5 ms·

Directed Energy Planetary Defense and Relativistic Probes

53 points by chr1 11y ago

executive 11y ago
Naming it DEath-STAR is probably not the best way to build public support.
- defiblep 11y ago
  Have you met geeks? > sufficient warning Well, yes, quite. Wouldn't we be better off making sure we can reliably find them first?
  - privong 11y ago
    > Wouldn't we be better off making sure we can reliably find them first? People are already are working on that. For example, there's the NEOWISE project[0], which used the Wide-field Infrared Survey Explorer to look for potentially dangerous astroids. And there is a ongoing effort for a new space mission, NEOCAM[1], specifically designed to do this same thing and find more objects. [0] http://neo.jpl.nasa.gov/programs/neowise.html http://neo.jpl.nasa.gov/programs/neowise.html [1] https://en.wikipedia.org/wiki/Near-Earth_Object_Camera https://en.wikipedia.org/wiki/Near-Earth_Object_Camera
  - Hobietime 11y ago
    They propose additions use cases for the array in their papers. These include a LIDAR based detection system. I'm on my phone right now so I can't link the appropriate one. Let me know if you are interested and I can find it later.
- lolc 11y ago
  With powerful systems you never know whether they are going to save you or evaporate you. Funny shit like this doesn't get funding unless there are military options to it I'd wager.
brotaku 11y ago
Trying to force asteroids away are we?
jlebrech 11y ago
can this be weaponised to direct asteroids to a particular place on earth? just asking for a friend.
- JulianMorrison 11y ago
  My guess is no. Reason: steering towards is a smaller target than steering away. If you can only point a laser from over here, it's hard to steer an asteroid any way except "thataway" (normal to the most visible surface).
  - viggity 11y ago
    unless the asteroid was closer to the sun than the earth, then you could push it so it hit earth 6 months from when you pushed it.
- ChuckMcM 11y ago
  The available thrust directions are limited given that the laser is presumably in orbit or perhaps at a Lagrange point. Of course once you have a multi-mega (or giga) watt laser in orbit you can pretty much dictate terms to anyone else who wants to use space. After all one person's 'space junk' is another persons 'operating surveillance satellite' :-) I'm a much bigger fan of the idea of using drone space craft with an ion engine which has essentially a gooey blob/harpoon on the front of it, that you attach to/spear the desired object, and then turn on your ion engine to provide enough delta-v to put it where it won't hurt anyone.
- ceejayoz 11y ago
  Probably, but it'd require nation-state level of resources to build and get the system into orbit, plus months/years of lasering. It'd become pretty quickly apparent what you're doing and your satellite would fairly rapidly become an expanding cloud of debris.
fitzwatermellow 11y ago
Happened to catch rockstar astrophysicist Neil deGrasse Tyson on Charlie Rose the other night and the subject of asteroid deflection came up. For small candidates, vaporization would be ideal. But for larger ones, any attempt at destroying them may have unwanted consequences. Debris fields, partial cleaving, etc. Sending a team of human miners with demolition expertise is not in the cards. So the current vogue in asteroid deflection would be to send something heavy to intercept the asteroid and deflect it a degree or two using only gravitational pull! A very clean and elegant solution that would no doubt make a great simulation or video game ;) Mission Concepts and Operations for Asteroid Mitigation Involving Multiple Gravity Tractors http://www.ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20120013195.pdf http://www.ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/201...
- valarauca1 11y ago
  This already exists in a video game. It's call kerbal space program. But instead of gravity you can attach thrusters to asteroids to deflect them. The mod was created by NASA.
  - frandroid 11y ago
    What do you think the smilie was about...
- chr1 11y ago
  A nice thing about this is that it doesn't need to destroy the large asteroid, it just vaporizes small part of it creating thrust and changing the trajectory. One of the videos mentioned bringing asteroids with useful resources closer as a possible usecase.
- mabbo 11y ago
  The point isn't the vaporize them, it's to nudge them ever so slightly. Consider a comet- you fire one or more lasers to a specific spot on the comet, causing heat. The heat causes the water to expand, and shoot off from the comet. Does this destroy the comet? Certainly not much of it. But as that water vapor shoots away from it, Newtons Third Law comes into play and the comet, ever so slightly, is pushed in the opposite direction. You may rightfully say that this would be a very minuscule push, so what good will it do? Well, if you play Kerbal Space Program you'll quickly learn that tiny nudges can have huge effects in the long-run, especially on big orbits. Add a few mm/s to the velocity of a comet two years ahead of time, and it can make the difference between that comet hitting a planet, or not. It can mean the comet is ever so slightly closer to Jupiter, causing it to be pulled by its gravity just a bit more.
JulianMorrison 11y ago
Welp, it's officially the future once we have planetary defense laser bases.
LinuxBender 11y ago
What is our next move when it shoots back?
- simonebrunozzi 11y ago
  LOL!
bakhy 11y ago
has anyone checked out the relativistic probes claim? what potential speeds are we talking about? and, i presume, there are no brakes? :D
Terr_ 11y ago
> DE-STAR or Directed Energy System for Targeting of Asteroids and exploRation Ugh! "exploRation"?

