You are currently browsing the tag archive for the ‘exoplanet’ tag.

Picture2

Well it could always be worse…If you are a little worn out by our planet and its problems, take a moment to consider the tidally locked gas giant planet WASP-76b which lies 640 light years from Earth in the constellation Pisces.  WASP-76b is a bizarre world.  At twice the diameter of Jupiter, the planet is so close to its blazing host star that a “year” lasts only 43 of our Earth hours.  The temperature on the bright side of the planet is 2,400 degrees Celsius–hotter than the surface of some stars.  This enormous temperature combines with the rivers of blistering exotic radiation from the star to shred molecules apart into their constituent atoms.  The super-heated atoms are caught in convection cycles and eventually flow to the planet’s eternal darkside, where they rain down as iron precipitation. How metal is that?

030920_mt_ironrain_feat-1028x579

The WASP system is named for the “Wide Angle Search for Planets,” a British program to discover strange new exoplanets by means of a ground based array of telescopes.  Once they discovered the giant WASP-76b (which is virtually inside the corona of its sun), the team utilized the new “Espresso” spectrographic instrument at the European Southern Observatory’s Very Large Telescope in Chile to study the giant world’s chemical makeup.  The Espresso instrument assays the spectrum of light visible in the infinitesimally small dot of light visible to the Very Large Telescope (I don’t know what Espresso stands, presumably it is some convoluted acronym, but it is the world’s most sensitive spectrometer–not a coffee machine).

rWzAMuCjF3J93nMPaHMH2C

Science of this precision always leaves me agog.  Remember back when I was writing about the new generation of giant super telescopes being built in the Atacama Desert of Chile?  These efforts are now yielding extraordinary discoveries–such as the almost-star WASP-76b.

It will be astonishing to find out even more about such nigh-incomprehensible worlds when the NEXT generation of superscopes are completed…assuming they ever are. The launch of the James Webb space telescope has been pushed back to 2021 because of cost overruns and because it is unclear whether NASA has any launch system they trust sufficiently for the enormously expensive scope (sigh).  Additionally, America’s own massive ground based telescope–the proposed 30 meter scope at Mauna Kea-has become trapped in limbo by the criminal actions of a group of terrorists, hooligans, dolts, and recidivists who despise humankind and hate all knowledge. But we will write more about them later.

58f29888e595225947b1b56f57126ae4.jpg

There are two amazing pieces of space news today to shock and astonish you.  First, we have found a near-analog to planet Earth orbiting a red dwarf star—and it is “only” 11 light-years from our Solar System.  The exoplanet is named  Ross 128b and it is orbiting a quiet red dwarf star (most red dwarves are subject to solar flares which release life cleansing jolts of exotic radiation, but, like our delightful Sun, Ross 128 seems to be much more sedate (perhaps its placid life has something to do with its bland name which makes it sound like a dullard clone friend on an 90s sitcom).  In this age of exoplanet discovery, it is easy to lose sight of what an astonishing find this is, but I grew up in a world with only nine known planets.  Remember back when Ferrebeekeeper was rhapsodizing about weird icy oddballs like Gliese 581 g?  Ross 128B seems like it roughly the same size and temperature as Earth and it is right in our backyard.  Additionally, it is moving towards us, in a mere 78000 years it will be the closest exoplanet to Earth!

Venus_balloon.jpg

The other “news” is more conditional and vague, but no less exciting to me.  NASA has been floating the concept of a balloon mission to Venus.  I have been hoping for more attention to our nearest neighbor (since I harbor fantasies of living there, in the sweet spot above the merciless clouds) a balloon probe to see what the atmosphere is actually like would let us know whether his fantasy is at all workable.   The Soviet Union actually sent some balloon probes to Venus back in the early days of interplanetary exploration, but they were crude things which were not built to last and they told us little.  Let’s do it right this time and find out everything about our mysterious sister planet!  It is going to be a little while before Ross 128B is in range so let’s explore the immediate neighborhood and get to work on living abroad while there is still time!  

planet-young-K2-33b-NASA-artist-2016-e1466502891596

Aww…look: a baby planet!  This is the youngest known exoplanet—a mere 5 to 10 million years old.  It orbits its star every 5 days—a ridiculously short year which puts even Mercury’s 88 day orbit to shame (although, to be fair, the planet is 10 times closer to its star than Mercury is to the sun).  The newly discovered world is approximately 500 light years from Earth.  Researchers discovered the world with the Kepler space telescope (which continues to disgorge a treasure trove of data, even after its primary mission has ended because of mechanical failure).

