Phew! Asteroid's passing was a cosmic near-miss
This YouTube video shows the asteroid's path.
By Stewart Bishop, Globe Correspondent
Although Harvard University astronomer Timothy Spahr spends his life tracking asteroids and minor planets, it's rare when he gets the chance to see one up close.
On Friday night, Spahr received word that an asteroid was headed our way. Though it received little publicity, the asteroid passed by Earth early Monday. At its closest, the asteroid, named 2009 DD45, came within 45,000 miles of Earth, which is around twice as high as some satellite orbits and about one-fifth of the distance between the moon and Earth.
The cosmic object, which was estimated to be 20 yards to 30 yards across, came closest to Earth near the equator somewhere over the Pacific Ocean.
It was about the same size as the one that burned up over Siberia in 1908, leveling nearly 800 square miles of forest in the infamous "Tunguska Event" event.
"It's pretty unusual to see one this close," said Spahr, director of the minor-planet center at the Harvard-Smithsonian Center for Astrophysics in Cambridge. "If an object of this size were to impact the Earth, it would be equivalent to a small nuclear explosion."
Brian Marden, a senior astronomer at the center, said that many such objects pass this close but go unobserved.
"No one is watching the whole sky all the time," Marden said.
He said that light and celestial objects like the moon can affect astronomers' visibility. "If the moon is full, no one is watching," Marden said.
In October 2008, astronomers for the first time tracked an asteroid from space to its impact, when it burned up over Sudan, a mere six hours after it had been discovered.
Spahr said that while asteroids the size of DD45 would pose a catastrophic risk for the planet, they are not the ones that concern him the most.
"Now if an asteroid that was, say, a kilometer across were to strike the earth, that could result in mass extinction," Spahr said. Fortunately for humanity, such asteroids are usually visible several years in advance.
Of the known asteroids, the next time one of such size will come in such close proximity to Earth is in 2029, when the asteroid known as 99942 Apophis, an 885-square-foot space rock, is expected to come within 20,000 miles of the planet.
Material from the Associated Press was included in this report.


Was anyone able to photograph the asteroid as it passed?
I hope they have a plan to blast that next sucker out of the sky.
I remeber approximately 4years ago, reading about these astronmical events.
I wrote a note to the People publisizing these Earth ending events and stated that we should be spending some of the "NASA Budget" to decipher more ways of preventing these in the future.
Since the fact is it will happen, AGAIN, I urge that the world Governments treat this as a mutual potential world disaster, and work together to prevent it from happening. We have the science and knowledge to prevent a future disaster.
I think we saw it. My husband and I were trying to figure out what an odd bright object was in the sky. Is that possible??
Ms Blue, unlikely that you saw it. It was only 30 yrds across, was on an arc close to the equator, and wasnt glowing because it was beyond the atmosphere. Still, its possible. Suggest you check with other news sites to get an approximate time of the passby and then work out any time zone differences.
OH MY GOD!
Sorry Stacey, That was the Sun.
Wow! Way to dodge that punch! Yeah earth! Stick and move. Stick and Move. We have the Muhammad Ali of planets!
No. You didn't see it as it didn't enter the atmosphere is rather a low light object even though it did brighten due to reflctivity as it neared the planet.
We are all going to be amazed one day as a fireball plumets through the atmosphere and impacts. Given that it is large enough many will die, if even longer we can remind oursleves that the dinosaurs too looked up in wonder jest as they ceased to exist as a species.
You might have seen a passing satellite such a the space station but considering the size and distance of DD45 (slightly larger and many times further than the space station) it is unlikely that you saw it without an unassisted eye.
It was released to the media immediately, dingbat. All such observances are. The fact that you didn't happen to see the news reports is no reason to go all paranoid... There is NO coverup or conspiracy going on.
Now should we be demanding more asteroid watching? Definitely yes. And NASA and ESA are both working on it. But thus far, we haven't started working on ways to intercept asteroids. So agitate about that!
tick.......TIck...........TICK......!!!!!!!
I have been watching a very bright object in the western sky for the past few months. I live in Dorset in the South of England. I am no astro anything but expected the media to make mention of it.
Today I went to my local pub only to hear that the bright star was really an asteroid that was going to pass within 44,000 miles (apparently an amateur's estimate) of Earth. I was also told that there hadbeen a media "blackout" because of fears of causing panic. Are we all talking about the same object?
I was also told that across the USA last night that there were sightings of triangular beams of light , Is this connected?
Re: "I hope they have a plan to blast that next sucker out of the sky."
Great, then instead of one object falling we'll have hundreds.
Even if it were feasible (and I'd find it much more practical to nudge the object out of its trajectory than to blow it to pieces) where would the oxygen source for this mythical explosion be found in the vacuum of space? Will we truck up enough O2 to enable a nuclear blast?
Perhaps a solution would be to mount an expedition to the asteroid with the purpose of placing thrusters on the surface to push it off a collision course but a space flight takes years of planning.
I just hope I have enough time to look up and say, "What the heck is that?" before impact.
Has anyone heard of "Planet X?"
I hope one hits the IRS Building in the middle of the night when nobody is there and it is just big enough to leave a crater where the building stood but no damage to the adjacent properties. Then I would believe it was a Divine Intervention.
Tod you would not need O2 for a nuke to explode... Countries have been testing nukes under the surface of the ocean for years. You would only need O2 to generate fire from the explosion. The shockwave would still happen and that is all we need to push that thing away, or destroy it. Also, sound can't travel in space so the the asteroid would never hear it coming! We could all watch it on TV and have John Madden commentate "You know when that nuke hits, its gonna blow the big space rock outta the way.... here it goes BOOM!"
That aside... it's not a very good idea when you don't know what the asteroid is composed of. Like you said we would have hundreds of tiny objects hurtling towards us. Hopefully the rock would be made of solid iron and at that point all a nuke would do is nudge it out of the way.
The expedition thing is a good idea if the rock is brittle, but like you said it does take years to do. I think we would just have to take our chances with a "Super Nuke" that is way more powerful than any weapon that exists today. It's only purpose would be for planetary defense and it would be designed to destroy or deflect anything that might come our way.
When you have a football field or larger sized object going 50,000 MPH or more towards us I doubt any thruster would be enough.. plus where are you going to get all the fuel to sustain a thrust long enough to do anything.
FreedomFighter's comment is HILARIOUS.
Just a heads up! That is Venus in the western sky.
This just goes to prove that God hasn't given up hope on our planet yet!
I can't believe that no one has blamed Obama's tax package for this event :)
OBAMA RULES AND 1 DAY THE ASTERDOID WILL PAS
Has anyone seen this. It's from www.wwmt.com, channel 3 news:
Report: NASA can't keep up with killer asteroids
Comments 4 | Recommend 0
August 12, 2009 12:49 PM
WASHINGTON (AP) - NASA is charged with seeking out nearly all the asteroids that threaten Earth, but a new federal report says the space agency doesn't have the money to do the job.
Although Congress assigned the space agency this mission four years ago, the National Academy of Sciences says it never gave NASA money to build the necessary telescopes.
Even so, NASA says it's completed about one-third of its assignment with its current telescope system.
Disaster movies like "Armageddon" and near misses in previous years may have scared people and alerted them to a serious issue.
But when it comes to doing something about monitoring the threat, the academy concludes "there has been relatively little effort by the U.S. government."
And, according to the report, the U.S. government is practically the only government doing anything at all.
This blogger might want to review your comment before posting it.
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