53 points by chr1 11y ago

executive 11y ago

Naming it DEath-STAR is probably not the best way to build public support.

defiblep 11y ago
Have you met geeks? > sufficient warning Well, yes, quite. Wouldn't we be better off making sure we can reliably find them first?
- privong 11y ago
  > Wouldn't we be better off making sure we can reliably find them first? People are already are working on that. For example, there's the NEOWISE project[0], which used the Wide-field Infrared Survey Explorer to look for potentially dangerous astroids. And there is a ongoing effort for a new space mission, NEOCAM[1], specifically designed to do this same thing and find more objects. [0] http://neo.jpl.nasa.gov/programs/neowise.html http://neo.jpl.nasa.gov/programs/neowise.html [1] https://en.wikipedia.org/wiki/Near-Earth_Object_Camera https://en.wikipedia.org/wiki/Near-Earth_Object_Camera
- Hobietime 11y ago
  They propose additions use cases for the array in their papers. These include a LIDAR based detection system. I'm on my phone right now so I can't link the appropriate one. Let me know if you are interested and I can find it later.
lolc 11y ago
With powerful systems you never know whether they are going to save you or evaporate you. Funny shit like this doesn't get funding unless there are military options to it I'd wager.

brotaku 11y ago

Trying to force asteroids away are we?

jlebrech 11y ago

can this be weaponised to direct asteroids to a particular place on earth? just asking for a friend.

JulianMorrison 11y ago
My guess is no. Reason: steering towards is a smaller target than steering away. If you can only point a laser from over here, it's hard to steer an asteroid any way except "thataway" (normal to the most visible surface).
- viggity 11y ago
  unless the asteroid was closer to the sun than the earth, then you could push it so it hit earth 6 months from when you pushed it.
ChuckMcM 11y ago
The available thrust directions are limited given that the laser is presumably in orbit or perhaps at a Lagrange point. Of course once you have a multi-mega (or giga) watt laser in orbit you can pretty much dictate terms to anyone else who wants to use space. After all one person's 'space junk' is another persons 'operating surveillance satellite' :-) I'm a much bigger fan of the idea of using drone space craft with an ion engine which has essentially a gooey blob/harpoon on the front of it, that you attach to/spear the desired object, and then turn on your ion engine to provide enough delta-v to put it where it won't hurt anyone.
ceejayoz 11y ago
Probably, but it'd require nation-state level of resources to build and get the system into orbit, plus months/years of lasering. It'd become pretty quickly apparent what you're doing and your satellite would fairly rapidly become an expanding cloud of debris.

fitzwatermellow 11y ago

Happened to catch rockstar astrophysicist Neil deGrasse Tyson on Charlie Rose the other night and the subject of asteroid deflection came up. For small candidates, vaporization would be ideal. But for larger ones, any attempt at destroying them may have unwanted consequences. Debris fields, partial cleaving, etc. Sending a team of human miners with demolition expertise is not in the cards. So the current vogue in asteroid deflection would be to send something heavy to intercept the asteroid and deflect it a degree or two using only gravitational pull! A very clean and elegant solution that would no doubt make a great simulation or video game ;) Mission Concepts and Operations for Asteroid Mitigation Involving Multiple Gravity Tractors http://www.ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20120013195.pdf http://www.ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/201...

valarauca1 11y ago
This already exists in a video game. It's call kerbal space program. But instead of gravity you can attach thrusters to asteroids to deflect them. The mod was created by NASA.
- frandroid 11y ago
  What do you think the smilie was about...
chr1 11y ago
A nice thing about this is that it doesn't need to destroy the large asteroid, it just vaporizes small part of it creating thrust and changing the trajectory. One of the videos mentioned bringing asteroids with useful resources closer as a possible usecase.
mabbo 11y ago
The point isn't the vaporize them, it's to nudge them ever so slightly. Consider a comet- you fire one or more lasers to a specific spot on the comet, causing heat. The heat causes the water to expand, and shoot off from the comet. Does this destroy the comet? Certainly not much of it. But as that water vapor shoots away from it, Newtons Third Law comes into play and the comet, ever so slightly, is pushed in the opposite direction. You may rightfully say that this would be a very minuscule push, so what good will it do? Well, if you play Kerbal Space Program you'll quickly learn that tiny nudges can have huge effects in the long-run, especially on big orbits. Add a few mm/s to the velocity of a comet two years ahead of time, and it can make the difference between that comet hitting a planet, or not. It can mean the comet is ever so slightly closer to Jupiter, causing it to be pulled by its gravity just a bit more.

JulianMorrison 11y ago

Welp, it's officially the future once we have planetary defense laser bases.

LinuxBender 11y ago

What is our next move when it shoots back?

simonebrunozzi 11y ago
LOL!

bakhy 11y ago

has anyone checked out the relativistic probes claim? what potential speeds are we talking about? and, i presume, there are no brakes? :D

Terr_ 11y ago

> DE-STAR or Directed Energy System for Targeting of Asteroids and exploRation Ugh! "exploRation"?