Space art: PlanetQuest Exoplanet Travel Posters

NASA’s PlanetQuest website, which provides info on the search for earth-like exoplanets, now offers beautiful posters in the Exoplanet Travel Series.  The set currently includes posters for three distant planets of particular interest:

Kepler-186f_39x27[1]

 

Kepler-186f is the first Earth-size planet discovered in the potentially ‘habitable zone’ around another star, where liquid water could exist on the planet’s surface. Its star is much cooler and redder than our Sun. If plant life does exist on a planet like Kepler-186f, its photosynthesis could have been influenced by the star’s red-wavelength photons, making for a color palette that’s very different than the greens on Earth. This discovery was made by Kepler, NASA’s planet hunting telescope.

HD_40307g_20x30[1]

 

Twice as big in volume as the Earth, HD 40307g straddles the line between “Super-Earth” and “mini-Neptune” and scientists aren’t sure if it has a rocky surface or one that’s buried beneath thick layers of gas and ice. One thing is certain though: at eight time the Earth’s mass, its gravitational pull is much, much stronger.

Kepler-16b_20x-30[1]

 

Like Luke Skywalker’s planet “Tatooine” in Star Wars, Kepler-16b orbits a pair of stars. Depicted here as a terrestrial planet, Kepler-16b might also be a gas giant like Saturn. Prospects for life on this unusual world aren’t good, as it has a temperature similar to that of dry ice. But the discovery indicates that the movie’s iconic double-sunset is anything but science fiction.

Low cost exoplanet hunting and gathering

A number of projects are showing that finding and studying exoplanets can be done with relatively low cost systems:   : Brave new world-hunters spot exoplanets on the cheap – New Scientist.

Such systems do not replace the space-based observatories like Kepler or the ground-based work by giant telescopes. These systems can look at thousands of stars with high resolution and sensitivity. Instead, the small guys can focus for long periods on just a handful of star systems. This can be done to hunt for new exoplanets or to gather more information on those found by the big systems.

Since Kepler’s staggering number of finds implied most stars probably have planets, astronomers are increasingly aiming for detailed planet studies instead of just making discoveries, Johnson says.

“This is no longer the day of swashbuckling scientists trying to get as many kills as possible,” [Greg Laughlin, an astronomer at the University of California at Santa Cruz,] says. “There is so much great science just sitting on the floor… with the Kepler statistics in hand, we’re no longer in the area of planet hunting. We’re in the era of planet gathering.”

For example, there is the Minerva exoplanet observatory, which describes itself as follows –

Minerva will be an array of small-aperture robotic telescopes outfitted for both photometry and high-resolution spectroscopy. It will be the first U.S. observatory dedicated to exoplanetary science capable of both precise radial velocimetry and transit studies. The multi-telescope concept will be implemented to either observe separate targets or a single target with a larger effective aperture. The flexibility of the observatory will maximize scientific potential and also provide ample opportunities for education and public outreach. The design and implementation of Minerva will be carried out by postdoctoral and student researchers at Caltech.

The primary science goal of Minerva is to discover Earth-like planets in close-in (less than 50-day) orbits around nearby stars, and super-Earths (3-15 times the mass of Earth) in the habitable zones of the closest Sun-like stars. The secondary goal will be to look for transits (eclipses) of known and newly-discovered extrasolar planets, which provide information about the radii and interior structures of the planets….

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Aqawan 1 and Telescope 1 at the Caltech
commissioning site. Image credit: M. Wong

Such a system is even accessible for (wealthy) amateurs. From the NS article:

Minerva uses four 0.7-metre-wide, 2.5-metre-tall commercial telescopes built by a company called PlaneWave, which also sells them to hobbyists for about $200,000 – Amazon founder Jeff Bezos bought one just before Minerva’s team.

The Mearth Project is another exoplanet observatory using arrays of off-the-shelf telescopes.

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There is also the HATNet Exoplanet Survey (Hungarian-made Automated Telescope Network) project.

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HATNet telescopes located at the Fred Lawrence Whipple Observatory (FLWO)
on Mount Hopkins in Arizona, USA (5 telescopes),

 

Volunteer ‘Disk Detectives’ classify over a million possible planetary habitats

A citizen-science project with NASA’s WISE (Wide-field Infrared Survey) mission has been a quite successful:

Volunteer ‘Disk Detectives’ Top 1 Million Classifications
of Possible Planetary Habitats

A NASA-sponsored website designed to crowdsource analysis of data from the agency’s Wide-field Infrared Survey Explorer (WISE) mission has reached an impressive milestone. In less than a year, citizen scientists using DiskDetective.org have logged 1 million classifications of potential debris disks and disks surrounding young stellar objects (YSO). This data will help provide a crucial set of targets for future planet-hunting missions.

