On September 14 2011 03:33 Deadpoetic0077 wrote: Would this planet really be life sustaining? Since its 3. whatever times as big wouldnt we be 3. whatever times as heavy?
Depends on the density of the planet.
F = ma = G * M1 * M2 / r^2 a = G * M1 / r^2 = G * (4/3) * pi * r^3 * density / r^2 = G * (4/3) * pi * density * radius G is on the order of 10^-11, so the gravity felt at the surface increases slowly but linearly as the radius increases for planets of equivalent density.
3 times as big does not mean 3 times the gravitational force unless the mass density of the planets is equal.
On September 14 2011 03:33 Deadpoetic0077 wrote: Would this planet really be life sustaining? Since its 3. whatever times as big wouldnt we be 3. whatever times as heavy?
Depends on the density of the planet.
F = ma = G * M1 * M2 / r^2 a = G * M1 / r^2 = G * (4/3) * pi * r^3 * density / r^2 = G * (4/3) * pi * density * radius G is on the order of 10^-11, so the gravity felt at the surface increases slowly but linearly as the radius increases for planets of equivalent density.
3 times as big does not mean 3 times the gravitational force unless the mass density of the planets is equal.
For constant density surface gravity is proportional to the 3rd root of the mass.
But in reality bigger planets will have higher densities, both because they have higher pressure at the core and because they (probably) tend to have more heavier elements.
You can measure the radius of a planet if you can observe a transit (eclipse) and you can measure its mass by looking at the planet's effect on the movement of the star.
I don't know if any super-Earth's density has been measured accurately, but if it hasn't been done yet it will happen in a few years.
Makes me sad... I am, however, excited at the prospect of humanity one day exploring other galaxies and planets. I just wish I could be there to experience it.
On September 13 2011 19:18 Mithriel wrote: One day one of these telescopes will zoom into a planet and see things running/flying around. Imagine the shock the ones watching the first images must get haha.
Its just a matter of time!
The problem with this though is time. Everything we see in the sky is actually X years old depending on how far away it is. Since it takes light 1 year at 186,282 miles per second to travel 6 trillion miles. It is the maximum speed at which all energy, matter, and information in the universe can travel (as far as what is known and accepted anyways). so a telescope uses light(or radio which is also light) obviously to see things.
So since this super earth is 35 light years away (or about 210 trillion miles) we are actually seeing it as it was 35 years ago. And if other planets were discovered that were even further away you might even see them before or after any civilization occurred and totally miss it (even though right now at this exact moment there may be something going on). It's kind of strange to think about that, but that's to give you a small taste of how fucking huge the universe is.
I've actually always wondered how it would look if an object took off from a far distance and traveled in a straight line to us (or at least a straight looking line from our vantage point on our rotating earth, rotating around our sun, which is rotating around our black hole, which is flying through space lol) if you considered the light year thing.
On September 13 2011 19:20 dementrio wrote: Regarding feasible technology for interstellar travel, there was a cold-war era concept for a nuclear-propelled megaship that would achieve speeds up to (iirc) 0.2c, which would make it possible to reach nearby solar system over the course of 1 or 2 generations.
Nuclear-propelled as in, actual atomic bombs explode and haul the ship's ass forward. There are to this date unsolved technological problems in building such a ship but no theoretical impossibility. However, since it would have to be built in space, we can't even start funding such a project until we have a shipyard out there. Very unlikely we'd see even the beginning of such a project in our lifetimes.
It was called project orion if you want to look it up.
Provided you have enough fuel to keep the engine going, you can (in principle) accelerate your ship to speeds arbitrarily close to the speed of light. Since there is no friction force in the vacuum of space, there's nothing to counteract the thrust from the engines.
