Bummer - it turns out that "super Earths" might not be super great for life as we know it.

Astronomers have long puzzled over the enigma of planets that are a bit bigger than Earth, but smaller than small gas giant planets like Neptune. Some have theorized that these planets might be terrestrial, like Earth -- perhaps covered with deep oceans due to them being a bigger target for water-bearing asteroids.

A new study published by the Royal Astronomical Society casts doubt on that theory, instead showing that super Earths might be a lot more like "mini Neptunes" than anything else.

Astronomers studied seven well-known super Earths with hydrogen-rich atmospheres, like the gas giants in our solar system. They wanted to see if energy from their host stars would cause enough gas to escape for the planet to eventually be terrestrial, with a thin atmosphere like Earth's.

We already know that Hot Jupiters, massive gas giants that orbit scorchingly close to their stars, lose a lot of gas due to the intense heat of their stars, sometimes trailing giant plumes of gas that have been torn away from their atmospheres. The thought was that perhaps smaller, super Earth size planets would eventually lose enough gas to morph into something more like Earth.

But the authors of the study came to the conclusion that super Earths just won't lose enough gas in their lifetimes to ever be terrestrial, especially cooler ones that would orbit in the habitable zones of their stars.

It's a downer for folks who were hoping that super Earths could represent a huge class of potentially habitable planets, but it's important to remember that large, terrestrial moons of planets in the habitable zone could still harbor life as we know it.

So, instead of "super Earths", will scientists start calling these planets "mini Neptunes"? I'll keep you posted.

A couple months ago we featured NASA scientist Olivier Guyon on PlanetQuest. Guyon won a MacArthur "genius" grant, a major achievement that speaks very highly of the potential that Guyon's colleagues see in him.

Guyon is really interested in bringing the message of exoplanets to the people, as illustrated in this great TEDYouth talk he delivers about how to find exoplanets. His talk begins at about 3:15. Later in the podcast, JPL Mars celebrity Bobak Ferdowsi also talks to the group.

Kepler may be the exoplanet mission you hear most about these days, but for the past few years, it hasn't been the only one.

Sadly, that may be changing soon.

The CoRoT mission, built by our friends over at the French space agency CNES, has suffered a major computer failure that's prevented scientists from downloading data from the telescope. They are currently in the midst of trying to remedy the problem, but if it persists, the mission is doomed.

The CoRoT spacecraft is significant for several reasons -- for starters, it was the first dedicated exoplanet mission ever, predating the launch of Kepler by a little over two years.

CoRoT looks for exoplanets using the same method as Kepler, watching for stars that dim in brightness when planets move directly in between them and the telescope. It took just 3 months for the mission to find its first exoplanet discovery, and so far it's made 25 exoplanet finds. Like the Kepler mission, you can tell that a planet is a CoRoT discovery if it has the word CoRoT in the name, i.e. CoRoT-2 b

Unlike Kepler, which takes a broad look at a huge group of stars in the sky, CoRoT has focused on studying a small number of planets in-depth. The CoRoT planets represent some of the most well-studied exoplanets yet. It's also made breakthroughs in the fields of astroseismology, helping scientists understand how stars work.

Should this be the end for CoRoT, it leaves behind a rich field of about 600 exoplanetary candidates, the result of over five years of observing the sky. Follow-up with other instruments will help scientists determine if these are actual exoplanet discoveries, so the number of CoRoT planets could increase even after the mission hardware has gone dark.

CoRoT's demise is a bummer and also a pretty poignant reminder of how tough it is to keep sensitive instruments running in the harsh environment of space. Kepler itself has had some hardware problems -- one if its reaction wheels, which allows the telescope to accurately point itself at the sky -- went offline earlier this year. Another wheel failure would mean the end of the mission.

Still, when it comes to exoplanet finding, space is most definitely the place. CoRoT and Kepler's many discoveries and huge fields of candidates are proof positive that finding planets is much more successful with instruments that don't have to contend with the effects of Earth's atmosphere. Here's hoping that future exoplanet space missions will build upon the amazing, ground breaking work of the CoRoT mission.

I may work for a website called PlanetQuest, but I myself am not a planet hunter as much as I am a planet-communicator, helping the scientists of NASA get word of their discoveries out to everyone else.

But there's a way the amateurs among us can get our hands dirty with real Kepler data and help with the hunt for new exoplanets. It's called Planet Hunters, and amateur exoplanet enthusiasts like you have already used it to discover real exoplanets in the Kepler data.

