Astronomy Picture of the Day -- Asteroids Near Earth

NASA ^ | October 01, 2011 | (see photo credit)

[SunkenCiv]

Explanation: Though the sizes are not to scale, the Sun and planets of the inner solar system are shown in this illustration, where each red dot represents an asteroid. New results from NEOWISE, the infrared asteroid hunting portion of the WISE mission, are shown on the left compared to old population projections of mid-size or larger near-Earth asteroids from surveys at visible wavelengths. And the good news is, NEOWISE observations estimate there are 40 percent fewer near-Earth asteroids that are larger than 100 meters (330 feet), than indicated by visible light searches. Based on infrared imaging, the NEOWISE results are more accurate as well. Heated by the Sun, asteroids of the same size radiate the same amount of infrared light, but can reflect very different amounts of visible sunlight depending on how shiny their surface is, or their surface albedo. That effect can bias surveys based on optical observations. NEOWISE results reduce the estimated number of mid-size near-Earth asteroids from about 35,000 to 19,500, but the majority still remain undiscovered.

[SunkenCiv]

[Credit: NASA, JPL-Caltech, WISE]

[SunkenCiv]

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[SunkenCiv]

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[momtothree]

Let me get this right... each red dot is an asteroid? Okay... is this the point where I go running and screaming?!! LOL!

[left that other site]

Don’t call them “asteroids”.

They are potential retirement homes for The Lyin’ King and his cohorts come January 2013!

You may, however, call them “ASSteroids”.

[<1/1,000,000th%]

Nice post.

[ixtl]

So the conclusion is (a) we get clobbered by an asteroid, (b) fried when our sun goes nova, or (c) swallowed by a black hole.

At least it puts a bad day in perspective.

[CodeToad]

Old Model: We THINK many object could do major damage.
New Model: We are SURE there are objects that can do damage, just half of what we were guessing before.

[Lawgvr1955]

ITEOTWAWKI

[bigheadfred]

NEOWISE results reduce the estimated number of mid-size near-Earth asteroids from about 35,000 to 19,500, but the majority still remain undiscovered.

Okay people. We reduced the number of what we think we were seeing to what we now think we are seeing, but the true number of what we think we should be seeing is actually much MUCH more.

Now you can go running and screaming.

[Verginius Rufus]

OK, which ones are asteroids and which ones are planetoids?

Now that astronomers have created a category called "dwarf planets," does that mean that there are also "dwarf planetoids"? Or are those just meteoroids?

[Renderofveils]

President: Dan, we didn't see this thing coming?

Truman: Well, our object collision budget's about a million dollars a year. That allows us to track about three percent of the sky, and begging your pardon sir, but it's a big-a@% sky.

;)

[PapaNew]

...and one of those puppies has our number on it.

[PapaNew]

Otherwise know as Hemorrhoids.

[TheOldLady]

Thanks, Fred. That certainly cleared things up for me, and it's all down Pat now.   ;-D

[momtothree]

“Now you can go running and screaming”.

Just waiting for the nod of the head! Aaaaaghhhaaaghhhh! LOL!

[SunkenCiv]

Thanks <1/1,000,000th%!

[SunkenCiv]

It’s amazing what gets found when these studies are done for reasons other than politics. :’) Previously a tiny study done in the 1990s showed that the estimates for big rocks in the vicinity was ten times too high, so there’s nothing to worry about, time to shift funding back to our programs. :’)

[SunkenCiv]

;’)

[SunkenCiv]

Many more than one, probably.