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Can someone get me the radius of this planet? I would like to calculate the actual gravity on the surface. Because I plan on visiting there.
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Michael Laine's profile photoNathaniel Johnson's profile photoMays Overton's profile photoMichael Simmons's profile photo
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Well it is 4.5 times the size of earth. But I was more worried about the 28 day orbit around the sun. That has to be one fast moving planet. 
 
3 suns, very cool. 28 day years, not a problem, just means seasons are two weeks long (assuming the planet has any). As for size, I do believe they mean mass. Two things have have the same size and very different masses, such as a ballon and a basketball. Assuming that the planet has the same density as ours, it would only have 2% more radius. Thus we would actually weigh 3.75x as much, so I would weigh over 630 pounds. That is a problem, especially if we want to take off again after landing there. To have the same surface gravity as ours the planet would need about 450 times the volume of Earth, 250 times the surface area. ... Right, +Mays Overton ?
 
Usually planets that big havent the same mass
 
I also read that particular solar system is low in high density materials such as iron. Which is why they didn't think a planet would be there. 
 
Well I think they are measuring mass - they know it's there because of the pull it has on the nearby star. Probably they can't see it to determine its actual radius, at least not yet. If there are is a lack of high-density materials then perhaps it could have a large size, water, maybe even a decent atmosphere. But I would be afraid that any life that might evolve on it would never leave due to the sheer cost of escaping its gravity. Could we bring a space elevator with us?
 
+Nathaniel Johnson - I've been working on this for 11 years. There are 4 kinds of Space Elevators:
1) Free-floaters
2) Rotators
3) Centripedal
4) Gravity Assist

Each has their advantages and disadvantages. But yes, in general, we can probably build our system just about anywhere. So when you get there, let us know, and we'll be your contractor for this. :-) www.liftport.com
 
Shouldn't you be able to calculate he gravity on the planet from the mass? They found the planet, and it's mass, in the first place by measuring the "wobble" of the sun caused by the planets gravity? I'm not the engineer here so I don't know. I only have to deal with earth gravity. Hehehe. 
 
According to Newton, gravity is a function of mass over distance, where distance is squared. Thus being a little farther away from the center of gravity, such as being on the surface of a larger, less dense planet, provides significantly less gravitational force.
 
+Michael Laine , it's a great surprise to be talking to someone so dedicated to space elevators. Did your company have a booth at the RoboGames in California around 2006? I may have talked to you or a company like you while we were competing.
 
even if you weighed a little more, excellent excuse for exoskeleton suits! Though it would still be quite a strain on your inner body workings.
And in the reading I've done, I'm not quite sure if they did mean Mass or not. I need to find some of the actual reports; the media tends to miss-use terms.
 
Hi +Nathaniel Johnson - Yes, I went to the RoboGames, in San Francisco. I think it was earlier, though, perhaps in 2004 or 2005. If it wasn't me, that you spoke with, I'd guess it was Ben Shelef of the Spaceward Foundation. I used to be on the Board of Directors, and helped get NASA to fund that prize money for the elevator competitions.

We went into hibernation when the economy collapsed in 2007. But recently re-started - and this time, with a plan for the Moon. Our design uses current Commercial Off The Shelft (COTS) technology (rockets, ribbons, communications, etc) that can have an Elevator on the Moon "...before this decade is out." We'd love to have your help and support!
 
+Mays Overton , very true! Yet at around four gravities and above you would have to worry about unconditioned people passing out, regardless of outside assistance. And +Michael Laine , I would certainly not mind being involved. Looking at your website, I could do so by contributing to your blog?
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