The planet is thought to be about the size of Neptune.  Since its star, K2-33, is only 10 million years old, the planet is assumed to be younger than that…though who knows.  The strange nature of this system may cause scientists to rethink and refine their models of planetary formation.  It isn’t the sort of thing they expected (though these super-hot giant planets right next to their stars seem to be more common than anyone would have guessed).

An artist's' conception of the planetary sytem of Wolf 1061C

An artist’s’ conception of the planetary sytem of Wolf 1061C

Today Australian scientists announced the discovery of a very interesting exoplanet—a so-called “super-earth” which orbits around the red dwarf star Wolf 1061.  The rocky planet (Wolf1061c) is actually only one of three worlds so far found in the solar system of Wolf 1061, but it is of particular note because it lies in an orbit which allows for liquid water to exist upon its surface.

Wolf 1061 is tidally locked to its star, so one side always faces the red ball in the heavens. It has a mass about 4.3 times that of Earth—so the surface gravity is nearly twice that of Earth. Its “years” are 18 Earth days long.

Perhaps most excitingly Wolf 1061c is “only” 14 light years away (about 84,000,000,000,000 miles).  It is a neighbor!  Perhaps we can use our best telescopes to assay the atmosphere and find out if anything resembling Earth life is there.

Stromatolites at dawn in Shark Bay, Western Australia

Stromatolites at dawn in Shark Bay, Western Australia

This place really exists! Spend a moment imaging what it is like on the surface.    In my fantasy, one side of the world is a vast red desert while the other is a desolation of black glaciers…yet in a twilight ring between the sides there are sludgy water oceans filled with big green and violet pillows of fabulous squashed shapes—the analogs of stromatolites.  Bubbles of gas pour up from these oddly shaped blobs of bacteria-like cells.  Somewhere among the billions of little multiplying alien organisms, a few peptides have changed and the cells begin to exchange genetic material with one another.  They are beginning to reproduce sexually instead of merely dividing.  Life in the ring oceans of 1061c takes a leap forward.  It is all imagination…and yet it may be so.  The universe is vast.  I wish we could find out more about this entire earthlike planet that we only just found.

French Space Program satellite COROT

French Space Program satellite COROT

During the last several years one of the most exciting aspects of astronomy has been data from two orbiting space observatories concerning planets which lie outside our solar system.   The NASA space telescope Kepler discovers such planets by simultaneously measuring the light from thousands of stars for the faint dimming that occurs when a planet passes between the star and Kepler.  The French satellite COROT (“COnvection ROtation and planetary Transits”) finds exoplanets by tracking the slight oscillations in distant stars caused by the gravitational tug of orbiting planets.  The subtlety and elegant precision of both methods is astounding.

Sadly such astonishing engineering seems to have been near the edge of our technological abilities.  Yesterday Kepler went into safe mode (a sort of automatic shut-down triggered by a crisis).  Apparently a reaction wheel (a flywheel used to orient the spacecraft in relation to the stars) failed and Kepler can no longer be aimed properly.  The orbital observatory initially had four reaction wheels—one of which was a spare– however the spare wheel failed in July of 2012 and at least three wheels are required to operate the satellite.  If NASA cannot somehow reactivate the flywheel, then the mission is over.

Kepler Space Observatory

Kepler Space Observatory

Likewise on November 2, COROT suffered from a computer failure which made it impossible to collect data from the satellite and its status remains uncertain.  Most likely it is offline forever.  So our ability to find huge numbers of exoplanets via space observatory has temporarily been halted.

