Questions about asteroids.

[The_Rocketeer]

I have to admit to being fairly inexperienced in the world of Kerbal Asteroids. I've never (yet) bothered with redirection or capture, although I have picked out a nice big one for a future mission. Anyway, I've just finished a uni module topic about Near Earth Objects and impact probabilities, and it got me wondering...

What happens to the asteroids that occasionally hit Kerbin?

I'm not talking about the ones that you crash on purpose or deliberately watch all the way in, but more about the ones that happen to crash to Kearth when nobody's looking. What I'm wondering is, if I'm not looking and Jeb's not looking, does it make a thud? Let me say that with less whimsy... do they actually hit Kerbin? What happens if they do?

Never having watched an asteroid do anything, except float along a trajectory line in the tracking station, I would guess that the on-rails physics either passes them straight through the planet (very boring indeed...) or that they pop out of existence when they encounter the atmosphere due to not being inside the physics bubble of an active craft. Well, ok, I thought, but what about asteroids that collide with Mun or Minmus (which must happen sometimes...)? There's no physics bubble on bodies without an atmosphere, so surely these asteroid must hit the surface?

In which case... are there asteroids, right now, lying around, maybe on Kerbin (under the sea?), more likely on Mun or Minmus, that represent my utter failure to protect Kerbalkind from the dangers of deep space? And if not, can someone PLEASE make a mod that does this? It would be absolutely awesome if it created an impact crater and a dust cloud too, but I'm willing to accept that might be beyond the pale...

I know the first person responding to this will just confirm my doubts, but I would ask that people try to use their imaginations and believe a little bit that these asteroids really are just rolling and bouncing around out there waiting to be found...!

Edited November 25, 2014 by The_Rocketeer

[Laie]

if I'm not looking and Jeb's not looking, does it make a thud?

Technically speaking, asteroids are vessels. Like any vessel, the will be silently deleted when coming too close to a body / to deep in an atmosphere. In other words: the thud is the same as with a spent stage.

[Red Iron Crown]

They work like any other debris, they disappear if they go below 23km on Kerbin and are not in the active physics bubble. Not 100% sure how they're handled on airless bodies but I believe they're deleted if they go below 0 altitude.

It would be awesome if they were able to impact when not within the physics bubble. I don't know of a mod that does this, but one might exist or be in the works. It's a similar problem to recovering spent stages.

Edit: Ninja'd.

[The_Rocketeer]

I knew it...

Is it just me or does this seem like a major missed opportunity for awesomeness? I thought the whole point of NASA coming aboard with the redirection mission is this could actually be a real thing at some point in the next few centuries or millennia. Seems really lame that asteroids hitting Kerbin can't even reach the surface, let alone blow up the KSC, while you're building a Laythe colony or exploring the Farside Crater.

[Streetwind]

Not really. The Asteroid Redirect Mission is not and was never about intercepting asteroids that are on a collision course with Earth. In fact, if there was an asteroid on a near-term collision course, then performing the mission as designed would be way too little, too late to prevent the hit.

It's ostensibly a science mission: to study such an asteroid, to field-test solar electric propulsion for heavy-duty hauling work in the Earth-Moon system, and to field-test the Orion spacecraft. (And in reality it's a contrived prestige project for the Obama administration and an excuse for congress to force NASA to build the SLS, thereby funneling most of NASA's budget into the industry of certain states).

The cooperation between NASA and KSP is one of advertising. Squad can advertise the game with the NASA logo, and NASA gets free publicity for their next big human spaceflight mission.

In order for KSP to simulate asteroid strikes, a complete rewrite of the entire physics engine would be required, something that's way out of scope for any single patch. Also, keep in mind that asteroid strikes are very common. About one in 20 will directly collide with Kerbin - I've even started fresh saves with an asteroid already inside of Kerbin's SOI and five days out from divebombing the planet. It would take the player constant effort to keep these pesky rocks away. And finally: none of the asteroids in KSP are actually of significant enough size to realistically cause heavy damage. Even the E-class rocks are slightly smaller than the Chelyabinsk meteor, which - despite causing a shockwave that made a large number of people injure themselves with broken window glass - didn't even manage to reach the ground before burning up because it just wasn't large enough. Conversely, any rock capable of a truly dangerous impact would be significantly larger than an E-class asteroid and really, really tedious for the player to intercept and redirect. Especially if it happens once every two ingame months while the player is trying to timewarp for 1.5 years until the Jool mission finally arrives...

