53

First off, large life-ending asteroid impacts are very rare as there aren't many of them out there and we've found almost all of them: Looking at the 'continent' and 'global catastrophe' areas of shading on the right, the percentage discovered (blue line and numbers on the right hand vertical scale) is 80+%. This may not sound good, but if you look at the '...


13

There is some indirect evidence that Arecibo's loss has already impacted communication with some of the deep space probes. NASA's official statement on Arecibo says this: NASA’s Goldstone Observatory in California, another planetary radar, recently returned to full operations after successful delivery and testing of a new klystron tube for its high-power ...


9

Well SpaceX doesn't plan it's missions (except for current Mars ambitions and the planned Starlink satellite constellation). SpaceX is the company that others hire to carryout their space objectives. If a government wanted to redirect an asteroid, then sure, they could hire SpaceX to get them and their equipment to the asteroid, but SpaceX wouldn't do it ...


6

Yes! Or more precisely, they're developing plans to detect and prevent it. NASA's Planetary Defense Coordination Office (PDCO) exists to... coordinate planetary defense. This includes: Planning and implementation of measures to deflect or disrupt an object on an impact course with Earth, or to mitigate the effects of an impact that cannot be prevented. ...


6

ARM Option B hardware could be useful in deflecting an asteroid, but probably not by the methods you propose or the current Option B mission profile. First of all: Picking up 50 ton boulders is going to have a minute effect on an asteroid massing 1,000,000 tons. Placing the boulders somewhere else on the asteroid will move the centre of mass (by a tiny ...


6

Assuming that our vaporization is at least as effective as a rocket engine (ISP 500) that gives 2.5m/s delta v Unlikely - the rocket engine uses a shaped engine bell tuned to give the best thrust (put simply) over a several minute burn. Whereas vaporised material from the comet itself would consist mainly of low energy expanding gas and its "exhaust angle" ...


5

There are no scenarios for either of those asteroids hitting the earth on the next approach. Both have been tracked carefully for years, and the closest approach has been calculated at 0.035428 Astronomical units, or 3.2 million miles (5.3 million km), which is 13 times as far away as the moon orbits the earth. That is close astronomically, but it is a very ...


5

No, the range of a magnetic field is too short to be usable. Magnetic field strength is proportional to 1/r3, so a magnetic field is only effective at very short distances (less than 10 meters), and quickly becomes way too effective when the debris is in range. You can only attract other objects using a magnet, you can't repel them. So you have to be very ...


5

A magnetic field is one way for one satellite to exert a force on another, changing the orbits of both. Since satellites are mostly made of aluminium, titanium and carbon fibre based composites, however, it is not a very efficient one, a powerful magnet would be needed to produce a small force. Also, if the "predator" is in a similar orbit to the target, it ...


4

There's no simple answer here. In the simple case (no other encounters before impact) you need to generate no more (and maybe a lot less depending on where it's going to hit) than a bit over 6500 kilometers worth of deflection. Note the absence of time units. Deflection, however will normally be measured in meters per second. Note that this does have ...


4

Has SpaceX thought about landing on an asteroid, and deploying technology that can either redirect or disassemble an incoming asteroid to avoid or lesson the asteroids impact on earth? Except perhaps for extracting volatiles from asteroids for use as fuel or oxidizer for missions to Mars, Elon Musk, the founder and CEO of SpaceX, doesn't see much potential ...


4

I don't have an exact answer but some relevant bits of information: You're looking at how much material is vaporized. That's irrelevant, vaporizing material gets you nothing. To move the comet you need to expel material from the surface. Your thrust is based on mass * final velocity (after climbing the comet's admittedly minuscule gravity well), whether ...


4

The simple fact is that we don't know what the effects of a nuclear blast on a comet would be as it's never been done, and each comet is different. You're thinking of a nuclear explosion next to a comet in terms of a hammer, but it's more like a gentle nudge at best. Whatever thrust ratio you get is likely to be very low, what if only .1% of the energy gets ...


4

The threat posed by such near-Earth objects can be illustrated by the most famous extinction-level asteroid, the one responsible for the Chixclub crater of the Yucatán Peninsula. This bolide, at least 10 km wide, is almost universally credited with the demise of the dinosaurs. Defensive measures against such objects entirely depends upon finding it in time ...


3

What are all the activities related to defending planets against impacts from things like asteroids or comets? Are they only things like "identification", "tracking", and "deflection" or are there others? Mitigation. Suppose the Chelyabinsk meteor had been first observed a month prior to impact, and tracked well enough such ...


3

Gas can act as a brake for moving objects in space, in fact NASA has used the atmosphere of (Planets) as a brake on four different occasions with spacecraft. (edited, correction pointed out in comments). But it's not very practical to create a cloud of gas in space. Gas requires gravity to maintain it's cohesion. In space, a cloud of gas would become very ...


2

Leaving aside the practicalities of modifying an ICBM for intercept this is tricky to estimate since the ideal situation involves reducing the object to chunks under 20 meters or so evenly, and nuclear weapons are not exactly precision sieving tools. A first order approximation would be to look at the crater sizes of various surface and subsurface nuclear ...


2

Another way of estimating the energy transferred to the target? 10E+13 kg of comet v.s. 500 kT Nuke: where 1kg TNT=4.2 MJoule. This looks like a 20 km (13 miles) diameter comet. Looks like 10 times the mass of the K-T event (Dino killer). The energy from the bomb will spread in a sphere and less than half will go towards the comet. Lets try 1/3 or 33%. ...


2

It may be helpful to have a sense of the scales involved to see why gas would be ineffective. A stony asteroid with a roughly spherical shape 50 m across is probably the minimum size that might be worth mounting a mission to deflect (at least arguably, especially once we have greatly expanded into space and such things aren't so hard any more). The estimated ...


1

It is too late now to think about a repair. The instrument platform crashed into the dish at the first day of December.


1

There most definitely is a protocol in place for the verification process and disclosure. Most large institutions have protocols in place for front-line research, data, verification, information, discoveries, alerts, release, etc. Not NASA or an asteroid, but there is a some discussion here for SETI and a "contact" for some context: https://www....


1

The other answers address non-doomsday situations. The worst case scenario I can think of is a large comet from the Oort cloud. Comet Hale-Bopp, for instance, was 40-80 km across. That's much larger than the dinosaur killer. Such a comet would show up with only a couple of years' advance warning, and would be massive enough that deflecting it by a large ...


1

A practical way to deflect large asteroids could be kinetic impact with a smaller asteroid. That smaller asteroid would in turn be deflected to collide with the larger asteroid using either a spacecraft that landed on it and used e.g. ion thrusters, or it could be done via a kinetic impact using a yet smaller asteroid. In the latter case, the accuracy of ...


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