As Kepler continues to gather data, Scientists might need help to keep up. As we build more planet-hunting telescopes to gather even more data, but if we don’t have a system to collectively process the data (via distributed processing), a possible era may occur in which planets will be “discovered” or mined from archived data.
Without the help from Citizen Science, planetary discoveries may come in trickles via data mining by scientists. | We are continously building instruments to gather more and more exoplanet data but we are not preparing the infrastructure to handle the imminent data explosion in Exoplanetary Science. |
| I anticipate a bottleneck when all these planet-hunting telescopes finally get deployed and the copious amounts of data comes flooding in. On what basis am i saying this? Well, take this for example: Dozens of Earth-mass planets could already be within the database of the Kepler Team right now even as we sit waiting for their announcement. That is why i think that not just one earth-sized planets would be announced at one time, but several of them. It’s just that the Kepler scientists are extra careful about their greatest discovery ever in humanity’s history. They are simply making sure that their discoveries are solid before they reveal it to the whole world. |
| The raw data will eventually be shared to the public for Citizen Scientists to gobble up. But I can’t help but think that in some way, it’s a mini-bottleneck. And looking ahead, there is no infrastructure for outside help to “harvest” planets from the raw data the will eventually pour in. |
| How will Scientists keep up with petabytes of raw data? How will web technology keep up? How will the internet enable Citizens to contribute to science for the love of it? |
| Looking around at the changing face of Science that results from the enabling power of web technology, we see the important contributions of a swarm of minds working together for Scientific goals. |
Take a look at GalaxyZoo, FoldIt, StarDust@Home, Rosetta@Home, Einstein@Home and SETI@Home. These are awesome computational engines that tap the human potential in analyzing massive amounts of data, to produce novel scientific discoveries. Despite the public excitement in the field of exoplanets, I’m surprised that there is no program like them that are focused on exoplanetary science. I have reason to think that in some way, the same idea of “distributed processing” can be applied to the deluge of exoplanet data that will arrive in the coming decades.
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| It’s been said that we are currently in the Golden Age of planetary discovery. But if we don’t begin to create some way to collectively “process” the huge amount of data gathered by planet-hunting telescopes, a “bottleneck era” might follow. It will be an era in which we are virtually “aware” that planets lie hidden within massive amounts of data stored somewhere in hard drives locked away at some facility. And like the exoplanet that was re-discovered within the Hubble archives, it would take years to mine these planets |
| I am guessing that that such an era may likely occur if we don’t build a system to process the data in a collective fashion. But then we would refuse to call it a bottleneck era. We would simply name it a much better-sounding term, The Data Mining Age of Exoplanetary Science.Read more at exoplanetology.blogspot.com |
So many planet-hunting telescopes, each with their own specific mission, functionality, method, and cost. WFIRST is a wide-area survey mission. JWST has a bigger mirror and tremendous sensitivity but absolutely tiny (arcmins) sized field of view – thus it is not efficient as a survey instrument. WFIRST will be designed to map out 1000′s of square degrees, e.g. a good fraction of the sky, to magnitudes faint enough to image many millions of galaxies, and use their shapes to study Dark Energy. For some fraction of the time, when not busy with Dark Energy science, it will stare at dense stellar fields where stars frequently pass in front of each other (well… one in a million!) and study the resulting “microlensing” event for signatures of planets orbiting the foreground (lensing) star. By this means it will accumulate a statistical sample of planet detections. However, these will not be planets that we will be able to study in detail. |
You can think of WISE as like the all-sky survey version of Spitzer – longer-wavelength IR/MIR, small aperture, tuned for survey work rather than deep imaging. Due to need of cryogen, the mission will not last much more than a year. |
