"NASA tracks only about 3% of the sky for predicting Near Earth Object collisions" Is this true?

Question

What are the chances that a huge asteroid will hit our planet in around a month without prior warning and prediction?

Are we sure that we can predict huge asteroid impacts before a year or even a decade?

Are there chances that the remaining 97% of the NEO(about which we don't have any orbital status etc) to hit us "now, right now" without warning.

Answer 1

The NEO searches, such as LINEAR,  are associated with NASA, but also the Air Force and MIT.  While the search concentrates near the ecliptic, the area covered is more than 6 degrees.  The FAQ does not say, however.  The current camera has a 2 degree field of view.  So each image covers a pretty big chunk of the sky.

From the LINEAR FAQ: The goal is locating at least 90 percent of the estimated 1,000 asteroids and comets that approach the Earth and are larger than 1 kilometer (about 2/3-mile) in diameter, by the end of the next decade (which i think means the end of next year).  This is pretty old.  The current estimates are a little higher.

There's also the Catalina Sky Survey - associated with NASA.

There is also a southern hemisphere NEO search - B U S C A.  It is not associated with NASA.  However, their results are also reported to the Minor Planet Center, so there is a public database of all this stuff.

And check out the Australian effort.

Finally, the Large Synoptic Sky Survey telescope has started construction.  It will image the entire sky every three days to an absurd 25th magnitude.  This is faint enough to pick up objects 100 meters in size.  While i'm not a Windows fan, this project is funded in part by the Gates Foundation.

Despite the current automated surveys, amateur astronomers still find comets, and it still seems to take about 1200 hours of observing to find one.

Answer 2

The chance for a huge impact is already very low. A once in 30,000 years impact is already enough to destroy a large city, but if it impacts some kilometers away from the next city, the damage is already tolerable.

Without advance warning on the other hand is pretty realistic, even with the best sky searches. A comet for example often gets visible only a few weeks away from passing Earth, because of the very high speeds they gained on their way from the rim of the solar system to the inner system.

But still, the chance for a dangerous impact is very low. A ten km comet for example, would only impact once every 280 million years. It would create a 150 km diameter crater, which you can survive well in 500 km distance.

Most objects which have better chances of impacting on Earth are usually better known already, as we do careful sky searches, not only NASA, but also other observatories.  

Answer 3

The space shuttle showed us how NOT to build a sustainable manned spacecraft; and it wouldn't work anyway as an interplanetary vehicle.  The Russians built a space shuttle, flew it once, saw how dumb it was, and went back to their 30-year-old manned spaceflight technology that they still use today.

The Orion spacecraft is modeled after the only successful interplanetary vehicle the United States has produced, but is not simply a re-build of old technology.  The shape of the Orion obviously alludes to Apollo, but only because both Orion and Apollo spacecraft are the obvious solution to the aerodynamic problem of high-speed re-entry.  Borrowing from the space shuttle, certain portions of Orion will be reusable, but only those parts that make sense to reuse.  Reusable heat shields simply aren't safe or practical.  Cargo-return capacity has almost never been used.  The Orion spacecraft is a better execution of the maxim, "Everything you need and nothing you don't."

And while I'm not a fan of the present administration, the shuttle program effectively ended long before Bush took office when NASA announced it would place no more orders for orbiters.  The Downey principle assembly plant was shut down in 1999.

Answer 4

NASA's function is not to track near earth objects.  I would be seriously surprised if they track any at all to tell you the truth.  But rest assured, there are hundreds -even thousands- of very qualified astronomers all over the world who are watching the skies for any undiscovered objects out there.  

http://www.spaceweather.com/

This site home page go towards the bottom of the home page and you will see many links of groups who track the nearly 1000 known near earth objects out there.  

NASA does have an excellent working relationship with all of the astronomers who discover and track these objects, and if their expertise is ever needed, NASA is there for us.  There is nothing to worry about and the facts that you quote above are not accurate.  

Answer 5

Yes and no.  Most NEO are within the ecliptic plane--that's the 3% of the sky you are talking about.  So they do monitor most of the objects.  And all of the known ones that have orbits that could eventually collide with Earth..  In addition, there is an ongoing project to find and track ones not yet discovered.  

A really large asteroid would be spotted anyway--there's too many telescopes pointed in all directions all over the world for one to slip past unnoticed. Smaller ones--big enough to cause serious damage, but not big enough to detect easily--are a possibility.  NASA should be monitoring for these--and does not. They don't have the funds.  So talk to your senators/congressperson.

Not that there's anything we could do about it. ONce the space shuttle retires (not that it has the capability to do anything, either) the US will no longer have a manned space capability--unless and until the so called "replacement" ever flies. Which is looking less  and less likely--its already 4 years behnd schedule. And isn't able to do anything,, anyway--its nothing but an upgraded 1960s style capsule, not a true spacecraft.  The Bush administration and GOP congress refused to build a successor to the Shuttle.  So America is pretty much out of the manned spaceflight business. I guess the conservatives decided to leave it to the Chinese and Russians--who do have active manned space programs.