Podcaster: Richard Drumm
Title: Space Scoop: Black Holes: 15,000 Space Rocks and Counting
Organization:365 Days Of Astronomy
Link : astrosphere.org ; http://unawe.org/kids/unawe1621/
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: Black Holes: 15,000 Space Rocks and Counting
Every single day, the Earth is bombarded by more than 100 tons of dust and sand grain-sized particles. That’s the same as the weight of 14 elephants.
Once a year, an asteroid the size of a car hits Earth’s atmosphere and burns up as a giant fireball before reaching the ground.
Every 2,000 years, a space rock the size of a blue whale hits Earth. And once every few million years, an object large enough to threaten humanity’s future comes along.
Don’t fear, a number of different methods have been devised to keep Earth safe from these rare cosmic threats.
These range from blowing up the asteroid using nuclear weapons to pulling it off target with the weak gravity of a spacecraft to outright hitting them with an impactor to knock it off its collision course.
But to stand a chance of protecting Earth from a deadly impact, we first need to discover all asteroids that pose a threat.
Scientists around the world have been working hard to do this. The 2 biggest programs are the Catalina Sky Survey in Arizona and the Pan-STARRS Project in Hawaii.
These 2 programs account for 90% of the new rocks that are found.
So far, 15,000 of these so-called ‘Near-Earth Objects’ have been discovered – with many more to go.
Only 3 years ago the count stood at 10,000 so we’re finding lots of new rocks out there! But it’s estimated that there are 150 million asteroids over 100 meters in diameter in the solar system.
We’ve got a long way to go!
Near-Earth objects, or NEOs: “Neos”, are asteroids or comets whose orbits come close to ours, meaning they could hit our planet.
We believe that 90% of the 1 kilometer diameter and larger NEOs have been discovered. But only 10% of the medium-sized NEOs have been located and only 1% of the smallest have been found.
As for myself, I don’t like those odds…
The chance that any of the 15,000 NEOs we’ve discovered will impact the Earth in the next 40 years is very small. However, it’s important to watch them closely to make sure they don’t change course.
To do this, telescopes like our partner LCO, the Las Cumbres Observatory, carry out automatic surveys of the entire sky each night, to make sure you, me and the rest of humanity don’t become cosmic target practice.
Soon we will have constructed the LSST, the Large Synoptic Survey Telescope, and we’ll have a very big eye on the sky that should fill in the gaps in our current knowledge.
It will work in a frequency band from near IR to near UV. The camera detector will have a total of about 3.2 gigapixels. This will be the largest digital camera ever constructed.
It’s being built on Cerro Pachón in Chile and will have an 8.4 meter diameter mirror. It’ll scan the entire sky twice a week except for the areas close to the Sun and Moon.
Full science operations are expected in 2023. The primary mirror, which also serves as the tertiary mirror, has already been cast and is being ground to its final curve.
Hey, Here’s A Cool Fact:
There’s more than space rock hunting that the LSST will do. It’ll be helping us understand dark matter & dark energy and the formation and structure of the Milky Way Galaxy.
But also it’ll find short-lived phenomena, the so-called “transients” that come & go unexpectedly. Examples of transient events are gamma-ray bursts, supernovae and X-ray bursters!
Some things really do go bump in the night!
Thank you for listening to the 365 Days of Astronomy Podcast!
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!