WFIRST is different in almost every way from WISE. They are both survey missions but WISE surveys in a “scanning” mode while WFIRST will point and shoot. WFIRST is shorter-wavelength, larger aperture, larger field of view. WISE is four-band photometry, WFIRST is (not sure but…) some mix of deep photometry and multiobject spectroscopy. WISE is targeting bright cool (mainly Galactic) objects over the whole sky, WFIRST is targeting faint galaxies and supernovae over 20,000 square degrees (plus the microlensing angle). One of the main challenges / cost drivers for WFIRST will be sending all of its data back to Earth – this will be a hugely data-intensive mission, probably the largest data-volume science mission ever (assuming it succeeds). WISE data requirements are relatively modest. |
WFIRST’s goals can also be distinguished from those of Kepler, assuming the planet-search part of the WFIRST program is carried out. Kepler is looking for transits in a single targeted field. It has found hundreds of these and that will certainly help in characterizing exoplanet demographics. However, searching for transits restricts your sensitivity to planets close to their parent star – roughly as close as Earth (1 A.U.) or closer. WFIRST will be sensitive to planets across a much broader range of orbital distances, and down to smaller masses than Kepler. However, it will not be possible to “follow up” WFIRST-discovered planets the way astronomers are doing now with Kepler discoveries. So for WFIRST “what you see is what you get” whereas astronomers are hoping that the Kepler planets develop into a whole cottage industry of their own, with people continuing to study them intensively long after the Kepler mission is over. Read more at sdunnebacke.wordpress.com |
Timothy Ferris reflects on the ongoing saga of exoplanet discoveries. It took humans thousands of years to explore our own planet and centuries to comprehend our neighboring planets, but nowadays new worlds are being discovered every week. To date, astronomers have identified more than 370 “exoplanets,” worlds orbiting stars other than the sun. Many are so strange
as to confirm the biologist J. B. S. Haldane’s famous remark that “the universe is not only queerer than we suppose, but queerer than we can suppose.” There’s an Icarus-like “hot Saturn” 260 light-years from Earth, whirling around
its parent star so rapidly that a year there lasts less than three days. Circling another star 150 light-years out is a scorched “hot Jupiter,” whose
upper atmosphere is being blasted off to form a gigantic, comet-like tail. Three benighted planets have been found orbiting a pulsar—the remains of a once mighty star shrunk into a spinning atomic nucleus the size of a city—while untold numbers of worlds have evidently fallen into their suns or been flung out of their systems to become “floaters” that wander in eternal darkness. |
Amid such exotica, scientists are eager for a hint of the familiar: planets resembling Earth, orbiting their stars at just the right distance—neither too hot nor too cold—to support life as we know it. No planets quite like our own have yet been found, presumably because they’re inconspicuous. To see a planet as small and dim as ours amid the glare of its star is like trying to see a firefly in a fireworks display; to detect its gravitational influence on the star is like listening for a cricket in a tornado. Yet by pushing technology to the limits, astronomers are rapidly approaching the day when they can find another Earth and interrogate it for signs of life. Read more at ngm.nationalgeographic.com |
Transit-Timing Variation (TTV) of WASP-3b hints at another planet in resonant 2:1 orbit, but not an exomoon. | We found that the configuration with the hypothetical
second planet of the mass of about 15 Earth masses, located close to the outer
2:1 mean motion resonance is the most likely scenario reproducing observed
transit timing. Read more at arxiv.org |
Based on this study which incorporated 3 components in the model: gas, planetesimals and dust–its says that in binary systems such as Alpha Centauri– kilometer-sized planetesimals can be formed, and can still grow even in unfavorable conditions. The largest objects formed inside 1.4 AU with significant growth inside the Habitable Zone.
Abstract: We study the collisional evolution of km-sized planetesimals in tight binary
star systems to investigate whether accretion towards protoplanets can proceed
despite the strong gravitational perturbations from the secondary star. The
orbits of planetesimals are numerically integrated in two dimensions under the
influence of the two stars and gas drag. The masses and orbits of the
planetesimals are allowed to evolve due to collisions with other planetesimals
and accretion of collisional debris. In addition, the mass in debris can evolve
due to planetesimal-planetesimal collisions and the creation of new
planetesimals. We show that it is possible in principle for km-sized
planetesimals to grow by two orders of magnitude in size if the efficiency of
planetesimal formation is relatively low. We discuss the limitations of our
two-dimensional approach.
