOfAstronomy.org. This year we will celebrate more discoveries and stories from the universe. Join us and share your story. Until tomorrow! Goodbye!