This really is largely a case of "realism for realism's sake doesn't necessarily make a good game"

Edited November 25, 2014 by Streetwind

[The_Rocketeer]

Not really. The Asteroid Redirect Mission is not and was never about intercepting asteroids that are on a collision course with Earth. In fact, if there was an asteroid on a near-term collision course, then performing the mission as designed would be way too little, too late to prevent the hit.

I don't agree with very much that you've said.

KSP is an opportunity for people - even NASA - to experiment with things that can't be experimented with in real life. Asteroid redirection is very much a part of NASAs ongoing mandate, not only for the Earth's protection but for the scientific data that having their hands on a whole asteroid for study could provide. The last 15 years has been spent cataloguing near Earth objects and working out if there are any (albeit over a certain size) that are likely to hit the Earth within 100 years - a mission that is now expanding to cover more and more objects. KSP might seem like a rather silly sort of 'game', but in fact its a very detailed simulator of (somewhat simplified) orbital mechanics. I have no doubt that it's extremely popular over in Washington at NASA Headquarters - after all, the ARMA series and Full Spectrum Warrior games began life as military training software.

I think you're taking a very cynical view of NASA's relationship with KSP. Personally, I could have enjoyed the game as much without it, but that doesn't mean that it's an arrangement that doesn't make sense or enrich the game experience, or have non-commercial benefits for both organisations and players.

The frequency of strikes could be adjusted in the appropriate config file. If it doesn't currently exist, Squad could certainly add it.

There are a number of ways that asteroid strikes could be implemented that would not require any physics overhaul. The game has a trigger to remove an object from the simulator on a collision, so why shouldn't this trigger be coded to produce other effects?

The Chelyabinsk meteor was travelling relatively slowly and didn't hit the ground (in any harmful sense), having burned through a much deeper atmosphere than Kerbin's. Secondly, Kerbin's radius is less than 1/10th the size of Earth's, so it would stand to reason that 'dangerous' objects would also only be 1/10th of RL radius. Therefore a RL scaled E-class asteroid would be 300m across - that's a seriously dangerous asteroid. The Barringer Crater in Arizona (the place where Thor found Mjolnir) was created by an object around 100m across, and created devastation over tens of kilometers.

I'm not asking out of a pursuit for realism, but a pursuit of "awesome" - although I admit I'd find asteroids a lot more interesting if I thought they actually were dangerous. I certainly don't think there's any way this can be accused of being a 'not fun' idea. If an alarm went off on rare occasions summoning you straight to the tracking station because an impactor had been identified, even that would give me a reason to bother going off to tug the hunk of rock around, or at least tuck a few folded parachutes under it's arm. Honestly, the whole thing only even crossed my mind because I was wondering whether, if I flew around in my plane for long enough, I might come across an enormous boulder.

Edited November 25, 2014 by The_Rocketeer

[Streetwind]

Oh, it's not a cynical view, it's a realistic one. Look into other gaming and media partnerships NASA has entered (there are quite a few!), and check NASA statements on why they're doing it Educational, yes. Publicity, sure. Actual science? No, the physics simulation in KSP is not nearly precise enough to be of any use to NASA besides entertainment (and it was never meant to be, either). This humorous xkcd applies.

On the random asteroid strikes, we'll have to agree to disagree, because it's very much a matter of personal taste. A random warning popping up that I have to drop what I'm doing - what I chose to be doing - in order to go do something else because a random number generator decided it's time, that's the very last thing I'd want in my KSP, and I'd instantly turn it off the moment it was patched in. Okay, if it was a one-time event, maybe. But if I have to repeat it regularly? Heck no.

Perhaps there could be an acceptable middle ground, though:

If the asteroid spawning algorithm was tweaked so that it disallows asteroids with a periapsis of less than, say, 200km, that would remove any and all collisions from the procedural system. Then, add the possibility to rarely generate asteroid redirect mission contracts which spawn their own asteroid, with a guaranteed collision course. You could probably even rig up a notification widget message stating that such a contract has just been generated ("we have detected an incoming asteroid!"). The player could then take up this contract - probably worth ridiculous amounts of reputation - and tackle the challenge in the very limited timeframe given. Or they could not tackle said contract and let the asteroid go on its merry way. What happens when it hits, that's open for interpretation.

