Super-Earths Discovered Orbiting Nearby, Sun-Like Star

likuidkewl writes "Two super-earths, 5 and 7.5 times the size of our home, were found to be orbiting 61 Virginis a mere 28 light years away. 'These detections indicate that low-mass planets are quite common around nearby stars. The discovery of potentially habitable nearby worlds may be just a few years away,' said Steven Vogt, a professor of astronomy and astrophysics at UCSC. Among hundreds of our nearest stellar neighbors, 61 Vir stands out as being the most nearly similar to the Sun in terms of age, mass, and other essential properties."

Comments

Yes, nearby

[elrous0]

Yes, a mere 28 light years away. So all we need to do is get in the fastest spacecraft we've ever built and we can be there in just about 150,000 years.

Who's coming with me?!?!?

Re:Yes, nearby

[The Archon V2.0]

Not so much a problem for the folks on the spacecraft, relativity can make the journey very manageable for them. They better not think about returning home to see Grandma though...

So space will be colonized by people with dysfunctional families?

Re:Yes, nearby

[beefnog]

What'd probably happen is about five years (as the travelers perceive it) after launch we'll develop faster-than-light travel and interrupt their journey. Or maybe just let them ride it out as a curious time capsule to cruise by and show buttcheek to.

Re:Yes, nearby

[jamesh]

Not so much a problem for the folks on the spacecraft, relativity can make the journey very manageable for them.

I think we're a long way off building a spaceship that can achieve the speeds where that effect would make any difference.

Re:Yes, nearby

[jbezorg]

So space will be colonized by people with dysfunctional families?

Sorry folks, planet's closed. The six legged moose like creature out front should have told you.

Re:Yes, nearby

[Anonymous Coward]

At .0002c, it would take about 14000 years to get there, but the lucky astronauts would only experience 13999.99972 years. Sign me up!

Re:Yes, nearby

[roc97007]

Why should space be any different?

Re:Yes, nearby

[Judinous]

We aren't as far off as you think. What's important is being able to constantly accelerate during the journey. Slow and steady acceleration wins the race. You're not going to do that with a chemical rocket, but with an on-board nuclear reactor and a few advancements in ion propulsion or vacuum propellers, we could make the trip. We could easily launch a probe to start making the journey in the next five years, if we allocated the budget to do so. Humans could make the trip as well, given the right accommodations--only a few years would be passing on-board. None of the technology to do this is very far-fetched at all, but we just aren't willing to spend the money.

Re:Yes, nearby

[Penguinshit]

That's no moon...

Re:Yes, nearby

[Grishnakh]

If we stick with only 1.0G, then we wouldn't need artificial gravity for the people on board. We could maintain 1.0G acceleration on the way there, then spin the ship around (so the floor is pointing towards the destination) and maintain 1.0G deceleration for the second half of the journey.

The problem is, even if that means the people on board only experience 5-25 years, how much time will pass on Earth before we found out what this exploration team discovers there? (Remember, once they get there after however many years (hundreds? thousands?), they'd have to send their data by radio at light-speed, which would take yet another 28 years.) If we were to pony up the money to finance a mission like this, we, our children, our grandchildren, and our great-grandchildren would never find out the results, if any. We'd probably develop FTL in that time and have a colony already established on any viable planets in the 61 Virgo system before this team even arrived!

As far as I'm concerned, the only way any mission to another star system at low sub-light speeds makes any sense is if you're going to launch a "generation ship", a giant ship with an entire colony on board with everything needed to be self-sustaining indefinitely, so that this ship can travel from star system to star system, radioing back what it finds in each one and continuing until they find a place worth stopping at and establishing a permanent colony. But a ship like this would in itself be a major leap in technology, since we certainly don't have the capability to build such a massive space-based structure that can travel long distances through space, be self-supporting indefinitely, and able to handle any problems it might encounter (micrometeors?).