The gist of Planet Hunters is pretty simple. The program serves up slices of Kepler data, and you use the sophisticated pattern-recognizing software in your brain to look for signs of light curves, which can be the signatures of transiting exoplanets. First, you're asked a couple questions about the general shape of the light data, then you're given the chance to highlight any events that you think look like exoplanet transits.

Finding exoplanets in Kepler data isn't always a cakewalk. Stars are often anything but quiet and docile, with many variations in their light radiation over time.

It sounds easy, but picking out the light curves can be tricky. First of all, stars don't shine with light that's nearly as constant as what looking out into the night sky might lead you to believe. Many of the stars I looked at had wild shifts in light intensity, yo-yoing up and down over the course of days or climbing in intensity over the course of weeks. In fact, one of the big discoveries of the Kepler mission has been its finding that our sun is actually a pretty docile star compared to most other stars its size.

Because transit events only last a couple of hours, I had to toss these light curves, leaving the data for a more powerful computer than I to process.

My search continued for about 15 minutes - calling up new targets from the computer, squinting and changing the scale and finally determining that what I was seeing wasn't a light curve from an exoplanet.

And then I saw it.

Here's the find that got me excited: SPH10087115 has a light curve in its data that looks a lot like an exoplanet.

A light curve with the telltale signs of exoplanet activity, with a steady baseline interrupted by sharp drops. The signature of an exoplanet making its brief passage in front of its star and blocking some of the light.

Granted, it make take some time before my "discovery" is confirmed, and there's a decent chance that Kepler scientists have already spotted this light curve and either logged it as a discovery, or found out that it's a "false positive" like an eclipsing binary star. I'll be watching the discussion page on my discovery to see if others find the same result.

My (possible) discovery! If this is a real planet, it has a pretty rapid period, orbiting once every couple days. Inset is a close-up of the light curve.

But the feeling of finding my own exoplanet transit was pretty awesome, and gives me a glimpse into how challenging it can be for astronomers to pick planets out of the mountains of Kepler data -- and how cool it can be to realize you're looking at the light signature of a distant exoplanet, orbiting its star.

For generations, the idea of finding exoplanets was considered a dream at best. Now, you can hunt for them in your pajamas. Sure, we might not have lightsabers and hover-boards yet, but I'd say that the future is very much upon us.

For more information and to hunt for your own planets, check out Planet Hunters.

Attention Scrabble players: here's a good word to have in your back pocket: "Exosyzygy."

Sometimes, exoplanets pass directly between their host star and the Earth. That very fortunate coincidence is called a "transit". Literally thousands of potential exoplanet discoveries have been made using this method.

Sometimes, more than one planet will transit its star. That's even cooler because it allows scientists to get info about multiple planets at once. And because multiple planets tug on each other as they orbit, astronomers can use the variations in the timing of the transits to prove, with a very high degree of confidence, that what they're looking at is indeed a bonafide set of exoplanets.

But do you call an event where two planets happen to not only cross in front of their host star as they orbit - but also cross one in front of the other, as a group of astronomers recently discovered?

New Scientist reports that there's some disagreement as to what's the proper nomenclature for such an event. Among the potential names are "double transit," "planet-planet eclipse," and, curiously, "exosyzygy."

Exosyzygy? What?

The term is a play on the word "syzygy," which is a term applied to events where three space objects, like stars and planets, arrange in a straight line. The spring tide is a phenomenon when the sun, moon, and Earth are all arranged in such a fashion.

Having trouble pronouncing the word? Don't worry - astronomers believe that finding planets that not only transit, but line up as they do so is extremely rare, so don't expect to hear it used very often.

Read the rest of the New Scientist article here. See the text of the discovery paper here.

Guest blogger Connie Lu is an undergraduate at the University of Chicago who spent her summer with NASA's Exoplanet Exploration Program at JPL in Pasadena, California. For more information about student internships at JPL, visit http://careerlaunch.jpl.nasa.gov/.

How did you find this internship?

During winter break, all of my friends seemed to know what they were doing. They were all applying for internships in investment banking, the U.N., tech startups, and I was lying in bed, reading poetry. Not that there was anything wrong with reading poetry‚ I love poetry‚but I had no idea how I was going to find a summer job that I enjoyed. So I made a list of subjects that interested me: poetry and literature, physics, music, etc. Then I started trawling Google for relevant organizations with internships that pertained to each one. JPL was the only NASA center that I was really dreaming about interning at, but I'd already dismissed as being a little far-fetched. I submitted my resume to the general pool anyway. Months later, I got a call from JPL asking if I was still available for the summer. How could I have said no? Lessons learned: strange things happen, and you should let them. Don't limit yourself.