If it has a chance to wreck my buildings, though, I'm still going to turn it off (or turn destructible buildings off) because I do not want to be forced to actually fly the mission... or rather, the fifteenth such mission. I quit MMOs because I was put off by daily quest grinds, I certainly won't start doing mandatory monthly contract grinds in KSP!

(I believe asteroid redirect mission contracts have been suggested at least a quadrillion times since the introduction of the contract system, by the way. A very popular recurring topic on the Suggestion Forum. It's likely that with 0.90 we're actually getting them, through integrating Fine Print, but perhaps not in the format described here... time will tell.)

Edited November 25, 2014 by Streetwind

[pincushionman]

While planet-affecting environmental effects are certainly possible with rare large asteroids, the key word is rare. Most real meteorites are small and cause at worst localized damage and we're only aware of them because there are so many people everywhere. On Kerbin, the lack of any civilization or infrastructure outside of KSC means that, in the current version, there's literally nothing to hit.

[The_Rocketeer]

"Actual science" is a very general term, and I don't think your definitions are particularly accurate. Any experiment that tests any theory is science. KSP is a scientific model, albeit (as I already said) a somewhat simplified one. Just because the game release is designed to be a toy for the public, there's no reason that NASA shouldn't be using far more accurate versions of the exact same software to map and model the real solar system. If they're not already, I for one believe that they absolutely should be.

Obviously the likelihood of a strike should be remote - I wouldn't want the thing going off every time I logged in - and obviously you would have a choice about whether or not to take any action even if it did go off. Then again, the game could make it very much in your interests to take action by providing a massive bonus to science or funding for doing so.

But I digress. My thinking originally was that it would be interesting if rocks that hit persisted in the same way that landed crafts do.

It just seems like an oversight, having included asteroids, to not include ANYTHING like meteor effects or surface impacts, or even just have the lumps turn up as surface features that can be 'studied' for science. These are the stuff of Hollywood and KSP is all about the big booms, or how to avoid them. Even if the only consequence of a strike was a change in the hue of the atmosphere for a few days I'd find that pretty cool.

Edited November 25, 2014 by The_Rocketeer

[Red Iron Crown]

Just because the game release is designed to be a toy for the public, there's no reason that NASA shouldn't be using far more accurate versions of the exact same software to map and model the real solar system. If they're not already, they I for one believe that they absolutely should be.

I think it's safe to assume that NASA has far better and more accurate software for that sort of thing. N-body physics, greater precision, that sort of thing.

[The_Rocketeer]

I think we're basically saying the same thing as far as that goes.

[Red Iron Crown]

Would be funny (and sad) if a real life mission fell victim to the Kraken, though.

[Arsonide]

It's likelycertain that with 0.90 we're actually getting them, through integrating Fine Print

Fixed that for you!

[The_Rocketeer]

Would be funny (and sad) if a real life mission fell victim to the Kraken, though.

What do you think happened to Beagle 2?

[sal_vager]

What do you think happened to Beagle 2?

I think it hit the ground really hard.

[The_Rocketeer]

I think it hit the ground really hard.

Well, anyway. This conversation has been a fun diversion today, but I think I've got the answer I asked for.

Thanks for your inputs!

[LethalDose]

If anything, I think the ARM mission pack shows that even massive asteroids can be deflected from collisions with relatively small energy expenditures in deep space. Avoiding catastrophic collisions is a major goal of the ARM mission for NASA, even if it's a goal that's down the road. We have to learn how to catch and study small asteroids before we can avert major collisions in the same way we had to learn to shoot a man into space before we could land a man on the Moon.

[The_Rocketeer]

If anything, I think the ARM mission pack shows that even massive asteroids can be deflected from collisions with relatively small energy expenditures in deep space. Avoiding catastrophic collisions is a major goal of the ARM mission for NASA, even if it's a goal that's down the road. We have to learn how to catch and study small asteroids before we can avert major collisions in the same way we had to learn to shoot a man into space before we could land a man on the Moon.

Yes indeed. This really is where I was coming from when I brought NASA up.