Kepler was launched in 2009 for a four year mission, however the mission was recently extended until 2016 (since it took longer to collect and make sense of the data then initially planned).   At last count Kepler had discovered 132 planets and was monitoring more than 2,700 further candidate planet. As of November 2011, COROT had found 24 new worlds and was screening around 600 additional candidates for confirmation.  Additionally two years of Kepler data has been downloaded but not yet interpreted so post-mortem discoveries may lie ahead.

Planned Transiting Exoplanet Survey Satellite

Planned Transiting Exoplanet Survey Satellite

It is frustrating that the age of almost daily discovery of new worlds has come to a temporary end due to equipment failure, however a new generation of planet finding missions is already on the drawing board.  To quote The Guardian:

The European Space Agency announced last year that it would launch the Characterising Exoplanets Satellite (Cheops) in 2017 to study bright stars with known planets orbiting them. Nasa’s successor to Kepler will be the Transiting Exoplanet Survey Satellite (Tess), which will conduct a survey of planets around more than two million stars over the course of two years.

RIP Kepler and COROT, you discovered so many planets and you will be missed, but your successors will be even greater.

26113942013_-planets

The Atacama Desert (towards the Andes)

The Atacama Desert (towards the Andes)

The Atacama Desert of Chile is the driest place on Earth.  The desert is bounded in the west by the Chilean Coastal Range, which blocks moisture from the Pacific.  On the east of the Atacama run the mighty Andes Mountains which catch almost all the rainfall from the Amazon Basin.  Thus trapped between ranges, the desert receives 4 inches of rain every thousand years.  Because of the dryness, people are very sparse in the Atacama: they are found only at rare oases or as desiccated (but well preserved) mummies lying in pits.

The high altitude, dryness, and lack of nearby cities (with their lights and radio waves) make the Atacama a paradise for astronomers.  On a mountaintop 8000 feet up on the Atacama side of the Andes, engineers and scientists are working to put together one of the wonders of this age.

giant_magellan_telescope_rendering

The Giant Magellan Telescope (hereafter the “GMT”) will be a miracle of engineering.   When it is completed in 2019 it will be larger than any telescope on Earth.  The scope is so giant that it will be mounted in a huge open, moving building (rather than the gun-turret-like buildings observatories are traditionally housed in).  No organization on Earth is capable of making a mirror large enough for the necessary purposes, so seven immense 8.4 meter mirrors are being used together to create a single optical surface with a collecting area of 24.5 meters (80 feet in diameter). The mirrors are the pinnacle of optics: if they were scaled up to the size of the continental United States, the difference between the highest and the lowest point would only be an inch.

giant_magellan_telescope_mirrors

The scope will be much more powerful than the Hubble telescope and take much clearer pictures despite being within the atmosphere of Earth.  In the past decade, telescope makers have used cutting edge engineering to compensate for atmospheric distortions.  To do so they fire multiple lasers grouped around the primary mirrors high into the atmosphere.  These beams of light excite sodium atoms in the sky which fluoresce—creating tiny “stars” of known wavelength, which serve as points of reference for the adaptive optics.  The official website of the GMT further explains the mechanism used to counteract atmospheric turbulence once these benchmarks are obtained:

The telescope’s secondary mirrors are actually flexible. Under each secondary mirror surface, there are hundreds of actuators that will constantly adjust the mirrors to counteract atmospheric turbulence. These actuators, controlled by advanced computers, will transform twinkling stars into clear steady points of light. It is in this way that the GMT will offer images that are 10 times sharper than the Hubble Space Telescope.