Re:Yes, nearby

[Gospodin]

That is an ion engine. My back-of-envelope calculations say that accelerating to .0002c and back to rest requires an Isp of about 5300 if you assume a mass ratio of 10:1. (Which is about as high as you can expect with current technology.) You can do a little better with staging, but not orders-of-magnitude better.

If you can improve your Isp to, say, 50,000, which is well beyond current technology, then you could accelerate to almost 0.002c. Relativistic effects won't be really evident until well over 0.2c (at that speed it's only a 2% time dilation). We're not close to rockets that can attain such speeds.

Improving the mass ratio is even less helpful, btw, since that's a logarithmic factor. An Isp of 50,000 with a mass ratio of 100 still only gets you to 0.004c. I suppose it's conceivable that an interstellar ship that needed almost no structure could have an extremely high mass ratio, but you can see how ridiculously high it has to be to matter.

The only way we're going to send starships at relativistic speeds is to use (i) some form of non-rocket propulsion, like solar sails or those reactionless Casimir-effect thrusters or some other exotic method, (ii) something with a truly enormous Isp. Current ion engine tech tops out at about 30,000 s, and even nuclear pulse tops out at 100,000 s.

Re:Yes, nearby

[CrimsonAvenger]

If we stick with only 1.0G, then we wouldn't need artificial gravity for the people on board. We could maintain 1.0G acceleration on the way there, then spin the ship around (so the floor is pointing towards the destination) and maintain 1.0G deceleration for the second half of the journey.

The problem is, even if that means the people on board only experience 5-25 years, how much time will pass on Earth before we found out what this exploration team discovers there? (Remember, once they get there after however many years (hundreds? thousands?), they'd have to send their data by radio at light-speed, which would take yet another 28 years.) If we were to pony up the money to finance a mission like this, we, our children, our grandchildren, and our great-grandchildren would never find out the results, if any. We'd probably develop FTL in that time and have a colony already established on any viable planets in the 61 Virgo system before this team even arrived!

1G = 7 years internal time, 30 years as time is measured on Earth. So you'd be getting messages back with 60 years.

0.01G = 100-odd years internal time, 107 years as time is measured on Earth. Messages back about 210 years after departure.

Note that 1G sustained isn't going to be practical for a very long time, but that 0.01G sustained (for 100+ years) is a maybe within the century.

Note that if we launched a 0.01G ship day after tomorrow, then sometime around 2185 we launched a 1G ship, the 1G ship would get there first.

On the other hand, I don't think a generation ship is entirely beyond the realms of possibility within the next 50 years. Yes, it would require some incredible engineering to get it done. But it wouldn't require as much new technology as one might think - the sheer size allows you to get away with things that aren't practical in a smaller ship. Like lakes, fields, forests, that sort of thing.

Re:Yes, nearby

[CrimsonAvenger]

The problem here is that 1G sustained means your ship will be liveable by humans for those 7 years with no problem. 0.01G is not liveable at all; humans can't survive long-term in microgravity.

And of course it would be impossible to spin the ship, right?

Any ship big enough for a 100 year trip will be more than big enough to spin so that the rim of the ship experiences enough gravity to keep the crew healthy.

Not only that, 100 years is too long; no one will live that long (assuming you launch them when they're 20-25).

I take it you've never heard of the "generation ship" concept?

Humans can't live their entire lives (including their all-important formative years) in a small spacecraft with little social interaction.

And who ever suggested a small spacecraft? If I were designing it, it'd be 20 km long and 5-6 Km in diameter. With a crew of about 100,000.

A generation ship, however, could solve this problem (kids could very conceivably be raised on a giant ship with lakes and forests and a whole functioning mini-society), but as you said, this would require some incredible engineering. Lifting that much material into orbit really needs a space elevator, for starters.

So you DO know about generation ships! Great!

Hint: you don't build a generation ship from Earth. You start with an asteroid, and stock pretty much everything except the lifeforms aboard from other sources than Earth.

Note also that "incredible engineering" really means "expensive". It doesn't necessarily mean "difficult".

And this still doesn't address the gravity problem; those lakes and forests aren't going to work without artificial gravity.

