Super Earth...now we know who's making those circle crops lol

[dionysus]

New 'super-Earth' found in six-planet system

CBC News
An international team of astronomers has discovered what they are calling a new 'super-Earth,' which is seven times the mass of Earth and has the right conditions to support life.

An international team of astronomers has discovered what they are calling a new "super-Earth," which is seven times the size of Earth and has the right conditions to support life.

Called HD40307g, the new planet exists in a zone of a nearby star and is part of a six-planet system.

Scientists had already known about the star and its other three uninhabitable planets but after using an instrument that was more sensitive to wavelengths, they were able to discover another three, including the super-Earth.

A report, appearing in Astronomy and Astrophysics, said the super-Earth exists in an area that supports liquid water and is in the outermost orbit from the star.

Its orbit around the host star is at a similar distance to Earth's orbit around our Sun and also gets a similar amount of energy from the star that Earth receives from the Sun. This means there is a stable atmosphere to support life. As well, the planet is likely to be rotating on its own axis as it orbits the star, producing a daytime and night-time effect, much like Earth.

"The longer the orbit of the new planet means that its climate and atmosphere may be just right to support life," said Hugh Jones of the University of Hertfordshire, which participated in the research.

"Just as Goldilocks likes her porridge to be neither too hot nor too cold but just right, this planet, or indeed any moons that it has lie in an orbit comparable to Earth, increasing the probability of it being habitable."

The planet orbits the star in about 200 Earth-days and now joins a growing list of 800 known planets beyond our solar system.

The super-Earth and its two sister planets were previously undetectable until the team used the Harps instrument at the European Southern Observatory's facility in Chile. The instrument detects tiny changes in the colour of a star's light triggered by a planet's gravitational tug.

Lead author of the paper, Mikko Tuomi, said the instrument allowed for increased "sensitivity" and enabled the team to identify three new planets.

 

[Zepher]

Its 12.30am here, and I should have been asleep hours ago, and am just about to doze off, but this sounds like an astronomical find ( no pun intended... lol )

Stuff like this has always interested me, would be nice to know in our lifetime whether there is indeed other life out there. Will read the paper tomorrow ( please provide a link Cap'n ) and then comment again when I am more awake

 

[dionysus]

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ad nauseum

 

[chayton]

You all can come visit when I move there.

 

[Tirilej]

You all can come visit when I move there.

I would love to...but how is the weather there? You know I need it to be healthy for me

 

[skiny]

7 times the size of Earth? The gravitational pull would be crazy.

Imagine the escape velocity.



I didn't do the math. I'm just goofing around.

 

[P.V.]

It actually looks earth like.

 

[skiny]

It's fun to imagine what the planet would look like but I doubt any of us will ever get to see. Astronomers aren't even looking at the planet itself since planets give off no light of their own. If you're close enough you can see light from stars reflecting off planets but certainly not from 42 light years (about 250 trillion miles) away.

I'm not entirely sure how they do it but scientists can deduce whether or not a planet or planets orbit a star by how much the star wobbles. The math is way beyond me. I'm also unsure of how they know the planet spins. It's kind of interesting that the star is smaller and cooler than ours but the planet is closer to it than we are to the sun. It says the planet would be about 60% cooler than Earth. That's pretty chilly but we have life in some of the coldest regions of our planet.

It's the size that interests me. If we were close enough to visit that planet and actually landed on it's surface, I doubt we'd ever get back off. You couldn't bring enough fuel to reach escape velocity and even if you did, the planets atmosphere would probably burn up anything going fast enough to breach it.

 

[Balthazar]

It's the size that interests me. If we were close enough to visit that planet and actually landed on it's surface, I doubt we'd ever get back off.

Actually, we would. Especially if we have the technology to get there in the first place Seriously though, surface gravity is related to radius and mass (mass divided by the radius squared), and not size. That planet could have the exact same surface gravity as Earth.

Think of black holes, they are tiny but you sure as hell wouldn't come back

 

[skiny]

Actually, we would. Especially if we have the technology to get there in the first place Seriously though, surface gravity is related to radius and mass (mass divided by the radius squared), and not size. That planet could have the exact same surface gravity as Earth.

Think of black holes, they are tiny but you sure as hell wouldn't come back

Gravity is caused by mass. Size is only relevant in regard to how far the surface is from the center of the planet. Now if we're talking about an "Earth like planet" we should assume a solid surface which probably means an iron core (or mostly iron.) It would take a great deal more "matter" to create a solid planet 7 times the size of Earth. More matter equals more mass. Once gravitational pull is no longer strong enough to compress the planet any smaller you end up with a relatively fixed size but with that much more matter the density at the core would be much greater. A denser core means more mass at the center and a stronger gravitational pull.

Putting all that aside, even if the core density was the same as the Earth (which I think would be impossible) the entire planet itself, which is much larger than Earth has a gravitational pull and the difference in distance from core to surface between the two planets is probably negligible in comparison to the enormous amount of mass between the core and surface.

 

[Balthazar]

Gravity is caused by mass. Size is only relevant in regard to how far the surface is from the center of the planet. Now if we're talking about an "Earth like planet" we should assume a solid surface which probably means an iron core (or mostly iron.) It would take a great deal more "matter" to create a solid planet 7 times the size of Earth. More matter equals more mass. Once gravitational pull is no longer strong enough to compress the planet any smaller you end up with a relatively fixed size but with that much more matter the density at the core would be much greater. A denser core means more mass at the center and a stronger gravitational pull.

