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119

@Hobbes answered this in a comment. Your final guess Will it collide with enough energy to initiate fusion with the atoms of the hull? is correct. See the first XKCD What-If comic, "Relativistic Baseball" for details. The short answer is your entire spaceship is going to suffer a sudden and gratuitous existence failure due to the fusion reaction. ps -...


87

No, because it is not in Earth orbit First the payload does have a purpose: it is a boilerplate, and those have a purpose, namely to "test various configurations and basic size, load, and handling characteristics of rocket launch vehicles". Second, you are asking... is the car equipped with a propulsion system to change its trajectory in case of ...


66

Oh, I can answer this one. In my structural geology class, we breezed over a few paragraphs on the tectonics of impact craters, but it was in the textbook, and, being space-related, I was intrigued. One note: while most of the papers you'll find are on our own geology, the moon isn't that different compositionally from Earth at all, so I'm assuming the ...


64

Yes, it's space junk: after about 6 hours, the second stage will stop working and there will be no way to change the trajectory of stage and payload. So it's a non-functional satellite, i.e. junk. An object whose course cannot be controlled, and a potential future navigation hazard. It's not in Earth orbit, so it's unlikely to cause a problem here. There is ...


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 '...


43

Footnotes: ${}^1$ That the term "Space Junk" (as used in this answer and which is probably the right answer) has a different generally agreed meaning in spacecraft lingo than just plain "Junk" has been pointed out in this answer as well as in in this comment. No. 1. It is Space Art. It started as visual art (we watched it on YouTube, it was beautiful! (...


35

I answer this question from a purely structural-mechanical point of view, i.e. not considering fusion as discussed in Dan Pichelman's answer. Will it create a football sized hole through the ship in the blink of an eye [...]? That's probably right. The rock hits the structure so fast that no inertial effects have a chance of taking place before the ...


27

Most likely no. Voyager downlink communication (via its radio link to NASA's Deep Space Network (DSN) is not continuous. You can check the contact schedule at this Voyager site. If everything looks fine during one DSN contact period, and then at the next contact period there's no signal at all, there are myriads of possible causes, ranging from failure of ...


25

How? Simple, because they launched into those orbits. Why? Well, first, let me explain what their orbits actually are. IRAS (13777) and GGSE-4 (2828) are both in high-inclination orbits, 70° and 99°, respectively. The latter is slightly retrograde, as is common for sun-synchronous orbits. However, to fully understand in what plane they are orbiting, we ...


21

Probably not. Just to give you an idea, lunar rocks hit the Earth on a somewhat regular basis. The power required to have a rock hit Earth is equivalent to that of making a 450 m crater. This comes from a 30m asteroid, roughly. The Tunguska event was caused by a 60m rock, and had an explosive power equivalent to that of a large nuclear weapon, around 15 MT. ...


20

Let us consider a 10 kg rock with a $0.1\,\mathrm{m}^2$ cross-sectional area. Further let’s assume that we are lucky and the rock passes only through one wall of the spaceship (say $3\,\mathrm{mm}$ of aluminium) $10\,\mathrm{m}$ of air and another wall. The total mass of material in this cylinder is them about $$ 2700 \times 3 \times 10^{-3} \times 0.1 \...


19

It depends. In the industry, the concern with space junk is whether or not certain objects are a navigational hazard. If the Falcon Heavy payload were on a collision course with an active spacecraft, then it would definitely be a navigational hazard, as it has no way to redirect itself. That said, there really isn't a lot to avoid out where it is going. As ...


19

Lagrange points as I understand it are points in space between 2 objects where the gravitational pull between them is effectively equal. A quick check of Wikipedia's Lagrangian point or any article will show that only one of the five Lagrange points are "between (the) two objects". The pulls are not equal, they balance in such a way as to allow for an orbit ...


17

No. Not too unprotected, as you put it. There are several misconceptions that I find common about the JWST, that need to be addressed: JWST primary mirror elements are not made of glass and do not shatter on impact It's primary hexagon mirror elements are made out of Beryllium powder pressed into blocks, that were later cut in half to create two mirror ...


