Is Earth's orbit scarily close to Venus's sultry zone?

[ScienceRocks]

Is Earth's orbit scarily close to Venus's sultry zone?
13 June 2013
Magazine issue 2920. Subscribe and save
For similar stories, visit the Solar System , Editorials and Astrobiology Topic Guides

IT USED to be called Earth's twin. With much the same size, mass and composition as our home, Venus was a lush jungle planet in the popular imagination of the early 20th century. Muggier than Earth, perhaps, but otherwise not so very different.

That, of course, turned out to be entirely incorrect. Venus's surface is sweltering and its atmosphere suffocating: its being closer to the sun made a dramatic, not an incremental, difference to its fate.

That realisation has all but extinguished hopes of finding a twin for any earthly environment in our solar system. (Iced-over oceans on moons of the gas giants are almost our last hope.)

So the search for Earth's twin has moved much further afield: to the families of other stars. Work to identify the "habitable zones" in which such planets might exist has turned up some startling insights – not just about them, but also our own planet (see "Goodbye, Goldilocks: is life on Earth heading for an earlier demise?").

If the latest models are accurate, Earth and Venus really might have been twins, had the orbit of one been just a tiny bit different. But rather than two clement Earths, there might have been two infernal Venuses. That's a doubly humbling thought.

Is Earth's orbit scarily close to Venus's sultry zone? - opinion - 13 June 2013 - New Scientist

With the increase of solar energy we may not be favorable for life a few tens of millions of years from now. The models show that we're very close to the edge of this habitual zone...

I'll look for that report that shown us to be on the edge.

 

[ScienceRocks]

Earth is closer to the edge of Sun's habitable zone

Mar 25, 2013 12 comments

The Earth could be closer than previously thought to the inner edge of the Sun's habitable zone, according to a new study by planetary scientists in the US and France. The research also suggests that if our planet moved out of the habitable zone, it could lead to a "moist greenhouse" climate that could kick-start further drastic changes to the atmosphere.

A star's habitable zone is the set of orbits within which a planet could have liquid water on its surface – and being within this zone is considered to be an important prerequisite for the development of life.

The current consensus is that the Sun's habitable zone begins at about 0.95 astronomical units (AU), a comfortable distance from the Earth's orbit at 1 AU. However, this latest work by James Kasting and colleagues at Penn State University, NASA and the University of Bordeaux suggests that that inner edge of the zone is much further out at 0.99 AU.

Earth is closer to the edge of Sun's habitable zone - physicsworld.com

NOW THIS IS REASON TO BE VERY CAREFUL!

 

[gslack]

Is Earth's orbit scarily close to Venus's sultry zone?
13 June 2013
Magazine issue 2920. Subscribe and save
For similar stories, visit the Solar System , Editorials and Astrobiology Topic Guides

IT USED to be called Earth's twin. With much the same size, mass and composition as our home, Venus was a lush jungle planet in the popular imagination of the early 20th century. Muggier than Earth, perhaps, but otherwise not so very different.

That, of course, turned out to be entirely incorrect. Venus's surface is sweltering and its atmosphere suffocating: its being closer to the sun made a dramatic, not an incremental, difference to its fate.

That realisation has all but extinguished hopes of finding a twin for any earthly environment in our solar system. (Iced-over oceans on moons of the gas giants are almost our last hope.)

So the search for Earth's twin has moved much further afield: to the families of other stars. Work to identify the "habitable zones" in which such planets might exist has turned up some startling insights – not just about them, but also our own planet (see "Goodbye, Goldilocks: is life on Earth heading for an earlier demise?").

If the latest models are accurate, Earth and Venus really might have been twins, had the orbit of one been just a tiny bit different. But rather than two clement Earths, there might have been two infernal Venuses. That's a doubly humbling thought.

Is Earth's orbit scarily close to Venus's sultry zone? - opinion - 13 June 2013 - New Scientist

With the increase of solar energy we may not be favorable for life a few tens of millions of years from now. The models show that we're very close to the edge of this habitual zone...

I'll look for that report that shown us to be on the edge.

Ah in tens of millions of years we most likely won't be here any longer.

 

[SSDD]

So who is responsible for this....CO2 or Bush?

 

[ScienceRocks]

Our understanding of the habitable zone has interested as we study other solar systems. We may not have hundreds of millions of years as we once thought with the slow increase in solar flex.

 

[bripat9643]

Our understanding of the habitable zone has interested as we study other solar systems. We may not have hundreds of millions of years as we once thought with the slow increase in solar flex.

In 1000 years we'll have the technology to move the Earth 1 million miles further away from the sun.

Problem solved.

 

[mamooth]

Yep. We could start moving the earth now. It would be a supermassive engineering project, but it's doable with current tech.

Basically, you put a mass behind the earth. Not in orbit around the earth, just sitting behind the earth, relative to the sun. Since it's not in orbit, earth's gravity would be sucking it in. To counter that, you'd put a gigundous solar sail on it. Pressure from the solar wind would push the sail to counteract the earth sucking it in, and it would stay in place.

Meanwhile, the tiny gravity of that mass would very slowly, over thousands of years, tug the earth's orbit outward. The system sort of converts the solar wind into a gravity leash tugging on earth.

However, before we try that, there's the matter of how the inner planets are kind of synchronized in orbits now, but it's a chaotic system, and little nudges might butterfly effect into big changes over a million years. Like Mercury going more and more elliptical until its orbit crosses earth's, which would be a bad thing.

 

[ScienceRocks]

I'd like to do that to Venus too

Maybe we could use the dwarf planet Cere to move the earth and maybe the other big Asteroid to do the same to venus.