Putting all that aside, even if the core density was the same as the Earth (which I think would be impossible) the entire planet itself, which is much larger than Earth has a gravitational pull and the difference in distance from core to surface between the two planets is probably negligible in comparison to the enormous amount of mass between the core and surface.

Like I said, surface gravity is caused by mass in relation to the radius. A giant Earth would have the exact same surface gravity than a tiny Earth, as long as the mass/radius stays proportional.

Jupiter is 300+ times more massive than Earth, yet surface gravity is only twice Earth's. If Jupiter had the same mass as it has now but was Earth's size, everything would get absolutely crushed and nothing could ever escape from there.

Surface gravity ≠ gravitational pull

 

[skiny]

Like I said, surface gravity is caused by mass in relation to the radius. A giant Earth would have the exact same surface gravity than a tiny Earth, as long as the mass/radius stays proportional.

Jupiter is 300+ times more massive than Earth, yet surface gravity is only twice Earth's. If Jupiter had the same mass as it has now but was Earth's size, everything would get absolutely crushed and nothing could ever escape from there.

Surface gravity =/= gravitational pull

Jupiter is a gas giant. Earth is almost 5 times denser than Jupiter. A solid planet 7 times the size of the Earth could not possibly have the same mass as the Earth. Terrestrial planets have roughly the same composition. Mostly Iron core, silicate surface. For a planet to be 7 times larger and be made of roughly the same thing it's going to have roughly 7 times the mass.

In fact, now that I think of it, if it's 7 times "larger" than the Earth it's more than likely going to have much more mass because the additional gravitational pull from the increased mass would compress it more than the Earth is compressed. It would probably have more than 7 times as much mass and be compressed to 7 times the size.

 

[Balthazar]

Jupiter is a gas giant. Earth is almost 5 times denser than Jupiter. A solid planet 7 times the size of the Earth could not possibly have the same mass as the Earth. Terrestrial planets have roughly the same composition. Mostly Iron core, silicate surface. For a planet to be 7 times larger and be made of roughly the same thing it's going to have roughly 7 times the mass.

In fact, now that I think of it, if it's 7 times "larger" than the Earth it's more than likely going to have much more mass because the additional gravitational pull from the increased mass would compress it more than the Earth is compressed. It would probably have more than 7 times as much mass and be compressed to 7 times the size.

It doesn't matter if a planet is 10,000 more massive than Earth because if its radius is also 10,000 larger then the surface gravity will be the exact same.

I'm not arguing, I'm not debating, this isn't my opinion, it's a scientific fact:

Recently-discovered planet, Gliese 581 c, has at least 5 times the mass of Earth, (...) it should have a radius approximately 50% larger than that of Earth. Gravity on such a planet's surface would be approximately 2.2 times as strong as on Earth.

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See? 5 times the mass of Earth but since the radius is 50% bigger then surface gravity is only 2.2 times as strong as Earth. If the radius would have been 5 times bigger then it would be 1:1. But if the radius would be the same as Earth then you'd end up with a constant 5g on the surface.

In a nutshell, radius and mass cancel each other.

 

[skiny]

It doesn't matter if a planet is 10,000 more massive than Earth because if its radius is also 10,000 larger then the surface gravity will be the exact same.

I'm not arguing, I'm not debating, this isn't my opinion, it's a scientific fact:


See? 5 times the mass of Earth but since the radius is 50% bigger then surface gravity is only 2.2 times as strong as Earth. If the radius would have been 5 times bigger then it would be 1:1. But if the radius would be the same as Earth then you'd end up with a constant 5g on the surface.

In a nutshell, radius and mass cancel each other.

5 times more mass but only .5 times bigger isn't exactly canceling each other out. You're talking about 50% bigger having 5 times as much mass. That's a pretty drastic increase in mass for a planet that's only 50% bigger. That means that it is much denser. The mass has to come from somewhere and like I said, a terrestrial planet with 7 times the mass that Earth has would be much more dense and have a much stronger surface gravity.

I never said it would be 7 times more. If it had 10,000 times the mass and was 10,000 times the size it wouldn't be very dense. It would probably be a gas giant.

Following the math you posted which is correct the gravitational pull would be somewhere between 2 and 3 times the Earth's gravitational pull. So what would escape velocity be? Between 25 and 35 km/s? I guess from orbit it would be less.

 

[Balthazar]

Following the math you posted which is correct the gravitational pull would be somewhere between 2 and 3 times the Earth's gravitational pull. So what would escape velocity be? Between 25 and 35 km/s? I guess from orbit it would be less.

All we know is that the Super Earth has 7 times the mass of Earth. With the radius unknown, it's simply impossible to tell if gravity is greater, lower or the same as planet Earth.

Again, to calculate surface gravity you need the radius and the mass. It's just a simple mathematical formula skiny

or see post #9


When you look at the formula, you quickly realize that for the same M, the bigger the R, the smaller the g.

 

[skiny]

All we know is that the Super Earth has 7 times the mass of Earth. With the radius unknown, it's simply impossible to tell if gravity is greater, lower or the same as planet Earth.

Again, to calculate surface gravity you need the radius and the mass. It's just a simple mathematical formula skiny

or see post #9


When you look at the formula, you quickly realize that for the same M, the bigger the R, the smaller the g.

Obviously we don't know the radius since we can't see it. We're going under the assumption (for fun) that it is an "Earth like" planet with an iron core and a silicate crust. Based on that we can guess what the radius would be if we knew the mass. If we were going under the assumption that it was made of hyrdogen and helium it would obviously be a lot larger but wouldn't be nearly as interesting since it wouldn't be able to support life.