15

If you saw the video of the Shoemaker-Levy collision you will see that although that was a collection of smaller objects, there is very much a collision, rather than a gas engulfing a solid. Once the object gets within Jupiter's Roche limit it will be torn to pieces, so you will have a hail of objects falling in and burning up through the atmosphere. The ...


14

There are lots of variables here. Gun type, wall thickness, type of shielding used. According to this email exchange, handgun bullets can penetrate 1-3 cm of aluminium. It also states that: (in) a M113A2 APC (armored personnel carrier) the aluminum (hull) is about 3/4 inches The first data I've found for the wall thickness of a space station module is ...


13

At this point in time it seems doubtful that we could intercept and deflect an asteroid large enough to justify being deflected. This is simply a matter of momentum, a large asteroid has a great deal of momentum and the puny little spaceships we can presently intercept an asteroid with can impart only very little momentum. The only way we can substantially ...


12

The modules of the ISS are protected by Whipple shields: basically an extra wall outside the main pressure hull. A micrometeorite would puncture this shield and disintegrate, leaving nothing big enough to penetrate the main hull. In this image, the shield is on the right: In a space suit, you don't have as much protection (it'd weigh too much, and be very ...


12

Both questions are really hard to answer. You can only estimate how often this happens. There is no monitoring system, which constantly observes the entire sky. There is an unknown number of asteroids and comets in the solar system. Right now, the rate of newly discovered objects increases exponentially (due to better and better technology). Today's number ...


12

It's actually a rebound effect that occurs with an impact forming a large crater. https://www.lpi.usra.edu/education/explore/shaping_the_planets/impact-cratering/ explains: Central peaks – Peaks formed in the central area of the floor of a large crater. For larger craters (typically a few tens of kilometers in diameter) the excavated crater becomes so ...


12

It might help to compare the crater formation to a drop impact: It seems that rock can behave like a viscous mass if you hit it fast enough.


10

The general idea behind this is as follows. After a certain size of impact, there isn't really much that will increase the devastation. So if you take two rocks, each half the size of the first, and toss it, you will quite likely have 2 large impacts, instead of 1 large impact. If you manage to make all of the pieces small enough, then there would be less ...


10

I would guess no. What makes the extinction level events so dangerous for us isn't the impact or the shockwave. A shockwave on Mars won't do much damage since the atmosphere is very thin anyway, and it's likely that colonists are mostly living underground (using the ground as radiation shielding). What makes the big impact strikes so dangerous on Earth is ...


9

According to Rich Zurek, Mars Exploration Program chief scientist at NASA's Jet Propulsion Laboratory (JPL), Pasadena, CA whose statement was quoted in recent NASA's press release titled NASA Preparing for 2014 Comet Watch at Mars (January 28, 2014): Our plans for using spacecraft at Mars to observe comet Siding Spring will be coordinated with plans for ...


9

Asteroids, Meteorites, and Comets has this to say: Meteorites between the size of a grain of sand and about four inches (10 cm) in diameter create a bright light trail and usually burn up in the atmosphere. Meteorites between about four inches (10 cm) and 3 feet (1 m) may survive the burning of entry to land on the Earth's surface. Meteorites ...


8

The majority of the rocks from Mars appear to have come from a single impact on Mars, which formed Mojave Crater. I'm finding it difficult to get an exact power for that impact, but the crater is 58 km in diameter. It is a very large crater, one of the type that rarely impacts anywhere. Discovering a Veneran meteorite would be quite rate, as LocalFluff ...


8

To start off, here's an excerpt from Wikipedia on this September 2012 Jupiter impact event: 2012 impact On 10 September 2012 at 11:35 UT amateur astronomer Dan Petersen visually detected a fireball on Jupiter that lasted 1 or 2 seconds using a Meade 12″ LX200. George Hall had been recording Jupiter with a webcam on his 12" Meade; upon hearing ...


8

Depending on what you mean by encounter: Close to Jupiter's Gravity Influence If the planet comes into Jupiter's gravity influence the trajectory will be changed significantly. If it no longer has the necessary velocity to escape then it may be captured and become a new moon of Jupiter. On a smaller scale, this is what likely happened around Mars with ...


8

Douglas Adams summed it up perfectly "Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space." So first up, orbit is quite large, any individual orbiting item is fairly small. (ISS is a singular counter example as probably ...


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