The telescope is designed to solve some of the fundamental mysteries about the universe. Scientists hope it will help them find out about the nature of dark matter and dark energy (which are thought to make up most of the mass of the universe).   Astronomers also hope to find out how the first galaxies formed and (perhaps) to ascertain the ultimate fate of the universe.  Most excitingly of all, the telescope should be large enough to peek at some of the exoplanets we are discovering by the thousands.  If life exists anywhere near us, the GMT should provide us with compelling evidence in the next twenty years.

alien-world-red

The National Science Foundation was initially going to contribute heavily to the telescope but, since the United States Government has become indifferent to science and knowledge, other institutions have been forced to pick up the slack.  The scope is being built by a cooperative effort between The University of Chicago, The University of Texas at Austin, The Australian National University, The Carnegie Institution for Science, Harvard University, The Korea Astronomy and Space Science Institute, the Smithsonian Institution, Texas A&M University, & The University of Arizona (so you can probably help out by donating to any of these institutions, particularly the lovable University of Chicago).

giant-magellan-telescope-artists-view-4

62_69_22_earth-lineup_labels

Exciting news from the heavens!  Today NASA has reported that the Kepler mission has discovered 3 new planets in the habitable zones of two distant stars.  Of the thousands of worlds so far discovered, these three are most likely to be habitable.  Best of all the planets are crazy!

Kepler is a NASA space telescope which was launched on March, 2009.  It makes use of an incredibly sensitive photometer to simultaneously & incessantly monitor the brightness of over 150,000 nearby stars.  The brightness of a star dims slightly whenever an exoplanet transits between it and Kepler.  Thanks to Kepler’s inhuman vigilance and robotic ability to perceive nearly imperceptible light changes, we are now discovering thousands of new planets, although most of them are Jovian sized gas worlds.

Kepler Space Telescope

Kepler Space Telescope

The three worlds reported today lie in the habitable zone—the region around a star where water exists in a liquid form (as it does here on beautiful Earth).  Two of the newly discovered habitable zone planets are in a five planet system orbiting a dwarf star just two-thirds the size of the sun which lies 1,200 light years from Earth.   Here is a diagram of the Kepler 62 system.

Kepler 62 System (Art by NASA)

Kepler 62 System (Art by NASA)

Of these five worlds, two lie in the habitable zone, Kepler 62f and Kepler 62e.  Kepler 62 F is most likely a rocky planet and is only 40 percent larger than Earth.  It has an orbit which last 267 (Earth) days.  So far it is the smallest exoplanet found in the habitable zone.  The star it orbits is 7 billion years old (as opposed to the sun which is four and a half billion years old) so life would have had plenty of time to develop.  The other habitable zone planet in the Kepler 62 system, Kepler 62e is probably about 60% larger than our planet.   It is somewhat closer to the star and astrophysicists speculate it may be a water world of deep oceans.

No! Not that sort of Waterworld!

No! Not that sort of Waterworld!

The other new exoplanet Kepler-69c appears to orbit a star very similar to Earth’s sun.  It orbits at the inward edge of the habitable zone (nearing where Venus is in our solar system) so it may be hot.  The planet is estimated to be about 70% larger than Earth, and is also thought to be a water world with oceans thousands of kilometers deep.  I am finding it impossible not to imagine those vast oceans filled with asbestos shelled sea-turtles the size of dump trucks, huge shoals of thermophile micro-squid, and burning-hot chartreuse uber-penguins, but if any life is actually on Kepler-69c, it is probably extremely different from Earth life.

I understand why they are green and have gills, but why are they inside gelatin capsules? (DC Comics)

I understand why they are green and have gills, but why are they inside gelatin capsules? (DC Comics)

Of course Kepler can only find these planets; it is unable to observe very much about them.  In order to do that, humankind will need some sort of huge amazing super telescope.  Speaking of which, tune in next week when I write about humankind’s plans for building a huge amazing super telescope in the Chilean Andes!

I am combining two important science discoveries from this week into one (small) post. This week astrophysicists working on the Keplar program discovered the three smallest known exoplanets (each of which is smaller than Earth) in orbit around a little red dwarf star.  In a completely unrelated field (and scale) of science, biologists in Papua New Guinea discovered the world’s tiniest known vertebrates, two species of miniscule rain forest frogs named Paedophryne amauensis and Paedophryne swiftorum.