What got you interested in space?

Please don't laugh at this story. Both my parents are computer engineers, so there's been a computer of some sort in the house for as long as I can remember. In elementary school, we had this big desktop that I played Putt-Putt and Oregon Trail on. The screensaver (I promise this is relevant) was the one with the star field, and when I got bored during piano practice (which was often), I'd turn around and look at it and the bookcase. I'm not sure why I thought looking at them would help me escape the bench sooner, but logical reasoning develops with age, and I was young. So one day it finally occurred to me that the screensaver looked like a window progressing further into a star field. Wait, what, stars were in 3-D? So I became obsessed with the local San Jose Tech Museum and the Exploratorium, started reading more, asked my parents irritating questions. When I found out that there existed actual pictures of space, thanks to Hubble, that just really cemented it all. I hadn't realized it was so beautiful. And that was that, and now I'm irritating JPL scientists and engineers with my questions instead. I'm also a volunteer with the telescopes at the Adler in Chicago, so though space and physics didn't really pan out as a course of study or a career path, they're still in my life, and I'm happier for it.

I knew that planets outside of our solar system existed, and I knew about all of the basic components to the science behind them‚for example, spectroscopy, gravitational lensing, accretion, etc. But I had no idea of how planets were discovered, how many had been discovered, what they were like, or that star shades existed. Speaking of which, star shades are unbelievably cool. Probably the favorite thing I've learned about in these past ten weeks. Or maybe it's that the scientists and engineers at JPL are figuring out the logistics of directly imaging exoplanets that are both extraordinarily distant and dim in comparison to their host stars. The idea that we can see photographs of exoplanets is unbelievable to me.

What's the most astounding thing you've learned during your time here? What is something poetic you've learned about the universe?

Ever? In freshman year, my physics teacher went on a brief tangent that amazed me, and still does -- that entropy is irreversible, and everything will die. I know that sounds morbid, but the finality of it all is incredibly poetic‚ and it's already been addressed in poetry. Robert Frost's "Fire and Ice" is one of his best-known: "Some say the world will end in fire, / Some say in ice." As for what I've learned here, researching and writing about exoplanets has made me realize how incomprehensibly large the universe is. I know the scale of the universe and the Earth's relative inconsequence is also a common topic that people like to write about‚ Carl Sagan, to name a big one‚Äîbut it's for good reason. Transience and death are two of the few topics that are hard to exhaust.

At the University of Chicago, you're majoring in English and Economics. How do you stay interested in such disparate majors?

I think of it that way to stay focused: my English readings and papers as fun, or as close as academic work can come to fun, and Economics coursework and problem sets as tasks. Love and work.

How would you describe the atmosphere at JPL?

I ride the bus to work and sometimes laugh at the thought that most of the strangers I'm sitting next to or exchanging "Good morning" with are likely to be both very brilliant and among the best in their fields. The atmosphere on lab is similar. It feels like a college campus filled with adults who happen to work on space‚ complete with cafeterias. Part of the MSL team is working in the basement of the building I'm in, and one day I saw one of the lead flight engineers slide down the stair railing while carrying on a conversation. I wouldn't say that's typical, but JPL's the kind of place where that can happen and not be considered as totally irreverent or out of place.

How did you feel about the people you met?

The scientists and engineers I've talked to are some of the most patient people I've ever met. Everyone is humble to almost a ridiculous extent, and nobody has a superiority complex about their prior accomplishments. I got to meet the principal investigator on Hubble's WFPC-2 camera, one of the major scientists involved in correcting the telescope mirror's spherical aberration, and he would just go on these amazing, completely offhand tangents about that work.

How did it feel to be here during the Curiosity landing?

It was unbelievable. I'm trying not to exaggerate or be too excessively hyperbolic, but it was unbelievable. I already couldn't believe that I was going to be working at JPL for the summer, and then I got here and of course the landing -- not its success, but experiencing it -- was so much better than I'd imagined. I was with a lot of other people from JPL that night, watching the landing at the Civic Center, and when the control room confirmed a safe landing, the auditorium burst into spontaneous cheering and applause and a standing ovation. The woman next to me was sobbing. That was a little unnerving, but it was sweet, and it really illustrated how inspiring the successful landing was. A few of my friends were abroad, and one brought back a newspaper from Tunisia with Curiosity's landing on its front page for me. Everyone on lab was grinning the day after MSL landed. I'm so glad that I got to witness it all. Seeing the control room where everything took place in 230/the Space Flight Operations Facility was definitely a highlight of this internship as well.