Spin it. If it's six km in diameter, you have to spin it at 0.55 rpm to get 1G on the rim. And note that you have 360 km^2 worth of rim on the ship I described above. With a deck every 100 meters, we're talking a couple hundred thousand hectares at > 0.9G.

Alas, the likelihood of humanity building a generation ship is miniscule.

What passes for government here on Earth can't look far enough ahead. If we KNEW there was an alien species living there, and that they would be willing to give us the secret of FTL if only we sent someone there to collect, we'd still never get one built...

But the only real difficulty with doing so is the drive - the lifesystem, the physical structure, that sort of thing is almost trivial in comparison.

Fishy...

[chocomilko]

Hey! I thought it was supposed to be 70 Virginis.

Something tells me that these astronomers are keeping Virginis 1 through 9 to themselves. Grab your torches and pitchforks, kids.

Re:Fishy...

[Kratisto]

You're mistaken. Virgins one through nine ARE the scientists.

dissapointing

[jocabergs]

High gravity + Close to its star = big fat, sweaty alien women.

  I'll get excited when we find a planet about 93 million miles away from its star, the proper solar light properties for blue skin and near earth gravity. I've always had a thing for blue skinned alien girls.

Re:mmmm

[Daimanta]

How's that? I'm sure that it's possible to find at least 61 virgins on /. In fact, I think you are the right place if you're looking for virgins.

Wow, a confirmation

[MillionthMonkey]

Why is everyone surprised that super-earths are orbiting other stars? I've always wondered that.

Anyway in case anyone hasn't RTFA (or noticed the light-gray on white links at the top of the oklo.com page) you yourself can help them search for nearby earths by downloading the tool at http://oklo.org/downloadable-console/ while you're still unemployed.

Re:mmmm

[JeanBaptiste]

I never said I was straight.

of course since it's the internet, I'm actually a 12/f/CA.

Super War

[Anonymous Coward]

I say it is high time we develop a warp ship capable of carrying the combined military might of the entire planet to this system.

We'll move quickly, from one "Super" Earth to the next, conquering indigenous peoples and enslaving them to toil in our mines until the planet is naught but a smoldering husk, a shadow of what used to be.

Then we'll see who is "Super".

Who's with me!?!

28 light years

[girlintraining]

Yes, a mere 28 light years away. So all we need to do is get in the fastest spacecraft we've ever built and we can be there in just about 150,000 years.

Well, maybe not us, but bacteria could. Or... maybe bacteria came from there, and landed here. Betcha didn't think of that.

Re:mmmm

[TheEmpyrean]

61 Virgins? Can I trade them for 8 slutty broads that know what they're doing?

Re:mmmm

[Kugrian]

/me puts on his robe and wizard hat.

Re:mmmm

[Red Flayer]

Else you could teach the virgins what you like and help them develop their own tastes

FWIW, the two major inputs to their tastes are diet and sanitary practices. I heard vegans taste better.

(Just trying to think outside the box)

Re:Drake's Equation

[reverseengineer]

It's more like that the Drake equation has gone from an relation where all the variables are unknown to one where about half the variables are unknown. Advances in astronomy have allowed us to refine estimates of the number of stars in the galaxy, the fraction of those stars with planets, and the age of the galaxy. Studies like those the article refers to could potentially pin a value down on the "number of planets that could potentially support life per star with planets." The very meaning of that variable, however, depends on what characteristics you would consider necessary to support life.

From the progress of exoplanet searches so far, it does seem likely that some planets will be found that could support life in an earth-like sense (terrestrial with liquid water, at minimum). So, maybe four variables with potentially supportable estimates (and exoplanet searching is in its infancy, so that estimate will develop over time).

But the other variables in the Drake equation? What fraction of "habitable" planets actually develop life? What fraction of those develop intelligent life? Intelligent life that sends out detectable signals into space? And what is the expected lifetime of such civilizations? Values we might assign to those variables would be pure conjecture, with our only evidence being our own anecdote of existence.