The principle behind efficient space travel is that you want to shoot stuff out of the rear end of your spacecraft. Conservation of momentum then causes the spacecraft to feel a force pushing it forward. The challenge lies in propelling matter with low mass at high momentum. You want low mass, because for a 35 LY journey, it's a lot of fuel you have to bring. The combination of low mass and high momentum for the propellant means that it has to be accelerated to high energies. (Explosive) combustion is one way of going about this, it's what current spacecraft use. The problem is that you want to focus the propellant to be expelled in a straight line, while blowing stuff up generally has it going in all kinds of directions.
There are some developments in plasma physics that aim at providing a thruster system based on propelling ions at high energies, focussed in a straight beam by electric and magnetic fields. The concept is not new, the "ion thruster" or "ion drive" is a common concept in sci-fi stories, but the technological realization is only now within our grasp.
Regardless, these are all conventional means of propulsion, which means no FTL. Nevertheless, if a journey to another solar system with an earth-like planet took 100 years, then a generation ship with efficient ion-drive propulsion seems like a fantastic endeavour. Unfortunately, I fear that it will require us to actually meet aliens before we can put aside our petty differences and materialistic needs and start focussing on improving ourselves and our understanding of the universe (just like the scenario described in Star Trek, where humanity slowly unites after a bitter third world war after first contact with an alien race).
Space Kite! Would just be a small robot, but basically you'd use light to push the sails :D Too bad most of the universe is dark
On September 13 2011 16:08 Tippecanoe wrote: With current technology how long would it take to travel 30 light years? 300 ish years?
Anybody know how fast a space shuttle travels?
Nasa shuttle travels almost 17500mph so 1 light year would take about 38263 years, 30 light years ... 1147890 years. So little more than 1 million years. methinks
On September 13 2011 19:18 Mithriel wrote: One day one of these telescopes will zoom into a planet and see things running/flying around. Imagine the shock the ones watching the first images must get haha.
Its just a matter of time!
The problem with this though is time. Everything we see in the sky is actually X years old depending on how far away it is. Since it takes light 1 year at 186,282 miles per second to travel 6 trillion miles. It is the maximum speed at which all energy, matter, and information in the universe can travel (as far as what is known and accepted anyways). so a telescope uses light(or radio which is also light) obviously to see things.
So since this super earth is 35 light years away (or about 210 trillion miles) we are actually seeing it as it was 35 years ago. And if other planets were discovered that were even further away you might even see them before or after any civilization occurred and totally miss it (even though right now at this exact moment there may be something going on). It's kind of strange to think about that, but that's to give you a small taste of how fucking huge the universe is.
I've actually always wondered how it would look if an object took off from a far distance and traveled in a straight line to us (or at least a straight looking line from our vantage point on our rotating earth, rotating around our sun, which is rotating around our black hole, which is flying through space lol) if you considered the light year thing.
Life doesn't evolve just like that so 35 years is nothing.
On September 13 2011 16:08 Tippecanoe wrote: With current technology how long would it take to travel 30 light years? 300 ish years?
Anybody know how fast a space shuttle travels?
Nasa shuttle travels almost 17500mph so 1 light year would take about 38263 years, 30 light years ... 1147890 years. So little more than 1 million years. methinks
On September 13 2011 23:41 Probe1 wrote: Aw man I thought this was going to be new instead of a rehash from last month. At 0.27 AU I still think the radiation from Gliese 370 would be too intense for life to exist outside of the (potential) oceans.
On September 13 2011 17:21 HaXXspetten wrote: Cool Now how do we get over there :/
also... why "Super Earth"? lol
A non gaseous planet that is anywhere from 1.9 to 10fold the mass of Earth 1 M⊕ = 5.9722 × 1024 kg. so anywhere between 1.9 M⊕ and 10 M⊕
Anything larger is referred to as a giant planet. Most giant planets will be primarily gaseous (Jupiter).
Though media does use the term Super Earth liberally for flair without adhering to scientific conventions so if it's on CNN it could mean anything.
Anyway, Gliese 370 is 2.11625993 × 1014 miles (36 ly) away. Don't get your hopes up for an exploration trip. Let's say we have a breakthrough in the next ten years (magic) and we can send manned ships at the same speed as probes. So that's 44 miles per second.