Guest blogger Joshua Rodriguez is the editor of NASA's PlanetQuest website.

Every few months, the NASA Kepler mission science team releases an updated database chock-full of light curves and planet candidate information. It's become something of an event for the many astronomers who comb the data to follow up on possible planet discoveries.

Two separate teams in the past couple of weeks have announced 41 new confirmed exoplanets, sifted out of the massive Kepler data archives. Jiwei Xie at the University of Toronto released a paper with details about 24 new exoplanets in 12 separate solar systems, while a team led by Jason Steffen at the Fermilab Center for Particle Astrophysics announced 27 planets orbiting 13 stars.

Most Kepler confirmations are made using ground-based telescopes, which use the radial velocity technique to confirm that possible Kepler discoveries are indeed real planets. But these newest discoveries were confirmed using what are called Transit Timing Variations.

A lone exoplanet orbiting a star will transit, or pass between the Earth and its star, on a very regular schedule. But the presence of other planets in a solar system can change the timings of those transits, as the planets pull on one other, speeding each other up and slowing each other down.

From those variations in timing, astronomers can confirm that a particular Kepler light curve is an actual exoplanet observation and not something else, like one star moving in front of another. This level of confirmation is what separates a "confirmed" Kepler discovery from a "candidate" one.

It's a cool find because it means that many Kepler planets may be able to be confirmed without additional ground-based observation, which can be a time-consuming process. We might start to see the many Kepler candidates become confirmed at a quicker pace, as scientist refine techniques like TTV and dig deeper into Kepler's treasure trove of data.

Guest blogger Joshua Rodriguez is the editor of NASA's PlanetQuest website.

One of the coolest things about Curiosity's first images of the Martian surface is, pinkish tint aside, just how familiar everything looks. If you've spent time in the deserts of Earth, you've seen scenery like this before — craggy mountains thrusting out above a dusty landscape strewn with rocks and boulders. The few pictures we have of the surface of Venus show similar features. Despite the massive differences between these three planets, certain ties seem to bind us with the rest of the rocky planets and moons in our solar system.

The key difference between Earth and these other worlds, of course, is that Mars, Venus, Ganymede, Triton, and the rest of the rocky bodies in the solar system are completely devoid of beachfront property — severely lacking the lakes and rivers and oceans of liquid water that are Earth's signature. Instead, the rest of the solar system appears mainly to be a bleak tableau of hellish deserts and frigid expanses of ice, interrupted by the occasional volcano or hydrocarbon lake.

So when you consider that humans spent years imagining that Mars was full of canals and the Moon a hunk of cosmic Havarti, the findings of those first planetary missions must have seemed like kind of a bummer. Five missions of Apollo astronauts found nothing particularly friendly on the lunar surface, the few probes that managed to land on Venus barely survived more than an hour apiece, and even Carl Sagan was said to have been disappointed when the first images of Mars from Viking 1 showed an unfriendly expanse of red rocks stretching into the distance. With success came disappointment — we've reached other worlds, only to find that there's nobody there.

The few spacecraft that managed to land on the surface of Venus found that the planet's surface wasn't exactly people-friendly. This photo was taken by the Russian Venera-13 mission in 1982. The spacecraft lasted for about two hours on the Venusian surface.

Consider this: barely 20 years ago, scientists wondered if other stars even had planets at all — and many had resigned themselves to thinking that if they did, we'd never find them. Ten years later, dozens of exoplanets had been discovered, but they were all massive, gas giant planets like Jupiter, many arranged in punishingly hot orbits that practically grazed the surfaces of their stars. We'd found planets, but they were so alien and unlike Earth that scientists wondered if planets were common, but friendly ones like ours were not.

Flash forward to 2012 — 17 years after the first exoplanet discovery. Recent findings have estimated that there are more planets in the galaxy than stars. A cosmos that many astronomers once thought was barren has revealed itself to be practically chock-full of planets.

Not only does the galaxy appear to be crammed with planets and solar systems, but the Kepler mission's broad planet-finding net has found that small, rocky planets are likely to be much more common than big ones like Jupiter. Which means that the pictures we're seeing from Curiosity could be representative of millions, if not billions of similar viewpoints on planets strewn across the Milky Way.