Artist's concept of the KOI-961 solar system (Image credit: NASA/JPL-Caltech)

The exoplanets were discovered by a team led by scientists from Caltech who used data from NASA’s mission in conjunction with observations from the Palomar Observatory, (outside San Diego), and the W.M. Keck Observatory (on Mauna Kea in Hawaii). The three planets orbit tiny red dwarf star KOI-961 which has a volume only one-sixth that of our sun (making the star only about 70% bigger than the planet Jupiter). The planets are all very close to their star, and the most distant, takes less than two days to orbit around KOI-961. The three worlds have volumes of 0.78, 0.73 and 0.57 times the radius of Earth.

image credit: Caltech

Red dwarf stars make up four out of five stars in the galaxy, but because they are so small and dim, the Keplar probe has only been assessing a relatively tiny group of red dwarf stars for the possibility of planets.  The fact that studying a small sample of red dwarfs already revealed three terrestrial planets strongly suggests that such planets are commonly found around red dwarfs. John Johnson, of NASA’s Exoplanet Science Institute at the California Institute of Technology in Pasadena summarized the data by saying, “This is the tiniest solar system found so far…It’s actually more similar to Jupiter and its moons in scale than any other planetary system. The discovery is further proof of the diversity of planetary systems in our galaxy.”

An adult Paedophryne amauensis posing on a dime

The discovery of the tiny frogs was made by a team of zoologists in New Guinea led by Chris Austin, a herpetologist trained at LSU.   The team was in the forest of New Guinea when they heard a faint metallic song coming from the leaf litter on the forest floor.  Unable to see the animal producing the faint chorus of “tink” noises, the biologists grabbed up handfuls of leaf litter into a large transparent bag, and began carefully sorting it–expecting a singing insect to emerge.  They were stunned when the miniscule adult frog hopped off a leaf.  The fully grown creature only measured 7.7 millimeters (less than one-third of an inch).

Named Paedophryne amauensis the little amphibians are not just the smallest known frogs–they are also believed to be the smallest free-living vertebrates on Earth (supplanting a minute 8mm long translucent Indonesian carp for that title).  The frogs do not undergo tadpole metamorphosis in water like other frogs, but are born hopping.  They spend their entire lives in the leaf litter where they prey on miniscule arthropods and other invertebrates.  A similar species Paedophryne swiftorum was also discovered by the team, although P. swiftorum frogs were nearly a millimeter larger.

In an interview, the team leader Chris Austin said, “We now believe that these creatures aren’t just biological oddities, but instead represent a previously undocumented ecological guild — they occupy a habitat niche that no other vertebrate does.”

An artist's conception of the earthlike world, HD 85512 b (CREDIT: ESO/M. Kornmesser)

Today it was reported that HARPS, (High Accuracy Radial velocity Planet Searcher) a device operated from the European Southern Observatory’s station atop Mount la Silla in the Andes, has discovered 50 new exoplanets (planets which orbit stars other than the sun).  Sixteen of these new planets are “super-earths” rocky planets with a mass from 1 to 10 times that of our planet. One of these newly-discovered planets, HD 85512 b, is estimated to be only three-and-a-half times the mass of the Earth and it seems like it is located at the edge of the habitable zone, the orbital belt around a star where water can exist in liquid form.  This is only the second exoplanet discovered within the habitable zone, the first being Gliese 581 d.  Interestingly HARPS has disproved the existence of Gliese 581 g (which I wrote about last year) as a mathematical phantasm–so um, you might want to take that post with a grain of salt. The planet HD 85512 b orbits a star which is is approximately 35 light years from Earth.

In the eight years since the program has started, HARPS has discovered more than 150 exoplanets. HARPS discovers new planets by means of a mind-boggling technology: a spectrograph of stupendous precision is mounted on a 3.6 meter telescope in order to take painstaking observations of numerous nearby stars over a prolonged period of time.  A computer program then compares the tiny variances in the light emitted by these stars.  Stars with planets orbiting them undergo slight changes of radial velocity as the planets’ gravity tugs lightly at the stellar bodies. These shifts can be measured via Doppler shift and compared against the expected spectrographic signature caused by the stars relative drift toward or away from the observatory. Over many years the computer can thereby model the mass and approximate orbit of planets around stars (considering the math and the precise observations required for such calculations makes my hair stand on end).