Volunteers using DiskDetective.org, a NASA-sponsored citizen science website to find potential planetary nurseries, have made 1 million classifications in less than a year. Goddard astrophysicist Marc Kuchner, the project’s principal investigator, explains how it works. Image Credit: NASA’s Goddard Space Flight Center/S. Wiessinger.
Download this video in HD formats from NASA Goddard’s Scientific Visualization Studio

“This is absolutely mind-boggling,” said Marc Kuchner, an astrophysicist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and the project’s principal investigator. “We’ve already broken new ground with the data, and we are hugely grateful to everyone who has contributed to Disk Detective so far.”

Combing through objects identified by WISE during its infrared survey of the entire sky, Disk Detective aims to find two types of developing planetary environments. The first, known as a YSO disk, typically is less than 5 million years old, contains large quantities of gas, and often is found in or near young star clusters. The second planetary habitat, known as a debris disk, tends to be older than 5 million years, holds little or no gas, and possesses belts of rocky or icy debris that resemble the asteroid and Kuiper belts found in our own solar system. Vega and Fomalhaut, two of the brightest stars in the sky, host debris disks.

Planets form and grow within disks of gas, dust and icy grains surrounding young stars. The particles absorb the star’s light and reradiate it as heat, which makes the stars brighter at infrared wavelengths — in this case, 22 microns — than they would be without a disk.

Computer searches already have identified some objects seen by the WISE survey as potential dust-rich disks. But software can’t distinguish them from other infrared-bright sources, such as galaxies, interstellar dust clouds and asteroids. There may be thousands of potential planetary systems in the WISE data, but the only way to know for sure is to inspect each source by eye.

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The marked asymmetry of the debris disk around the star HD 181327 (shown here in a Hubble image) suggests it may have formed as a result of the collision of two small bodies. Disk Detective aims to discover many other stellar disks using volunteer classifications of data from NASA’s WISE mission. Image Credit: NASA, ESA, G. Schneider (U. of Arizona), HST/GO 12228 Team

Kuchner recognized that searching the WISE database for dusty disks was a perfect opportunity for crowdsourcing. He worked with NASA to team up with the Zooniverse, a collaboration of scientists, software developers and educators who collectively develop and manage citizen science projects on the Internet.

At DiskDetective.org, volunteers watch a 10-second “flip book” of a disk candidate shown at several different wavelengths as observed from three different telescopes, including WISE. They then click one or more buttons that best describe the object’s appearance. Each classification helps astronomers decide which images may be contaminated by background galaxies, interstellar matter or image artifacts, and which may be real disks that should be studied in more detail.

In March 2014, just two months after Disk Detective launched, Kuchner was amazed to find just how invested in the project some users had become. Volunteers complained about seeing the same object over and over. “We thought at first it was a bug in the system,” Kuchner explained, “but it turned out they were seeing repeats because they had already classified every single object that was online at the time.”

Some 28,000 visitors around the world have participated in the project to date. What’s more, volunteers have translated the site into eight foreign languages, including Romanian, Mandarin and Bahasa, and have produced their own video tutorials on using it.

Many of the project’s most active volunteers are now joining in science team discussions, and the researchers encourage all users who have performed more than 300 classifications to contact them and take part.

One of these volunteers is Tadeáš Černohous, a postgraduate student in geodesy and cartography at Brno University of Technology in the Czech Republic. “I barely understood what scientists were looking for when I started participating in Disk Detective, but over the past year I have developed a basic sense of which stars are worthy of further exploration,” he said.

Alissa Bans, a postdoctoral fellow at Adler Planetarium in Chicago and a member of the Disk Detective science team, recalls mentioning that she was searching for candidate YSOs and presented examples of what they might look like on Disk Detective. “In less than 24 hours,” she said, “Tadeáš had compiled a list of nearly 100 objects he thought could be YSOs, and he even included notes on each one.”

Speaking at a press conference at the American Astronomical Society meeting in Seattle on Tuesday, Kuchner said the project has so far netted 478 objects of interest, which the team is investigating with a variety of ground-based telescopes in Arizona, California, New Mexico, Argentina and Chile. “We now have at least 37 solid new disk candidates, and we haven’t even looked at all the new telescope data yet,” he said.

