Nasa aims to move Earth

Guardian News and Media ^ | 10 June 2001 | Robin McKie, science editor

[Political Junkie Too]

All you have to do is hurtle a few comets at Earth, and its orbit will be altered.

I hope they hit my neighbor's house. That guy always plays his stereo too loud.

-PJ

[Williams]

If you read the article they are talking about one billion years from now when the sun will expand and fry the earth. They say if Earth can then be moved further out, the planet (us) could survive an additional 6 billion years.

They were NOT talking about global warming.

They also recognized the dangers and difficulties of the move, but at that time the alternative will be Earth destroyed.

[eyedigress]

'The collision of a 100-kilometre diameter object with the Earth at cosmic velocity would sterilise the biosphere most effectively, at least to the level of bacteria,

At least the hunt for ManBearPig would be over.

[Rebel_Ace]

Actually, the underlying physics behind the idea is sound. Let's take another planet as the subject, so people won't get so riled up about it. We'll look at VENUS:

Venus has some serious problems with habitability:

(1) It is WAYYY TOO hot.
(2) It's atmosphere is WAYYY TOO thick.
(3) It "spins" too slowly, and in the "wrong" direction.

However, Venus is said to be "Earth's twin" because it is a close match for SIZE and MASS. This means that Venus can offer a human visitor the ONE THING we cannot fake or bring with us on a trip there: EARTH LIKE GRAVITY, vital for normal health and well being.

So, we need to "cool" Venus down, and "spin her up". We can kill both birds with ONE BIG STONE, thrown repeatedly in her direction. By altering the course of a fairly massive asteroid, we can gently "tug" Venus into a cooler orbit, and at the same time gently increase the rate of her spin to match a 24 hour day. Once we get the temps down somewhat, we could introduce aerosol like bacteria to begin breaking down and re-aranging the components of her atmosphere. After about 5000 years of tugging and spinning and bacterial outgassing, WE WOULD HAVE A REAL EARTH TWIN.

Now, imagine humanity with a whole 'nother Earth to live on. Twice the land, twice the resources, and double the chances for our species to live through an astronomical disaster.

Downsides to this plan:
(1) It would cost a lot of money to divert an asteroid
(2) It would take 1000's of years to get to a finished product
(3) If you screw up the calculations or implementations of moving the asteroid, you run the risk of a catestrophic collision

Upsides:
(1) If you are clever about the initial nudging and orbital looping of the asteriod, once you set it into motion, it should largely do all the work on its own, automatically, while we monitor the progress from Earth using telescopes.
(2) We get a whole 'nother planet to play on!

[LonePalm]

I don't think these people understand the gravity of the subject.

This is a stupid idea for very many reasons but I doubt they intend to actually hit the earth. We can talk about unintended consequences later.

What they are talking about is a problem in celestial mechanics. Consider the following picture:

What they want to do is pass objects close in front of the earth in its orbital path so that the gravitational attraction of the object speeds up the earth. If the earth speeds up, it will move to a wider orbit around the sun.

The two biggest of many problems with this are:
1. How do they find and maneuver large comets, many of which are outside the orbit of Neptune? They will have to find several earth masses worth of comets to accomplish even a few meters per second of increased orbital velocity. This might move the earth one earth diameter farther out. I haven't had time to do the math.
2. How do they direct these comets with incredible precision to accomplish the gravitational tug without hitting the earth?

There would be one side benefit of this program. We would see some spectacular meteor showers from the dust trails of the comets for centuries to come.

A bigger problem would be that this plan would perturb the orbit of the moon. It would NOT strip it away as stated in the article. The moon does not orbit the earth. The earth and the moon orbit a common point about 2/3 of the way from the center of the earth to the surface. You can't do just one thing when you play around with gravity. Any comet passing near the earth affects both the earth and the moon.

Garde la Foi, mes amis! Nous nous sommes les sauveurs de la République! Maintenant et Toujours!
(Keep the Faith, my friends! We are the saviors of the Republic! Now and Forever!)
LonePalm, le Républicain du verre cassé (The Broken Glass Republican)

[rjsimmon]

William,

I have read the article, that is why I posted it.

The crux of the argument was the arrogance of the scientific community believing they can control something on a planetary scale, specifically where it involves orbital mechanics. The math is simple enough, but the devil is in the details:

• Find a comet/asteroid of correct size and velocity
• Launch a mission (manned or unmanned) to deliver a propulsion payload to said comet/asteroid
• Successfully deploy said propulsion system
• Initiate previously mentioned propulsion system
• Ensure aforementioned comet/asteroid stays on required trajectory, completes near-Earth sweep, successfully enters new trajectory to Jupiter/Saturn
• Rinse
• Repeat

Remember, these are the same 'scientists' that buried a Martian probe a couple of hundred feet into the Martian soil because someone neglected to convert Miles to Kilometers.