To get to this planet it would take 249,000 years. (estimate)
Sorry to be a buzz kill.
1 M⊕ equals the mass of Earth
I doubt that we would even try to send something out that far. Most likely whats going to happen is that eventually we'll have the technology to bend space and get to places extremely fast.
On September 13 2011 19:18 Mithriel wrote: One day one of these telescopes will zoom into a planet and see things running/flying around. Imagine the shock the ones watching the first images must get haha.
Its just a matter of time!
The problem with this though is time. Everything we see in the sky is actually X years old depending on how far away it is. Since it takes light 1 year at 186,282 miles per second to travel 6 trillion miles. It is the maximum speed at which all energy, matter, and information in the universe can travel (as far as what is known and accepted anyways). so a telescope uses light(or radio which is also light) obviously to see things.
So since this super earth is 35 light years away (or about 210 trillion miles) we are actually seeing it as it was 35 years ago. And if other planets were discovered that were even further away you might even see them before or after any civilization occurred and totally miss it (even though right now at this exact moment there may be something going on). It's kind of strange to think about that, but that's to give you a small taste of how fucking huge the universe is.
I've actually always wondered how it would look if an object took off from a far distance and traveled in a straight line to us (or at least a straight looking line from our vantage point on our rotating earth, rotating around our sun, which is rotating around our black hole, which is flying through space lol) if you considered the light year thing.
Life doesn't evolve just like that so 35 years is nothing.
If you didn't realize, he meant that other planets are further away... That could be some million/billion light years
On September 13 2011 05:55 ampson wrote: Now let's get to work on that faster-than light travel? Looks sweet. But why is it called SUPER EARTH?
Cause it's just like Earth.
BUT SUPER
This is what I heard in my head.
The existence of a "super earth" isn't overly surprising, given the vastness of the universe. It's still cool to make progress on finding and learning about them, though. Progress on actually reaching any of them will be a lot slower. Too many humans think on too small of a scale, often centered on themselves. Has a manned spacecraft even gotten out of Earth's gravitational pull? Obviously the moon is within our gravity. I think I heard about some Mars thing, but I think it was just a plan and not something that'd already been sent out.
the name of the planet is HD 85512b, much more creative
To that my brain just goes: "I don't always colonize other planets, but when I do I make sure it's in HD."
On September 13 2011 09:19 hotbreakfest wrote: Currently we can see up to 42 billion light years into space. We are an insignificant speck dust on a speck of dust on a speck of dust on a speck of dust on a grain of sand in the Sahara Desert. I think that says just about enough.
So you explain to me, how a universe that is 13.9 billion years old, can see up to 42 billion light years
it takes light a year to travel a light year(duh) so 42 billion light years it would take 42 billion years.
So if the big bang happened only 13.9 billion years ago, how can we see up to 42 billion light years?
we can't?
I think the last figure was 13.5 billion light years
Imagine how life on another planet 3.6 times as large as earth would look! The muscles on those animals!
On September 13 2011 09:19 hotbreakfest wrote: Currently we can see up to 42 billion light years into space. We are an insignificant speck dust on a speck of dust on a speck of dust on a speck of dust on a grain of sand in the Sahara Desert. I think that says just about enough.
So you explain to me, how a universe that is 13.9 billion years old, can see up to 42 billion light years
it takes light a year to travel a light year(duh) so 42 billion light years it would take 42 billion years.
So if the big bang happened only 13.9 billion years ago, how can we see up to 42 billion light years?
we can't?
I think the last figure was 13.5 billion light years
Imagine how life on another planet 3.6 times as large as earth would look! The muscles on those animals!
Short answer as to why we can see around 47 billion light years away (the furthest image taken so far):
The speed at which the universe is expanding is not constant. Rather, everything in the universe is expanding away from each other linearly proportional to the distance between the objects.
The rate at which the universe is expanding is increasing.
EPT![[image loading]](http://i.imgur.com/vFox7.jpg)
