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64

I’m going to address this as a general question about using airplanes to stop meteors, rather than the very plot specific way the question is worded. Nope. For one very simple reason: Speed. Meteors are not the slow moving flaming behemoths of Hollywood. In reality they’ll be moving at or above Earth's escape velocity (11km/s) when they hit the atmosphere,...


33

Baseball pitchers can throw a ball at around 100mph. That's really quite impressive, however they train to do this and they have good footing. They're also not throwing the ball very far. Bob is in orbit, he's throwing the ball with a starting speed of about 15,000mph perpendicular to the direction he wants it to go, and being generous, 100mph in the ...


30

If he makes a giant potato-gun / slingshot / mini-rocket. Or(!)... Our good old friend Sir Isaac is a right honorable jerk troublesome fellow in these circumstances. According to his first law, in order to de-orbit something, you need to decrease your speed in orbit (*). You need a change (normally denominated delta, $\Delta$) of velocity ($v$) of at least ...


30

Not possible because meteorites move with 11 to 72 km/s. The best chemical explosive octanitrocubane create shockwaves with 10 km/s. This means if the shockwave of the entering meteorite is not powerful enough to disintegrate it (as it often happens), chemical explosives can't do it. When the hit would trigger the explosives immediately (which it cannot), ...


24

Cover it with carbon black then approach from the sun-ward side This is something of the current nightmare scenario for real life planetary scientists. An object covered in carbon black between the star and an observer is incredibly hard to see against the black background of space since the IR radiation from the star is radiated back towards the star ...


21

The answer is no. And if you really feel like it, you can ignore the explosives entirely. In physics, we can always choose our frame of reference to simplify the problem. Let's take our frame of reference to be that of the meteor. If it is traveling at 6km/s with respect to the earth (a conservative estimate made by Joe Bloggs that I like), that means ...


21

You're trying to cure the sickness by alleviating a symptom. You can't cure global warming by putting more pollution into the air. You may temporarily bring the patient's temperature down, but humanity will respond by turning up the heat. In the end, you'll make global warming much, much worse. Please keep in mind that global-warming/climate-change/name-...


15

He fakes it with his dimensional powers To answer your question NO he will not make it in time; and even if he did blow up the meteor the fallout would kill everybody anyway BUT IF the dimensional traveler could just use his powers to take a huge part out of the meteor into another dimension. then blow what’s left up with his plane and make it look like ...


13

If you are close enough to see it visually, and you're not in some kind of bunker, you'll die before the information from your eyes reaches your brain. The infrared and visual light from the impact will cook you instantly. You might actually even die before the impact, the asteroid itself will be heated to such an extreme degree it may cook you as it flies ...


12

Only thing that matters is mass (unless your tech actually increases mass, in other words creates matter from the rift or whatever). So if the mass of the fleets and the space station wasn't enough to destabilize Moon's orbit, then converting that mass to a black hole will not do it either. Nothing really changed, as far as gravity from a moderate distance ...


10

Paint it black. Have it moving really fast, and have it come in from above or bellow the plane of the solar system. If it was painted black(with a nice thick layer of some some kind of tarlike substance) they probably wouldn't see it coming at all. We just don't watch space that carefully with very many telescopes. If we didn't know where to look we'd ...


10

Let's assume that Bob is in an orbit similar to those that the Space Shuttle was normally operating in. In such an orbit, a 200 ft/s retrograde burn was in some circumstances sufficient to deorbit the Shuttle. Depending on the specific orbit, the required delta-v could be as large as 550 ft/s. In civilized units, this corresponds to 61-168 m/s. The rest of ...


10

None No, we would not be showered by debris, because since the Moon is in orbit around Earth, so would any debris be. No, the Moon's orbit will not be affected by something as small as ʻOumuamua. At an estimated volume of 0.00016 km3, and the Moon having a volume of 21 900 000 000 km3, an impact at even an absurd a speed like 1 000 km/s, would affect the ...


9

When any object comes from space into our atmosphere it undergoes ablation - the intense friction and pressure (from air compression) generates heat and corrodes the object away. That's why the smallest bodies never reach the ground, disintegrating in the upper atmosphere. Larger objects may hit the ground after losing some mass to ablation. Blowing up a ...


8

Surprisingly, this question has been studied somewhat extensively in academia. Chapman and Morrison in 1994 did a comprehensive survey of the impact hazard for differently sized comets and meteors on Earth. They have this to say about an impact winter in discussing what constitutes a global catastrophic impact: A global impact winter will commence when ...