The 'global warming' piece is the ultimate singing of Earth by Sol when she decides to grow up. I have heard that yellow stars do that, eventually becoming red giants...

[rjsimmon]

A couple of small nits to pick:

1-The atmospheric pressure on Venus is 91 times that of Earth. An atmospheric probe that was sent was crushed.

2-No moon (tidal necessity)

3-Exceptionally weak magnetic field

[Star Traveler]

Ummm... that’s a really crazy idea... :-)

[Rebel_Ace]

Well, no plan is perfect ;-)

About your "nits":

1-The atmospheric pressure on Venus is 91 times that of Earth. An atmospheric probe that was sent was crushed.

That's right. I mentioned sending bacteria to the planet once cooling was initiated, to change the composition of the atmosphere. The trick is to bind the Carbon to something that can be percipitated out of the air, and therefore shedding "mass" from the atmosphere. No, I do not know how to genetically engineer a bug to do this, but it seems within the realm of chemical possibility.

2-No moon (tidal necessity)

When you are done using the asteroid for "nudging" Venus around, you park in a rather low orbit around Venus, and voila! You have a moon to generate some tidal action.

3-Exceptionally weak magnetic field

Well, 3 things are possible here:
(a) For small colonies, we create artificial magnetic fields locally, to protect the folks from radiation.
(b) Since we have "spun up" Venus to a 24 hour (or so) rotational speed, we might find that the core of the planet will start generating a magnetic field like the Earth.
(c) If the "moon" we park around the planet is sufficiently massive, tidal effects might help start some "core" sloshing around in Venus, to stimulate magnetic field production.

However, you raise just 3 of many valid points, indicating why we are not about to embark on a Venusian terraforming project any time soon.

[rjsimmon]

That's right. I mentioned sending bacteria to the planet once cooling was initiated, to change the composition of the atmosphere. The trick is to bind the Carbon to something that can be percipitated out of the air, and therefore shedding "mass" from the atmosphere. No, I do not know how to genetically engineer a bug to do this, but it seems within the realm of chemical possibility.

Even trickier would be finding the right bacteria that could survive in that hostile environment.

When you are done using the asteroid for "nudging" Venus around, you park in a rather low orbit around Venus, and voila! You have a moon to generate some tidal action.

The math for this is fascinating. What would be the required mass and velocity to move Venus to a sustainable, higher orbit? What would be the ramifications of moving the planet to a higher orbit, but not increasing the speed of orbit? Would Venus end up in too eratic an orbit to sustain its place in the solar system? What would that do the remaining inner planets?

Well, 3 things are possible here:
(a) For small colonies, we create artificial magnetic fields locally, to protect the folks from radiation.

Talk about power generation! How many Gigawatts would that take?

(b) Since we have "spun up" Venus to a 24 hour (or so) rotational speed, we might find that the core of the planet will start generating a magnetic field like the Earth.

Number and size of comets required??? The number of trips to the Kuiper Belt would exhaust the resources of Earth. Or, would we just wait for strays???

(c) If the "moon" we park around the planet is sufficiently massive, tidal effects might help start some "core" sloshing around in Venus, to stimulate magnetic field production.

We would need some new oceans. But then, if we chose the right bacteria, oxygen and hydrogen creation could be the proper by-product. Any of those little bugs floating around???

[Williams]

Uh, they are discussing a problem that needs to be addressed ONE BILLION years from now and they acknowledged all the risks. It will not be the same scientists.

However, when I said if you read the article I was not directing that at you just to anyone that read the headline and not the article.

[SunkenCiv]

heh heh...

· join · view topics · view or post blog · bookmark · post new topic ·

[wendy1946]

One thing you need to keep in mind regarding any ideas of terraforming Venus is that Sagan’s “super greenhouse(TM)” theory is a bunch of bullshit. Venus is basically hot because it’s a fairly new planet which simply hasn’t had time to cool off. There’s likely nothing we could possibly do that would cool it in any sort of a hurry.

[Interesting Times]

It's a start.

[Quix]

Lost in the vast quantum spaces between their ears, for sure.

[Quix]

please allow some editorializing . . .

The arrogance of changing earths orbit is truly

[mind bogglingly, galactically, infinitely, off the scale stupidly, terminally cluelessly, retchedly dumbly, horrendously brainlessly, . . . ]

stunning.

[CodeToad]

” If the earth speeds up, it will move to a wider orbit around the sun. “

Too fast and not enough for escape velocity only results in a elliptical orbit. Way close then way far away from the sun. Burn & Freeze, burn then freeze.

[grey_whiskers]

All we have to do is tickle the back of the bottom turtle holding up the earth...

Or, if you're libertarian, you get Atlas to shrug.

Cheers!

[Question_Assumptions]

"This is Corbell for himself, Corbell for himself. I'm fine. How are you?"

[Old Professer]

And to think I felt silly when I put my wisdom tooth under my pillow...