Tag: kepler space telescope

Alien Spotting by 2020?

alien-worldWith recent observations made possible by the Kepler space telescope, numerous planets have been discovered orbiting distant stars. Whereas previous observations and techniques could detect exoplanets, scientists are now able to observe and classify them, with the ultimate aim of determining how Earth-like they are and whether or not they can support life.

Combined with advanced astronomical techniques, the latest estimates claim that there may be are up to 50 sextillion potentially habitable planets in the universe. With their eyes on the next step, the scientific community is now preparing to launch a bevy of new space telescopes that can peer across the universe and tell us how many of those planets actually harbor life.

TESSOne such telescope is NASA’s Transiting Exoplanet Survey Satellite (TESS), which will launch in 2017. While Kepler was focused on a single patch of sky with around 145,000 stars, TESS will be equipped with four telescopes that keep track of around 500,000 stars, including the 1,000 nearest red dwarfs. TESS is expected to find thousands of orbiting, Earth-sized-or-larger planets around these stars.

But to find out whether or not any of those planets actually house life, another sophisticated telescope needs to be employed – the James Webb Space Telescope.Whereas TESS is Kepler’s successor, the James Webb Space Telescope – a joint NASA/ESA/CSA venture – is the planned successor for the Hubble Telescope and is due to launch in 2018.

TESS_Space_Telescope_Mirror37-640x425The JWST has a primary mirror that’s about five times larger than Hubble’s (pictured above), which means it can resolve much fainter signals, locating stars and other objects that have never been seen before. Because it primarily operates in the infrared band (whereas Hubble was tuned towards visible light), the JWST will also be able to see through dust clouds into hidden areas of space.

The JWST’s scientific payload includes a spectrometer that’s sensitive enough to analyze the atmosphere of distant planets. By measuring light from the parent stars, and how its reflected in the planets atmospheres, it will be able to determine if there are life-supporting elements and evidence of biological life – such as oxygen and methane.

TESS_comparisonBecause these planets are light years away, and because the reflected light is incredibly dim, the James Webb Space Telescope will only be able to do this for large planets that orbit red and white dwarfs. Still, that leaves thousands or even millions of candidates that it will be able to observe, and determine whether or not they are already inhabited by extra-terrestrial life.

And last, but not least, there’s the New Worlds Mission, which aims to put a Starshade – which is essentially a big flying space umbrella – into space. This disc would then fly between the James Webb Space Telescope and the star its observing, blocking out large amounts of light and the result “noise pollution” from nearby bright stars that the JWST isn’t observing.

Starshade_1280x720_H264With the Starshade in place, the JWST would be able to probe thousands of nearby planets for signs of life and return data to Earth that is of far greater accuracy. The New Worlds Mission is currently in the prototyping stage, but NASA hopes to procure the necessary funding by 2015 and and launch it within the JWST’s own lifetime.

Because of all this, it is now believed that by 2020 (give or take a few years) we will have the ability to directly image a distant planet and analyze its atmosphere. And if we find methane or another biological marker on just one planet, it will completely redefine our understanding of the universe and the lifeforms that inhabit it.

The answer to the question – “are we alone in the universe?” – may finally be answered, and within our own lifetime. And in the meantime, be sure to enjoy this video of the Starshade space umbrella, courtesy of New Scientist.


Sources: extremetech.com, wired.co.uk, newscientist.com

News from Space: First Earth-Sized Exoplanet Found!

kepler78bFor the past three and a half years, the Kepler space telescope has been hurtling through space and searching the Milky Way for signs of of other planets orbiting distant stars. In that time, Kepler has identified many Earth-like exoplanets, many of which reside within our own stellar neighborhood. However, it has found only one planet in recent months that is Earth-sized.

That planet is known as Kepler-78b, the existence of of which was recently verified by NASA scientists at Cape Canaveral. Of all the planets discovered beyond our Solar System, this one is both rocky in composition and weighs in at roughly 1.2 times Earth’s mass. Beyond that, however, the similarities between this planet and our own end.

kepler78b2In addition to having an orbital period of 8.5 hours, the planet also rotates around its parent star at a distance of about 1.5 million kilometers (approx. 93205 miles). Basically, this means that Kepler-78b is thirty to forty-five times closer to its Sun than Mercury is to ours, and experiences a full year in under nine days. This makes Kepler 78b an extremely hostile environment, unsuitable for life as we know it.

Andrew Howard, of the University of Hawaii at Manoa’s Institute for Astronomy and the lead author on one of two papers published in Nature magazine about the discovery of the new planet, said in recent webcast:

We’ve been hearing about the sungrazing Comet ISON that will go very close to the Sun next month. Comet ISON will approach the Sun about the same distance that Kepler-78b orbits its star, so this planet spends its entire life as a sungrazer.