Disk Detective currently includes about 278,000 WISE sources. The team expects to wrap up the current project sometime in 2018, with a total of about 3 million classifications and perhaps 1,000 disk candidates. The researchers then plan to add an additional 140,000 targets to the site.

“We’ve come a long way, but there’s still lots and lots more work to do — so please drop by the site and do a little science with us!” added Kuchner.

387827main_wise20090018-full[1]WISE observatory

WISE has made infrared measurements of more than 745 million objects, compiling the most comprehensive survey of the sky at mid-infrared wavelengths currently available. With its primary mission complete, the satellite was placed in hibernation in 2011. WISE was awoken in September 2013, renamed the Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE), and given a new mission to assist NASA’s efforts in identifying the population of potentially hazardous near-Earth objects (NEOs).

Facilities involved in follow-up studies of objects found with Disk Detective include Apache Point Observatory in Sunspot, New Mexico; Palomar Observatory on Palomar Mountain, California; the Fred Lawrence Whipple Observatory on Mount Hopkins, Arizona; the Leoncito Astronomical Complex in El Leoncito National Park, Argentina; and Las Campanas Observatory, located in the Atacama Desert of Chile.

NASA is exploring our solar system and beyond to understand the universe and our place in it. We seek to unravel the secrets of our universe, its origins and evolution, and search for life among the stars. Today’s announcement shares the discovery of our ever-changing cosmos, and brings us closer to learning whether we are alone in the universe.

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ESO: Dark nebula cloaks new stars in formation

The latest news from the European Southern Observatory (ESO):

Where Did All the Stars Go?
Dark cloud obscures hundreds of background stars

7 January 2015: Some of the stars appear to be missing in this intriguing new ESO image. But the black gap in this glitteringly beautiful starfield is not really a gap, but rather a region of space clogged with gas and dust. This dark cloud is called LDN 483 — for Lynds Dark Nebula 483. Such clouds are the birthplaces of future stars. The Wide Field Imager, an instrument mounted on the MPG/ESO 2.2-metre telescope at ESO’s La Silla Observatory in Chile, captured this image of LDN 483 and its surroundings.

Wide-field view of the sky around the dark nebula LDN 483

This visible-light wide-field image of the region around the dark nebula
LDN 483 was created from photographs forming part of the
Digitized Sky Survey 2. LDN 483 appears at the centre.
Credit: ESO and Digitized Sky Survey 2

LDN 483 [1] is located about 700 light-years away in the constellation of Serpens (The Serpent). The cloud contains enough dusty material to completely block the visible light from background stars. Particularly dense molecular clouds, like LDN 483, qualify as dark nebulae because of this obscuring property. The starless nature of LDN 483 and its ilk would suggest that they are sites where stars cannot take root and grow. But in fact the opposite is true: dark nebulae offer the most fertile environments for eventual star formation.

Astronomers studying star formation in LDN 483 have discovered some of the youngest observable kinds of baby stars buried in LDN 483’s shrouded interior. These gestating stars can be thought of as still being in the womb, having not yet been born as complete, albeit immature, stars.

In this first stage of stellar development, the star-to-be is just a ball of gas and dust contracting under the force of gravity within the surrounding molecular cloud. The protostar is still quite cool — about –250 degrees Celsius — and shines only in long-wavelength submillimetre light [2]. Yet temperature and pressure are beginning to increase in the fledgling star’s core.

This earliest period of star growth lasts a mere thousands of years, an astonishingly short amount of time in astronomical terms, given that stars typically live for millions or billions of years. In the following stages, over the course of several million years, the protostar will grow warmer and denser. Its emission will increase in energy along the way, graduating from mainly cold, far-infrared light to near-infrared and finally to visible light. The once-dim protostar will have then become a fully luminous star.

As more and more stars emerge from the inky depths of LDN 483, the dark nebula will disperse further and lose its opacity. The missing background stars that are currently hidden will then come into view — but only after the passage of millions of years, and they will be outshone by the bright young-born stars in the cloud [3].

This video gives a close-up view of an image of the dark nebula LDN 483 as seen with the Wide Field Imager (WFI) on the MPG/ESO 2.2-metre telescope at the La Silla Observatory. The object is a region of space clogged with gas and dust. These materials are dense enough to effectively eclipse the light of background stars.  Credit: ESO. Music: movetwo