So many planets, so few telescopes

November 8, 2012 by Michael Lemonick

Over the last few weeks, astronomers announced not one but two extraordinary discoveries in the ongoing search for planets orbiting stars beyond the sun. The first was a world about the size of Neptune, 5,000 light-years away, whirling around in a solar system with four stars. It's something like Luke Skywalker's home world of Tatooine in the "Star Wars" movies, except that fictional planet sported only two suns.

The second was an Earth-size planet right next door in the Alpha Centauri system - three stars that orbit one another not thousands or hundreds but a mere four light-years from our solar system. That makes it not just the nearest "new" planet ever found but the nearest that could be found. (It isn't for nothing that so many sci-fi authors - although not George Lucas - have set their tales in the Alpha Centauri system.) With a surface temperature of 2,000 degrees or so, this planet's surface is probably molten, but its presence implies, tantalizingly, that there could be more.

All of this is exciting and wonderful, but it's a far cry from the discoveries astronomers thought they would be making by now. Back in the mid-1990s, when the first "exoplanets" () were found in distant star systems, NASA talked boldly about the new generation of powerful telescopes it was planning to build, in large part to hunt for alien worlds, especially those in balmy, life-friendly orbits.

By the early 2000s, something called the Space Interferometry Mission, or SIM, was going to measure the nearly imperceptible side-to-side wobbles caused by the gravity of Earth-size , tugging their stars first one way, then the other as they orbited. By 2007, the original version of the , designed to be bigger and more powerful than the Webb scope now under construction, was supposed to be taking direct images of , along with other astronomical duties. And by 2020 or so, the Terrestrial Planet Finder, or TPF, would be imaging true Earth "twins," scanning their atmospheres for gases that might betray biological activity.

As of today, however, SIM has been canceled; the smaller, less powerful Webb will launch by 2018 perhaps; and the TPF has been put on the back burner, maybe permanently. These disappointments have partly to do with NASA's ever-shrinking science budget, but SIM and TPF were also torpedoed by internal squabbling among scientists who disagreed about the best designs and about whether SIM was vital or unnecessary.

Yet even without the scopes they hoped for, astronomers are finding planets by the carload, using the Kepler space telescope, launched in 2009, and even small, ground-based instruments. Rather than wait for NASA to come through with expensive new toys, innovators like Harvard University's David Charbonneau; William J. Borucki of the NASA Ames Research Center in the Bay Area; and Michel Mayor at the Geneva Observatory in Switzerland kept pushing existing the science to its limits, and then pushing again.

Borucki, for example, lobbied for more than a decade to have NASA approve his Kepler mission, which is designed to look for the faint dip in light that occurs when an exoplanet passes in front of its star. It was a simpler and cheaper planet discovery method than SIM and the rest, but the agency kept finding fault with his proposal, so he answered their objections and re-proposed it five times. Since its launch, Kepler has found more than 2,000 probable planets.

Charbonneau chose to look for dips in starlight as well, but from the ground; his innovation was to look at dim red stars, figuring a dip in light would be easier to spot if the star was dimmer to begin with. And Mayor took his 1990s-era instruments, which look for subtle changes in a star's color as a planet yanks it back and forth during the planet's orbit, and refined them beyond what anyone thought was technologically possible. It was his team that found the Alpha Centauri planet.

The result: While the telescope makers dithered, the roster of planets has exploded, from just one in 1995 to 800 known , and an additional 2,300 - provisionally identified by Kepler - that are waiting to be confirmed by further observations. Some of these provisional planets come from an unlikely source: Citizen scientists on the website, scouring Kepler spacecraft data, were the ones who flagged the new four-star planet in Kepler's database, after the professional scientists had missed it.

This sort of scrappy ingenuity has kept the field of exoplanetology hopping with new discoveries, astonishing even the most seasoned scientists with the endless surprises the cosmos seems to hold. But just imagine the discoveries that would be happening with a NASA science budget that could keep up with astronomers' dreams.

Explore further: Scientists discover planetary system orbiting Kepler-47

More information: Michael D. Lemonick is a senior writer at Climate Central and the author of "Mirror Earth." He wrote this for the Los Angeles Times.

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1 / 5 (3) Nov 08, 2012
Bush and his hand picked genius O'Keefe blew 40 billion dollars on their Moon Mars And Whatever program before it was quickly euthanized, but that 40 billion would come in handy about now.
1 / 5 (1) Nov 09, 2012
At the South Pole there is descending air and ice.
Place a circular rail on the ice. Build a bridge over the rail on the diameter. Make the diameter as large as possible.
The bridge is on wheels and rotates about the centre of the circle.
Water is sprayed from the bridge to build a giant convex lens of clear ice.
The lens is polished to perfection.
Aluminium is sprayed on the Ice.
Carbon fibres are sprayed onto the aluminium. Piezo crystals are placed on the carbon layer.
A supporting frame of your choice is laid over the crystals.
A current is passed through the aluminium to heat it and separate it from the ice.
Hydrogen is forced between the aluminium and the ice.
The structure floats away and is guided to the side, where it is allowed to flip over and settles on the surface.
Repeat the process.
The next structure is not allowed to flip over but is brought down onto the first and the edges are sealed with a gentle explosive paste..
1 / 5 (1) Nov 09, 2012
Two linear accelerators and rocket are attached to the outside.
The construction is filled with hydrogen.
It is floated to the edge of space. The rocket takes the structure up to an altitude where the linear accelerators' thrust is sufficient to overcome atmospheric drag.
The steady thrust of the accelerators take the vessel out of Earth's gravitational well, where the gentle explosive separates the construction. The two halves then go to L4 and L5.
A camera is placed at the focal point of the lens. Distortions are corrected by the piezo electric crystals.
The direction of the two giant lenses is co-ordinated to yield binocular views of exoplanets.
This information is presented in an auditorium on the earth as a halographic model.
5 / 5 (1) Nov 09, 2012
Sounds pretty scifi. But when you do a reality check on it it won't work for about a dozen reasons.

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