Kepler78b1A handful of planets the size or mass of Earth have been discovered, but Kepler-78b is the first to have both a measured mass and size. At 1.2 times the size of Earth with a diameter of 14,800 km (9,200 miles), astronomers say it has a density similar to Earth’s, which suggests an Earth-like composition of iron and rock. Its star is slightly smaller and less massive than the sun and is located about 400 light-years from Earth in the constellation Cygnus.

Verification of the planet’s existence and characteristics was made by two independent research teams that used ground-based telescopes for follow-up observations. The team led by Howard used the W. M. Keck Observatory atop Mauna Kea in Hawaii. The other team led by Francesco Pepe from the University of Geneva, Switzerland, did their ground-based work at the Roque de los Muchachos Observatory on La Palma in the Canary Islands.

exoplanet_hotAnd while the discovery is exciting, the close proximity of Kepler-78b to its star poses a challenge to theorists. According to current theories of planet formation, it couldn’t have formed so close to its star, nor could it have moved there. Given that its star would have surely been larger when the system was in formation, Kepler-78b’s orbit would have put in inside the swollen star. Hence, the planet’s existence is an enigma.

To make matters worse, Kepler-78b is a doomed world. Gravitational tides will continue to pull Kepler-78b even closer to its star, and eventually it will move so close that the star’s gravity will rip the world apart. Theorists predict that the planet will vanish within three billion years. And while this may sounds like an eternity to us, in astronomical terms it represents a life cut short.

Source: universetoday.com, nature.com

Bad News From Space!

Kepler-telescope-580x448Between the Mars rovers, deep space probes, and long-term plans to mine asteroids and colonize Earth’s neighbors, there’s just no shortage of news from space these days. Unfortunately, not all of it is good. For instance, NASA recently announced that the Kepler space telescope, which was launched back in 2009 for the purpose of identifying Earth-like exoplanets, is suffering from malfunctions and may be broken down.

And in the course of its operational history, it did manage to identify a number of exoplanets that existed within the habitable zones of their parent stars. In fact, it had found a total of 2,740 candidate exoplanets spread across 2,046 stars systems, and a confirmed total of 132 that have the potential to support life. Unfortunately, during the early month of April during its weekly communication, NASA  found that the space observatory was in safe mode, a sign that something was amiss.

keplerAfter looking into the problem, they realized that it had lost its ability to precisely point toward stars because one of the reaction wheels – devices which enable the spacecraft to aim in different directions without firing thrusters – had failed. This was especially bad since last year an different wheel failed, meaning it only had two wheels remaining. The probe needs at least three working in order to properly aim itself, but now that seems impossible.

But the Kepler team said there are still possibilities of keeping the spacecraft in working order, or perhaps even finding other opportunities for different scientific pursuits. Either way, the team is not ready to throw in the towel on the telescope. And since NASA already approved to keep the mission going through 2016, a lot is still riding on it remaining functional.

Charles Sobeck, the Kepler deputy project manager, addressed the team’s efforts to get the telescope working again during their daily briefing earlier in May:

Initially, they did see some movement on the wheel but it quickly went back to zero speed, indicative of internal failure on the wheel. Our next step is to see what we can do to reduce the fuel consumption, as we would like to extend the fuel reserve as long as we can.

In terms of the malfunctioning wheel, he indicated that there are a few things they can still do to get it working again. One possibility is “jigging it” or running it in reverse.

We can try jiggling it, like you’d do with any wheel here on Earth, commanding it to move back and forth, so we can try to bring the wheel back in service. Or perhaps since wheel #2 hasn’t been turned on for eight months, it may come back if we turn it on. It will take us awhile to come up with a plan.

Sobeck also explained they are currently using thrusters to stabilize the spacecraft, and in its current mode, the onboard fuel will last for several months. But they hope to soon put the spacecraft into what is called a “Point Rest State” – a loosely-pointed, thruster-controlled state that minimizes fuels usage while providing a continuous X-band communication downlink. This ought to keep the fuel consumption down to the point where the telescope could keep going for several more years.

kepler47.jpgWhat’s more, the team also indicated that there is still terabytes of information gathered by the probe that has yet to be sifted through. They estimate that it will take at least two years for them to process it all and determine what other exoplanets exist nearby in our galaxy. And as Paul Hertz – NASA’s astrophysics director – put it, with the work it has already performed, Kepler has essentially carried out its task:

We’ll continue to analyze the data to get the science that Kepler was designed to do. Even though Kepler is in trouble, it has collected all the data necessary to answer its scientific objectives. Kepler is not the last exoplanet mission, but the first. It has been a great start to our path of exoplanet exploration.