And if even a small percentage of those rocky worlds happens to be the right distance from their stars and have the right mix of volcanic activity, stellar radiation, and liquid water to support life as we know it?

Let's just say that beachfront property, lakeside retreats, and lush, Earth-quality real estate might not be as rare in the universe as we might have once thought.

Finding those planets will take time, and it will be even longer before realtors are selling prime parcels on alien planets.

But if the greatest astronomical disappointment of the 20th century was finally reaching other worlds, only to discover them barren and lifeless, then perhaps the greatest accomplishment of the 21st is finding that our own solar system is just the beginning — one outpost in a galaxy teeming with possibility.

Guest blogger Joshua Rodriguez is the editor of NASA's PlanetQuest website.

If you follow the search for other Earth-like planets, you've probably heard of the so-called "Goldilocks zone," the area around a star where life as we know it could exist.

The current definition of the habitable zone around a star is pretty simple – it's the range of temperatures where liquid water – an essential factor for life as we know it – can exist.

"The problem is that an exoplanet likely needs more than just liquid water to harbor complex life," says Paul Mason, a scientist with New Mexico State University and the University of Texas at El Paso. "For example, we know that UV rays from the sun can destroy DNA. We are looking at habitable niches that exist around some single and binary stars."

Mason and Joni Clark have found that Earth-like habitability, one that takes into account other factors besides water, such as UV radiation and planetary synchronization times. "We find Earth-like conditions may be maintained on a planet orbiting a close binary; twin K-stars, for much longer than is possible in the solar system" he explains.

By examining habitable niches where conditions are most Earth-like, Mason's new description is more restrictive than previous models, but likely more realistic. "We get a better perspective on whether or not an exoplanet might have complex life when we combine as many Earth-like factors as possible."

Mason's research has also found that some binary star systems may be able to harbor habitable exoplanets. "A pair of stars that are cooler than the sun wouldn't emit as much UV radiation and have much longer life-times," he says. "A planet at around 90% of the Earth's distance from the sun might be able to harbor life orbiting such a pair of twin stars."

Mason has also researched how tidal factors – the pull of a star's gravity on the planets in its orbit – can influence potential habitability. "A planet that experiences too much tidal force could be a bad place for life," he explains. "Jupiter's moon Io, for example, experiences severe tidal forces that make it a very volcanic world with no water."

Some tidal forces may be important for life or at least beneficial to life. Mason hopes that future research will be able to more clearly target follow-up studies on potential planets with complex life.

Guest blogger Joshua Rodriguez is the editor of NASA's PlanetQuest website.

One of the most revolutionary space missions ever launched, Kepler has astounded exoplanet scientists with its massive amount of data on thousands of stars, many of which could harbor exoplanets.

Most of the work of the Kepler science team has been processing this data in order to make it useful for scientists across multiple disciplines, from exoplanet hunters to astronomers who study stars.

Erik Petigura, a second-year graduate student at the University of California, Berkeley, has taken a new approach to dealing with the "firehose" of Kepler data.

"The Kepler science team has a challenge because they have to produce data for a lot of different people," Petigura explains. "You have astronomers looking for small planets, for long-period planets, for stellar oscillations ...it's a broad audience, because different signals have different timescales. A hot Jupiter transit happens once a day, whereas an Earthlike transit happens once a year."

Petigura's approach to Kepler data processing is to focus specifically on the narrow range of timescales he's looking for – in this case, small, Earth-size planets orbiting at distances from their star similar to Earth's. "By tossing out everything else, I make the data I'm working with simpler," Petigura says.

Petigura says that this narrower approach can help all astronomers using Kepler's data – not just those looking for other Earths. "Every astronomer has a timescale of interest, whether it's very short or much longer," he says. "By throwing out all the data that doesn't fit to that timescale, scientists can 'scratch their own itch' and process the data in a way that's more efficient."

This approach has already helped Petigura, with the help of the Kepler science team, discover a flaw in the Kepler data that could obstruct the detection of the smallest exoplanets. "I noticed a pattern of noise that we eventually traced to the cycling of heaters in the spacecraft," Petigura explains.

Petigura hopes that his approach to Kepler data processing will help others who are looking for specific kinds of targets in the mission's data. He's also hopeful that he'll be able to use this method to better pick out the small planets that he's really looking for. "I'm trying to move beyond the low-hanging fruit in the Kepler dataset and find the small planets that may be buried in the data."