Read more at arxiv.org |
The science behind detecting exoplanets via transit method.
Abstract: When we are fortunate enough to view an exoplanetary system nearly edge-on,
the star and planet periodically eclipse each other. Observations of eclipses
(transits and occultations) provide a bonanza of information that cannot be
obtained from radial-velocity data alone, such as the relative dimensions of
the planet and its host star, as well as the orientation of the planet’s orbit
relative to the sky plane and relative to the stellar rotation axis. The
wavelength-dependence of the eclipse signal gives clues about the the
temperature and composition of the planetary atmosphere. Anomalies in the
timing or other properties of the eclipses may betray the presence of
additional planets or moons. Searching for eclipses is also a productive means
of discovering new planets. This chapter reviews the basic geometry and physics
of eclipses, and summarizes the knowledge that has been gained through eclipse
observations, as well as the information that might be gained in the future.
Read more at arxiv.org |
To overcome the blinding glare of stars in finding exoplanets (Moth-Searchlight analogy), 2 techniques are used: Angular Differential Imaging (ADI) & Spectral Differential Imaging (SDI) “Now in order to determine if a blob in the structure surrounding the star, is actually a planet or not, there are two different techniques which are currently used. These are known as Angular Differential imaging or ADI, and Spectral Differential imaging, SDI. |
Spectral Differential Imaging, your taking two simultaneous images of the star in two slightly different spectral bands. What happens, is that the instrumental response, changes slightly; and it changes at a spatial scale; an instrumental artifact, will appear to shift, or change its radial distance from the parent star. By comparison an astronomical source will always remain at the same fixed distance from the central star. Therefore we can distinguish between an instrumental source and an astronomical source by looking to see if there’s any apparent motion of these faint blobs, between the two wave lengths. Read more at 365daysofastronomy.org |
Careful examination of the Doppler shifts during transits allowed Astronomers to determine the direction of the planet’s orbital motion relative to its parent star’s rotation via the Rossiter–McLaughlin effect . As the main star rotates on its axis, one quadrant of its photosphere will be seen to be coming towards the viewer, and the other quadrant to be moving away. These motions produce blueshifts and redshifts , respectively, in the star’s spectrum, usually observed as a broadening of the spectral lines . When the secondary star or planet transits the primary, it blocks part of the latter’s disc, preventing some of the shifted light from reaching the observer. This causes the observed mean redshift of the primary star as a whole to vary from its normal value. As the transiting object moves across to the other side of the star’s disc, the redshift anomaly will switch from being negative to being positive, or vice versa. The Rossiter–McLaughlin effect is a spectroscopic phenomenon observed when either an eclipsing binary’s secondary star or an extrasolar planet is seen to transit across the face of the primary or parent star. As the main star rotates on its axis, one quadrant of its photosphere will be seen to be coming towards the viewer, and the other quadrant to be moving away. These motions produce blueshifts and redshifts, respectively, in the star’s spectrum, usually observed as a broadening of the spectral lines. When the secondary star or planet transits the primary, it blocks part of the latter’s disc, preventing some of the shifted light from reaching the observer. This causes the observed mean redshift of the primary star as a whole to vary from its normal value. As the transiting object moves across to the other side of the star’s disc, the redshift anomaly will switch from being negative to being positive, or vice versa. Read more at en.wikipedia.org |
To detect the direction of WASP-17b’s orbit: It was first detected through the transit photometry technique by the Wide Area Search for Planets (WASP) consortium of British universities, using the WASP-South camera array in South Africa.
Then to detect its retrograde motion the WASP team needed an assist from planet hunters at the Geneva Observatory, who specialize in radial velocity measurements. WASP-17 was first detected through the transit photometry technique by the Wide Area Search for Planets (WASP) consortium of British universities, using the WASP-South camera array in South Africa. But in order to detect its retrograde motion the WASP team needed an assist from planet hunters at the Geneva Observatory, who specialize in radial velocity measurements. Read more at planetary.org |
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