In the end, its too soon to say if Kepler is deep in space (literally), or just experiencing a lull while her technicians get her back on track. And even if this does prove to be the end of her, the many thousands of planet she managed to identify during her years of service will certainly prove useful to humanity as we begin to set our sights on interstellar exploration and, God willing, colonization. And I imagine more than a few will bare the proud name of Kepler, in honor of her namesake and the telescope itself!

Sources: universetoday.com, Wired.com

Top Five Exoplanets In The Known Universe

Hello again! Boy, I tell ya, it’s good to be back in the swing of things. You know what they say about absence making the heart grow fonder? Well, they also say a few things about being addicted to your devices! But either way, I’m happy to be back in civilization and able to communicate with my friends and colleagues who are, unfortunately, only reachable electronically.

And I’m even happier that people have had a creative outburst while I was away. I miss being able to take part in brainstorming sessions and coming up with new ideas with people. So I was pretty pleased when I came home and found my inbox so crammed full of emails and comments from my writer friends. And, like a plant that’s been deprived of water, their thoughts set my mind aflame with new ideas!

For one, I realized I had yet to discuss NASA’s top 5 Exploplanets in any real detail. Not long ago, it was announced that the planet Gliese 581 g, which is roughly 20 light years from our Solar System, is the most Earth-like planet in this region of the Galaxy, and hence, the most likely candidate for settlement someday. However, this news came as part of a larger story about all the planets, Earth-like or otherwise, that NASA has been confirming the existence of in recent years. Guess I was too busy focusing on how this effecting my writer’s group to expand on how cool these discoveries really are 😉

The table above shows the top five contenders, grouped according to how similar they are to Earth in terms of gravity, atmosphere, distance from their star, and ability to support life. Gliese 581 g, the fourth planet from the Gliese 581 star, ranks as number one with a 92 percent comparison match. Being roughly the same size as Earth, though boasting significantly more mass, it is also thought to have roughly the same gravitational pull. In addition, the astronomer who was intrinsic in it’s discovery, Steven Vogt, indicated that it is a prime candidate for extra-terrestrial life.

The second candidate, at 85%, is Gliese 667C c, a planet which orbits a red dwarf roughly 22 light-years away. It is so named because it’s parent star is part of a triple star system, or a trinary. Since c is estimated to be at least 4.5 times as massive as Earth, it has the honor of being designated a “Super-Earth”, and no doubt would have enough gravity to make even a world-class athlete feel overwrought from the simple task of walking.

Third is Kepler-22 b, an exoplanet which was spotted by NASA’s planet-hunting Kepler space telescope in 2009. An 81% match to Earth, this world is another “Super-Earth” which is speculated to have an atmosphere and climate which could be hospitable to Earth creatures. Unfortunately, this bad boy is over 600 light years away, making it a pretty poor candidate for settlement anytime soon.

Fourth up is HD 85512b, another super-Earth which orbits the orange dwarf Gliese 370, which is roughly 35 light-years away. At a relatively reasonable distance, and a 77% match to Earth, this planet could be a suitable candidate for colonization one day. NASA already estimates that its average surface temperature and presence within the star’s “Habitable Zone” would be within tolerable limits. Hopefully the gravity is the same!

And coming in at fifth place is the second planet to come to us from the Gliese 581 system, the fifth planet known as Gliese 581 d. As the above table shows, g and d are both within the systems Habitable Zone and could be made to support human populations, provided certain requirements (i.e. the existence of water, suitable temperatures and gravity) were met. When it was first discovered in 2007, it was dismissed as being “too cold” to support life. However, subsequent atmospheric modelling studies suggest that it could be habitable provided its atmosphere is capable of generating a Greenhouse Effect, as Earth’s is.

Many question how and why the discovery of exoplanets will benefit humanity. As one of my friends (hi Rami!) asked me recently, what good is it to colonize worlds do us if our problems remain? I argued that it would ensure our survival, but quickly realized that I’d need to make a better case if I was going to prove that point. As a curve-ball, I asked him to consider the possibility that maybe Earth itself, as we’ve made her in the past 15,000 years, could be the problem…

Naturally, that statement requires clarification. But that’s something for another time. Right now, all I am hoping for is that the discovery of habitable planets within humanity’s reach will mean either the possibility of extra-terrestrial life, or the option of planting the seed of humanity in a distant solar system. The implications of either would be mind-blowing, and I for one feel privileged to live in a time when such possibilities might be coming true!