8

It would be much, much worse than anything climate change does to us. Any impact large enough to create a global cooling effect would cause catastrophic damage over a huge area, kill a ton of people outright, and cause unpredictable changes to nearly every climate. It would take an immense amount of effort to steer the asteroid into us, and would only ADD ...


7

The Science Fiction Method Get the whole thing painted with this type of paint. .#start rant It would be practically impossible, but who gives two dimes to practicality when you are into making comets invisible from detection? .#end rant Also it should be a small to medium sized comet. You cannot expect a huge Baptistina sized body to not be identified ...


7

In order for Bob's cobblestones to be visible above Alice's house, he's going to need to brush up on orbital decay, drag and gravity. Or crib off the work of ALE’s “Sky Canvas” project, which I am sort of doing right now. ALE would like to release colored meteorites into the atmosphere for a show. As you can see by the handy info-graphic, some planning has ...


7

A lot of people have already mentioned that Oumuamua impacting the moon would not have a serious impact for us here on earth. We have some reason to believe that humans have witnessed massive lunar impacts before. There's a great story from 1178, about a few monks who believed the world was ending when they saw an explosion "split the moon in two" and caused ...


6

It can be a few days since the asteroid becoming visible to an unaided eye, however, only in the last minutes this will turn into something spectacular. From which distance a 6km asteroid is visible? We have to estimate several factors, such as its albedo and angle of approach to Earth. Using Size and Magnitude calculator and assuming albedo is 0.15 (15% ...


6

Orbit isn't far away. Orbit is closer than a nearby city. Orbit is fast away. Things in orbit are going at a ridiculous speed so that they miss the Earth in the time it would take them to fall to the ground, and instead end up on the other side. The small amount of impulse a throwing arm could give would result in a slightly different orbit, missing the ...


6

According to this lovely page one of the smallest reported meteorites is 340-gm (12 ounces) piece of rock that penetrated roof of a house. It is still quite big, though, about a size of a tennis ball as far as my imagination goes. There is no record as to whether it was lethal or not, but if this thing is capable of going through the roof, there is no doubt ...


6

Consider it from the opposite direction. The goal isn't to detect the fainter meteors (although that's an okay side benefit). The goal is to detect the bright ones from further away, so that you can find them first. Clearly ownership of the meteor('s profits) doesn't belong to the person whose property it lands on. If it did, you wouldn't need to detect ...


5

Hide it in full view — Just make it Fast EnoughTM Make it small and fast. The important thing is the impact energy; a very fast and small enough thing, painted yellow and red with the sign "LOOK AT ME, I'M COMING" is practically as good as invisible. Mandatory reference to Randall Munroe's What If site. (By the way --- in that case I really suspect that ...


5

Using the handy Earth Impact Effects Program Calculator for dense rock asteroids I arrive at a diameter of about 150m. Or a comet of about 100m. Calculation result The actual numbers I use: Distance from impact: 12miles (corresponding to the radius of a circle with 450 sq miles area) Projectile density: 3000kg/m^3 - Dense rock asteroid. Impact velocity ...


5

Capturing an asteroid would consist of several steps... Identify The easiest asteroids to capture are going to be the closest, slowest rocks with the least amount of rotation, so these will be prime candidates. You will also want rocks with relatively soft surfaces for the next step. Capture Capturing a rock is fairly simplistic if you think about it, ...


5

Answering by parts. Would we get showered with debris? It depends on a lot of factors, composition, mass, angle of the impact, etc. But not by something like Oumuamua little guy. Would the Moon's orbit be affected? Not significant change in orbit or rotation unless it's really massive/fast object impact. Anyway the energy necessary to achieve it is more ...


4

The second scenario presents the advantages to need less logistics, and it's more complicated to deflect a heavy asteroid (like, kilometers large) than many small ones. In this case, the climatic disorders caused by the fall of the meteors last severals years. It's an augmentation of the rate of carbon dioxide in the atmosphere, resulting from the large ...


4

That's simple - a black hole with a mass in the 1 sol range or less. Nothing else will do. The mass of the black hole is so great that any mass it absorbs in passing through the Earth will not slow it down. The radius (or at least the event horizon) of a 1-sol black hole is about 3 km, and for a 0.1 sol BH it's about 300 meters. In either case, a naïve ...


4

The Chelyabinsk meteor (2013) was about 20m in diameter, and fits most of your criteria: It exploded high above the earth, and did not impact the ground. We had no idea it was coming. This is because of its size and the fact that it was coming from the direction of the sun, making it more difficult to detect. The meteor did not rain down large chunks. It ...


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