SoylentNews is people
SoylentNews
There's no need to freak out yet, however. Lawrence Livermore National Laboratory (LLNL), NASA and the National Nuclear Security Administration are on the case, and they're thinking about wielding a big Hammer.
Hammer stands for "Hypervelocity Asteroid Mitigation Mission for Emergency Response," which is an impressive name all on its own. Hammer's a concept at the moment, but if built, it would be a 30-foot-tall (9 meter), 8.8-ton spacecraft that could act as either an asteroid battering ram or as a delivery vehicle for a nuclear device. Let's call it the "nudge or nuke" option.
Bennu is a beast, according to the national lab. It's 1,664 times as heavy as the Titanic and measures more than five football fields in diameter. If it hit Earth, the impact would unleash 80,000 times the energy of the atomic bomb used on Hiroshima in 1945. It would be devastating.
Hammer is designed to launch using NASA's Delta IV Heavy rocket. Researchers at Lawrence Livermore published a paper in the journal Acta Astronautica in February that evaluates the options for using the spacecraft to successfully encourage Bennu to redirect from Earth.
The researchers say ramming the asteroid to change its course would be ideal, but it would need to be a "gentle nudge" that doesn't cause it to break up. It's a complicated proposition.
The team looked at a variety of scenarios. For example, if Earth started launching Hammer missions just 10 years before impact, "it was determined that it could take between 34 and 53 launches of the Delta IV Heavy rocket, each carrying a single Hammer impactor, to make a Bennu-class asteroid miss the Earth," the lab reported on Thursday.
All of this makes it sound like a gentle nudge might not be the best solution for big asteroids.
(Score: 2) by StupendousMan on Monday March 19 2018, @11:44AM (10 children)
The summary doesn't mention why the asteroid Bennu is getting all the attention. The reason is that Bennu's orbit brings it close to the Earth every six years or so. In 2135 (more than a century from now), there's a chance that the close approach will alter its orbit in one particular way, which might cause a LATER meeting of the two bodies to turn into an impact.
See the details in this article from Space.com, written in 2016:
https://www.space.com/33616-asteroid-bennu-will-not-destroy-earth.html [space.com]
(Score: 1) by anubi on Monday March 19 2018, @11:58AM (9 children)
I get the idea a "close call" with Earth would be a good thing.
What I am getting at if it is nudging closer and closer to Earth each go-around, if the call is close enough, and interacts with OUR gravitational field, the interaction may be enough to throw it really off-course so maybe we never see it again. Like how we "slingshot" our probes by using the gravitational fields of other planets.
Of course, we may now have to re-think how many seconds in a year, as such an encounter may slightly speed up or slow down our course around the sun. Might screw up how many years to a leap year, I suppose. The energy to slingshot the thing has to come from somewhere, and my take on it is that will come from the orbital inertia of the Earth as it goes around the sun... I don't think our rotational inertia - day and night - would be much affected... so that would be seconds in a year, not seconds in a day.
Any orbital mechanics guys out there?
"Prove all things; hold fast that which is good." [KJV: I Thessalonians 5:21]
(Score: 1) by anubi on Monday March 19 2018, @12:06PM
Oh, I forgot to add... although the Earth seems large to us, in the grand scheme of things, we are really really small.... I do not believe hitting us is something to keep awake at night over... My guess is about the same probability that an airplane drops out of the sky and nails YOU, Not anyone else - there are what - 7.5 Billion of us? No. Just you. A whole jetliner - with Your name on it. Coming for you. In your bed.
Sweet dreams.
"Prove all things; hold fast that which is good." [KJV: I Thessalonians 5:21]
(Score: 3, Interesting) by GreatAuntAnesthesia on Monday March 19 2018, @12:12PM (5 children)
Can't see that giving a bit of energy to an asteroid is going to affect the Earth's rotation by any appreciable amount. Bennu might be big, but Earth is waaaaaaaaaaaaaaaaaaaaaaaaaaaaay bigger.
Bennu: 78 000 000 000 kg
Earth : 59 720 000 000 000 000 000 000 00 kg
What happened to that plan to divert asteroids by parking a big mirror next to it?
The mirror reflects and focuses sunlight onto one spot on the asteroid, which heats up and evaporates. The matter released provides a tiny amount of thrust. This thrust can be used (over long periods of time) to steer the asteroid onto a different course.
Whatever method is used to divert it, we should throw it at Mars, with a dedicated orbiter+lander mission a few hours behind it, to study the explosion & aftermath.
(Score: 2) by Nuke on Monday March 19 2018, @01:35PM (1 child)
You know it would save keystrokes to use "tonnes" "Megatonnes" or even olde "tons". Points though for not using "Titanics". Yes, I know TFA by LLNL used both kg and Titanics.
(Score: 2) by GreatAuntAnesthesia on Monday March 19 2018, @02:05PM
I thought spelling it out like that wold better illustrate the difference between the two masses.
(Score: 2) by takyon on Monday March 19 2018, @02:02PM
Asteroids are touted as one way to prevent the Sun from making Earth unliveable in 1 billion years:
https://abcnews.go.com/Technology/story?id=98500&page=1 [go.com]
https://www.newscientist.com/article/dn14983-moving-the-earth-a-planetary-survival-guide/ [newscientist.com]
Might not be necessary, or could be used to bolster the "paint the asteroid white" method:
https://news.mit.edu/2012/deflecting-an-asteroid-with-paintballs-1026 [mit.edu]
http://www.spacedaily.com/reports/Asteroids_Deflected_with_Paint_999.html [spacedaily.com]
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 2) by PartTimeZombie on Tuesday March 20 2018, @12:44AM
We should totally do that! With streaming video from every vantage point we can think of.
(Score: 1) by anubi on Wednesday March 21 2018, @05:56AM
Yup... Its gonna take an atomic clock to measure any deviation. It would be easier to detect weight of elephant with and without fly on back.
"Prove all things; hold fast that which is good." [KJV: I Thessalonians 5:21]
(Score: 3, Interesting) by takyon on Monday March 19 2018, @02:20PM
Asteroids could be used to prevent the aging Sun from heating Earth too much, by slowly changing Earth's orbit:
https://www.newscientist.com/article/dn14983-moving-the-earth-a-planetary-survival-guide/ [newscientist.com]
Otherwise, we should begin to think about how asteroids = money. We could put them into temporary orbit [technologyreview.com] around the Earth or Moon to mine them, or maybe do something crazier like smash them or gently nudge them together to make a big rubble pile. Maybe enough asteroids and tiny KBOs could be collected to make Vesta [wikipedia.org] rounded like Ceres (Vesta's dimensions and mass are greater than Mimas [wikipedia.org], which is the smallest known rounded object).
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 3, Informative) by FatPhil on Monday March 19 2018, @02:54PM
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves