It's Confirmed. We now Know of More Than 5,000 Exoplanets

An artist view of countless exoplanets. Credit: NASA/JPL-Caltech

This week the official count of known exoplanets crossed 5,000. On the one hand, there isn’t anything special about 5,000 vs 4,900 or 5,100, but on the other hand, crossing this threshold is an indication of how far we’ve come, and how quickly things will change in the future.

Continue reading “It's Confirmed. We now Know of More Than 5,000 Exoplanets”

An Exoplanet is Definitely Orbiting Two Stars

Artist's impression of Kepler-16b, the first planet known to definitively orbit two stars - what's called a circumbinary planet. The planet, which can be seen in the foreground, was discovered by NASA's Kepler mission. Credit: NASA/JPL-Caltech/T. Pyle

Remember that iconic scene in Star Wars, where a young Skywalker steps out onto the surface of Tatooine and watches the setting of two suns? As it turns out, this may be what it is like for lifeforms on the exoplanet known as Kepler-16, a rocky planet that orbits in a binary star system. Originally discovered by NASA’s Kepler mission, an international team of astronomers recently confirmed that this planet orbits two stars at once – what is known as a circumbinary planet.

Continue reading “An Exoplanet is Definitely Orbiting Two Stars”

Based on Kepler Data, There’s a 95% Chance of an Earth-Like Planet Within 20 Light-Years

Credit: NASA

In the past few decades, the study of exoplanets has grown by leaps and bounds, with 4296 confirmed discoveries in 3,188 systems and an additional 5,634 candidates awaiting confirmation. Because of this, scientists have been able to get a better idea about the number of potentially-habitable planets that could be out there. A popular target is stars like our own, which are known as G-type yellow dwarfs.

Recently, an international team of scientists (led by researchers from the NASA Ames Research Center) combined data from by the now-defunct Kepler Space Telescope and the European Space Agency’s (ESA) Gaia Observatory. What this revealed is that half of the Sun-like stars in our Universe could have rocky, potentially-habitable planets, the closest of which could be in our cosmic backyard!

Continue reading “Based on Kepler Data, There’s a 95% Chance of an Earth-Like Planet Within 20 Light-Years”

Machine Learning Algorithm Scoops up 50 New Exoplanets

Credit: NASA/JPL-Caltech

Advances in technology are having a profound impact on astronomy and astrophysics. At one end, we have advanced hardware like adaptive optics, coronographs, and spectrometers that allow for more light to be gathered from the cosmos. At the other end, we have improved software and machine learning algorithms that are allowing for the data to be analyzed and mined for valuable nuggets of information.

One area of research where this is proving to be invaluable is in the hunt for exoplanets and the search for life. At the University of Warwick, technicians recently developed an algorithm that was able to confirm the existence of 50 new exoplanets. When used to sort through archival data, this algorithm was able to sort through a sample of candidates and determine which were actual planets and which were false positives.

Continue reading “Machine Learning Algorithm Scoops up 50 New Exoplanets”

An Earth-Sized World Orbiting in its Star’s Habitable Zone Was Found in Older Kepler Data

Illustration of Kepler-186f, a recently-discovered, possibly Earthlike exoplanet that could be a host to life. (NASA Ames, SETI Institute, JPL-Caltech, T. Pyle)

To date, astronomers have confirmed the existence of 4,144 extrasolar planets in 3,074 systems, with a further 5,094 candidates awaiting confirmation. The majority of these planets were found by the Kepler Space Telescope, which spent nine years (between May of 2009 and February of 2018) monitoring distant stars for transit signals – where a planet passing in front of a star causes a dip in brightness.

And yet, even though it is now defunct, the data that Kepler accumulated over the years continues to lead to new discoveries. For instance, a transatlantic team of researchers recently found a signal in Kepler‘s archival data that eluded detection before. This signal indicates that there is a second planet orbiting Kepler-1649, an M-type red dwarf star located 302 light-years away.

Continue reading “An Earth-Sized World Orbiting in its Star’s Habitable Zone Was Found in Older Kepler Data”

A New Way to Measure the Age of the Milky Way

Artist’s impression of the warped and twisted Milky Way disk. Credit: Chen Xiaodian/Kavli Institute of Astronomy and Astrophysics

Like many other spiral galaxies in the Universe, the Milky Way Galaxy consists of two disk-like structures – the thin disk and the thick disk. The thick disk, which envelopes the thin disk, contains about 20% of the Milky Way’s stars and is thought to be the older of the pair based on the composition of its stars (which have greater metallicity) and its puffier nature.

However, in a recent study, a team of 38 scientists led by researchers from Australia’s ARC Centre of Excellence for All Sky Astrophysics in Three Dimensions (ASTRO-3D) used data from the now-retired Kepler mission to measure starquakes in the Milky Way’s disk. From this, they have revised the official estimates on the age of the Milky Way’s thick disk, which they conclude is around 10 billion years old.

Continue reading “A New Way to Measure the Age of the Milky Way”

Phew! James Webb passes its final thermal vacuum test. Still on track for 2021

Illustration of NASA's James Webb Space Telescope. Credits: NASA
Illustration of NASA's James Webb Space Telescope. Credits: NASA

Once it is deployed to space, the James Webb Space Telescope (JWST) will be the most sophisticated and advanced space telescope in operation. Carrying on in the tradition of Hubble, Kepler, and Spitzer, the JWST will use its advanced suite of infrared imaging capabilities to study distant exoplanets, learn more about the Solar System, and study the earliest galaxies in the Universe.

After numerous delays, NASA announced last summer that the much-anticipated JWST would be ready to launch by 2021. And in what is admittedly a very nice change of pace, NASA recently indicated that this is still a go! According to their latest update, the JWST has just completed its final vacuum test and is on track for launch in March of 2021.

Continue reading “Phew! James Webb passes its final thermal vacuum test. Still on track for 2021”

This is Kepler’s Final Image

MATLAB Handle Graphics. Credit: NASA/Ames Research Center

On October 30th, 2018, after nine years of faithful service, the Kepler Space Telescope was officially retired. With nearly 4000 candidates and 2,662 confirmed exoplanets to its credit, no other telescope has managed to teach us more about the worlds that exist beyond our Solar System. In the coming years, multiple next-generation telescopes will be deployed that will attempt to build on the foundation Kepler built.

And yet, even in retirement, Kepler is still providing us with impressive discoveries. For starters, NASA started the new year by announcing the discovery of several new exoplanets, including a Super-Earth and a Saturn-sized gas giant, as well as an unusually-sized planet that straddles these two categories. On top of that, NASA recently released the “last lighty” image and recordings obtained by Kepler before it ran out of fuel and ended its mission.

Continue reading “This is Kepler’s Final Image”

It’s Over For Kepler. The Most Successful Planet Hunter Ever Built is Finally out of Fuel and Has Just Been Shut Down.

NASA's Kepler space telescope, shown in this artist's concept, revealed that there are more planets than stars in the Milky Way galaxy. Credit: NASA
NASA's Kepler space telescope, shown in this artist's concept, revealed that there are more planets than stars in the Milky Way galaxy. Credit: NASA

It’s been quite a tumultuous time for space telescopes lately! Less than a month ago, the Hubble Space Telescope went into safe mode after experiencing a mechanical failure with one of its gyroscopes (which has since been remedied). Shortly thereafter, the Chandra X-ray telescope went into safe mode as well, and for similar reasons. After three days, it’s operations team managed to get it back in working order as well.

And now, after nine years of service, NASA has officially announced that the Kepler Space Telescope will be retiring. With no fuel remaining to conduct its science observations, NASA has decided to leave the telescope in its current safe orbit (well away from Earth). Far from being a sad occasion, Kepler’s retirement is an opportunity to reflect upon the immense accomplishments of this telescope and how it revolutionized the study of exoplanets.

Continue reading “It’s Over For Kepler. The Most Successful Planet Hunter Ever Built is Finally out of Fuel and Has Just Been Shut Down.”

There are so Many Water-Worlds Out There

Artist's concept of Earth-like exoplanets, which (according to new research) need to strike the careful balance between water and landmass. Credit: NASA

Ever since the first exoplanet was confirmed in 1992, astronomers have found thousands of worlds beyond our Solar System. With more and more discoveries happening all the time, the focus of exoplanet research has begun to slowly shift from exoplanet discovery to exoplanet characterization. Essentially, scientists are now looking to determine the composition of exoplanets to determine whether or not they could support life.

A key part of this process is figuring out how much water exists on exoplanets, which is essential to life as we know it. During a recent scientific conference, a team of scientists presented new research that indicates that water is likely to be a major component of those exoplanets which are between two to four times the size of Earth. These findings will have serious implications when it comes to the search for life beyond our Solar System.

Continue reading “There are so Many Water-Worlds Out There”