A Hyper-Velocity Impact In the Asteroid Belt?

astroengine writes "Astronomers have spotted something rather odd in the asteroid belt. It looks like a comet, but it's got a circular orbit, similar to an asteroid. Whether it's an asteroid or a comet, it has a long, comet-like tail, suggesting something is being vented into space. Some experts think it could be a very rare comet/asteroid hybrid being heated by the sun, but there's an even more exciting possibility: It could be the first ever observation of two asteroids colliding in the asteroid belt."

Comments

Who was driving?

[Anonymous Coward]

A collision between asteroids? Who wants to bet a woman was driving one of them?

Re:Who was driving?

[Shakrai]

My girlfriend and wife both agree that woman are terrible drivers, hence I do all the driving on any trip.

That's funny, the last time I was with your wife and girlfriend they did all the driving, if ya know what I mean...... ;)

Asteroids boring?

[happy_place]

They don't generally collide!? What about when the Millenium Falcon hid in one? Does that mean the Empire Strikes Back was all made up? Next thing you're going to tell me that there aren't giant space eels living in the bigger rocks. (Places fingers in ears and sings loudly Star Wars theme song)

Re:Asteroids boring?

[Chris Mattern]

Our asteroid belt is boring, with every rock more or less tidally locked to each other.

It's also a lot sparser than a lot of people realize--enormously more empty than any representation you see on film, TV or video games. You could fly through it and never see an asteroid with the naked eye except as a point of light.

Why there's a difference.

[argent]

There's a reason you don't normally see icy bodies in circular orbits in the asteroid belt: they'd be blown clean of the ice within a fairly short period of time, astronomically speaking. that's what the tail consists of, dust embedded in the ice being released as the ice sublimes. Which means that the ice here has to have been exposed fairly recently.

Does it happen

[SnarfQuest]

Does it happen to look like a Big Boy statue? Maybe it's Dr. Evil coming back.

We need an asteroid in the face, folks.

[FreakerSFX]

Seriously...not anything big but something Tunguska sized would do, especially over a moderately populated area.

We spend peanuts on detecting potential collisions that could be the cause of the next extinction event. Mark my words, there'll be more money spent on earthquake analysis for Haiti and other "sensational" causes than will be spent on detecting PHOs (potentially hazardous objects) in the next 10 years. I am not denigrating the need to spend money on Haiti - that's a tragedy for sure - but when you look at how reactive we are with public money (New Orleans, anyone? Despite warnings, no one saw this coming?) when a much smaller amount spent up-front would potentially save not just a lot more lives but a lot more money....if better building codes had been in force in Haiti - how many more people would have survived? How much money would have been saved?

I despair for our race. If we saw a dinosaur killer coming and had a program in place already we could probably survive it. Asteroids move slowly but are heavy and require a lot of time/energy to deflect so we would see them early and be able to react...comets move much, much faster but are lighter so presumably if we had the detection gear and a few mass drivers in space already, we could deal with it in a safe time frame.

So give us our Haiti or Katrina from space, please. Make it hurt but not too much - just enough to wake up the people handing out government cash.

Probably not

[Angst Badger]

Everyone knows the asteroids pass right through each other. It's either been shot or it has collided with a ship.

Honestly, what kind of education are scientists getting these days?

Priorities are a function of Probabilities

[Orne]

Scenario 1: Asteroid strike. I defer to NASA JPL, the Tunguska event (100-meter class = ~ 15 mil tons TNT) asteroid occurs once or twice / 1000 years. A 1000-meter class is 1 in 15 million years. An 8000-meter class (dinosaur killer) is 1 in 50-100 million years.

Scenario 2: Earthquake. San Francisco has an annual forecast of earthquake probabilities, and they predict a 68% probability of a 6.7 Magnitude or greater in the next 30 years. Wikipedia gives a probability scale for earthquakes, where a Magnitude 7 (similar to what struke Haiti) occurs 18 / year. A single 6.7 earthquake (P = 120/year) is equivalent to 16 kilotons of energy, or about 1 Tungaska event (P = 0.004/year).

Given the disparity in the probability of asteroid strikes (on populated areas, no less) vs earthquakes, it should be no surprise that the world governments believe money is better spent on earthquake prediction and evacuation relief, not on asteroid strike detection. The "bang for the buck" is clearly higher in earthquake spending.

Re:Priorities are a function of Probabilities

[FreakerSFX]

From an open letter to congress, here:

http://www.spaceref.com/news/viewsr.html?pid=9866

"We cannot rely on statistics alone to protect us from catastrophe; such a strategy is like refusing to buy fire insurance because blazes are infrequent. Our country simply cannot afford to wait for the first modern occurrence of a devastating NEO impact before taking steps to adequately address this threat. We may not have the luxury of a second chance, for time is not necessarily on our side. If we do not act now, and we subsequently learn too late of an impending collision against which we cannot defend, it will not matter who should have moved to prevent the catastrophe . . . only that they failed to do so when they had the opportunity to prevent it. "

We do have the technology. We do have the money. We have a moral obligation to our species to protect it.

Re:Priorities are a function of Probabilities

[syousef]

Given the disparity in the probability of asteroid strikes (on populated areas, no less) vs earthquakes, it should be no surprise that the world governments believe money is better spent on earthquake prediction and evacuation relief, not on asteroid strike detection. The "bang for the buck" is clearly higher in earthquake spending.

1. An earthquake affects a relatively small population.

2. A single dinosaur killer could wipe out humanity.

3. Probability for all these events approaches 1 as time goes on.

In light of the above your "bang for buck" argument is silly. It's like counting the pennies while sitting on the railroad track with your back turned to a huge locomotive with blaring sirens that's about to hit you at 100km/hr and arguing that it costs too much to turn around and look at how close it is, never mind get off your ass and out of the way of the train.

Re:Hyper-Velocity

[camperdave]

Okay. Apparently hypervelocity is an actual astronomy and/or material sciences term:

The term hypervelocity usually refers to a very high velocity, approximately over 3,000 meters per second (6,700 mph, 11,000 km/h, 10,000 ft/s, or Mach 8.8). In particular, it refers to velocities so high that the strength of materials upon impact is very small compared to inertial stresses. Thus, even metals behave like fluids under hypervelocity impact. Extreme hypervelocity results in vaporization of the impactor and target.

Re:Hyper-Velocity

[Convector]

Only in Newtonian mechanics. However, if the objects' velocities are so fast that they would sum to more than the speed of light, then you need to use relativity. In no reference frame does the velocity of one relative to the other exceed c. I'm afraid I'm too lazy to look up the formula. The shelf with all my physics books on it must be 10 feet away from me (although at 0.8c it's only 6 feet).