Kepler, the NASA exoplanet discovery project uses an entirely different technology which involves measuring changes in brightness caused by the transit of a planet across a star’s glowing face.

Today scientists announced the discovery of the exoplanet Gliese 581 g which lies 20.3 light years away from Earth in the planetary system of the red dwarf star Gliese 581 (a star with one third the mass of our sun).   The planet has three times the mass of Earth and is almost certainly tidally locked to its star (in the same fashion that the moon always presents the same face to earth).  It revolves much more closely around its dim little star than our planet does around our sun: the yearly orbit of Gliese 581 g is just 37 of our earth days.  With four known planets, the star Gliese 581 had already featured the largest known planetary system outside of our own (before two more worlds were added to the system in today’s announcement). When exoplanet Gliese 581 d was discovered in 2007, it was regarded as the most earthlike exoplanet and scientists speculated about its potential for harboring life (though Gliese 581 d is now regarded as too cold to have liquid water).  Oh, the discovery of Gliese 581 f was also announced today–but nobody cares since it is located far outside what scientists regard as the habitable zone.

The Red Dwarf Gliese 581 in the Night Sky.

The planet was discovered by the Lick-Carnegie Exoplanet Survey headed up by Dr. Steven Vogt.  The team has taken to calling it “Zarmina” after Steven Vogt’s wife, which I think this is a very beautiful name for a world.  I’m also moved by the fact that Dr. Vogt’s first impulse would be to name the world after his spouse (and I also like the fact that she has a Pashtun name).  Unfortunately we’ll probably get stuck with something less euphonious—probably “Gliese 581 g”.  I guess our astronomical naming conventions confer mixed blessings—I’m still happy we don’t call Uranus “Georgium Sidus” like Sir William Herschel desired.

Speaking of Herschel and planetary discovery, I was pleased to see that Vogt continued Sir William’s glorious tradition of exuberant speculation about extraterrestrial life. At this morning’s press conference, Vogt boldly asserted that “my own personal feeling is that the chances of life on this planet are 100 percent.”  He then spoke about the possibilities of polar bear like life-forms living on the planet’s cold night side, thermophilic life-forms on the hot half, and temperate life forms living on the twilight ring dividing the two extremes.

Tell us more about the nocturnal space yetis!

As with most science news, the planet’s discovery hasn’t produced a huge splash in the media (the discovery of the most earthlike planet so far known was greatly overshadowed by Tony Curtis’ death).  The few short mainstream news article to mention this discovery were striking to me for their comments sections.  Although many people leaving comments were filled with wonder and curiosity, a distressing number seemed very ignorant of basic scientific principles (or basic principles of anything).  A shocking number of commenters wanted to send all Republicans to Gliese 581g (an equal number wished to send all Democrats instead).  What happened in or national discourse that a citizen’s first reaction to hearing about a new planet is to banish his political foes there?  When did the United States become Renaissance Florence? Other people demanded that we not exploit the newly discovered planet’s resources but instead concentrate on solving our problems here on earth (20.3 light years might seem like a tiny number but it converts to 1.92048727 × 1017 meters).  We probably have better sources of bauxite and blood diamonds! In a similar vein, quite a few folks demanded that we stop studying the heavens altogether and provide them with cushy jobs, new sofas, and tv dinners.  In short, the comments made me sad and frustrated.

Gliesian scientists have reluctantly concluded that Earth is only inhabited by internet trolls and primitive one-party life forms.

Corot and Kepler, the two big missions for spotting earthlike worlds (from the French and NASA respectively), are only just beginning to yield discoveries, so I expect we will be hearing about a lot of earth-like worlds.  Let’s hope humankind grows technologically, socially, and politically as the new planets are tabulated!

[Also, rest in Peace Tony Curtis, I loved you in “The Great Race” when I was 6.]

Ye Olde Ferrebeekeeper Archives

October 2020
M T W T F S S
 1234
567891011
12131415161718
19202122232425
262728293031