David Kirkpatrick

July 15, 2010

Is it a planet? Is it a comet? I don’t know!

News from NASA hot from the inbox:

NASA Finds Super Hot Planet With Unique Comet-Like Tail

WASHINGTON, July 15 /PRNewswire-USNewswire/ — Astronomers using NASA’s Hubble Space Telescope have confirmed the existence of a baked object that could be called a “cometary planet.” The gas giant planet, named HD 209458b, is orbiting so close to its star that its heated atmosphere is escaping into space.

Observations taken with Hubble’s Cosmic Origins Spectrograph (COS) suggest powerful stellar winds are sweeping the cast-off atmospheric material behind the scorched planet and shaping it into a comet-like tail.

“Since 2003 scientists have theorized the lost mass is being pushed back into a tail, and they have even calculated what it looks like,” said astronomer Jeffrey Linsky of the University of Colorado in Boulder, leader of the COS study. “We think we have the best observational evidence to support that theory. We have measured gas coming off the planet at specific speeds, some coming toward Earth. The most likely interpretation is that we have measured the velocity of material in a tail.”

The planet, located 153 light years from Earth, weighs slightly less than Jupiter but orbits 100 times closer to its star than the Jovian giant. The roasted planet zips around its star in a short 3.5 days. In contrast, our solar system’s fastest planet, Mercury, orbits the sun in 88 days. The extrasolar planet is one of the most intensely scrutinized, because it is the first of the few known alien worlds that can be seen passing in front of, or transiting, its star. Linsky and his team used COS to analyze the planet’s atmosphere during transiting events.

During a transit, astronomers study the structure and chemical makeup of a planet’s atmosphere by sampling the starlight that passes through it. The dip in starlight because of the planet’s passage, excluding the atmosphere, is very small, only about 1.5 percent. When the atmosphere is added, the dip jumps to 8 percent, indicating a bloated atmosphere.

COS detected the heavy elements carbon and silicon in the planet’s super-hot 2,000 degrees Fahrenheit atmosphere. This detection revealed the parent star is heating the entire atmosphere, dredging up the heavier elements and allowing them to escape the planet.

The COS data also showed the material leaving the planet was not all traveling at the same speed. “We found gas escaping at high velocities, with a large amount of this gas flowing toward us at 22,000 miles per hour,” Linsky said. “This large gas flow is likely gas swept up by the stellar wind to form the comet-like tail trailing the planet.”

Hubble’s newest spectrograph has the ability to probe a planet’s chemistry at ultraviolet wavelengths not accessible to ground-based telescopes. COS is proving to be an important instrument for probing the atmospheres of “hot Jupiters” like HD 209458b.

Another Hubble instrument, the Space Telescope Imaging Spectrograph (STIS), observed the planet in 2003. The STIS data showed an active, evaporating atmosphere, and a comet-tail-like structure was suggested as a possibility. But STIS wasn’t able to obtain the spectroscopic detail necessary to show a tail, or an Earthward-moving component of the gas, during transits. The tail was detected for the first time because of the unique combination of very high ultraviolet sensitivity and good spectral resolution provided by COS.

Although this extreme planet is being roasted by its star, it won’t be destroyed anytime soon. “It will take about a trillion years for the planet to evaporate,” Linsky said.

The results appeared in the July 10 issue of The Astrophysical Journal.

The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA’s Goddard Space Flight Center in Greenbelt, Md., manages the telescope. The Space Telescope Science Institute, operated for NASA by the Association of Universities for Research in Astronomy, Inc. in Washington, conducts Hubble science operations.

For illustrations and more information about HD 209458b, visit:

http://www.nasa.gov/hubble

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PRN Photo Desk photodesk@prnewswire.com
http://photos.prnewswire.com/prnh/20081007/38461LOGO
Source: NASA
Web Site:  http://www.nasa.gov/

October 19, 2009

Pollution and ET

Filed under: et.al., Science, Technology — Tags: , , , , — David Kirkpatrick @ 12:57 pm

Via KurzweilAI.net — An interesting and novel idea on searching for extraterrestrial life.

To spot an alien, follow the pollution trail

New Scientist Space, Oct. 19, 2009

Light pollution from cities and the presence of CFCs and other artificial compounds in the atmosphere (indicated by absorption at characteristic wavelengths) could be signs of intelligent life on alien planets.

Read Original Article>>

September 30, 2009

Raining rocks

Filed under: et.al., Science — Tags: , , , — David Kirkpatrick @ 8:33 pm

The universe is an amazing place even in simulation and informed guesswork. Sounds like this planet requires a ultra-duty umbrella.

From the link:

Not so the atmosphere of COROT-7b, an exoplanet discovered last February by the COROT space telescope launched by the French and European space agencies

According to models by scientists at Washington University in St. Louis, COROT-7b’s atmosphere is made up of the ingredients of rocks and when “a front moves in,” pebbles condense out of the air and rain into lakes of molten lava below.

The work, by Laura Schaefer, research assistant in the Planetary Chemistry Laboratory, and Bruce Fegley Jr., Ph.D., professor of earth and planetary sciences in Arts & Sciences, appears in the Oct. 1 issue of The Astrophysical Journal.

Astronomers have found nearly 400 extra-solar planets, or exoplanets, in the past 20 years. But because of the limitations of the indirect means by which they are discovered, most are Hot Jupiters, chubby gas giants orbiting close to their parent stars. (More than 1,300 Earths could be packed inside Jupiter, which has 300 times the mass of Earth.)

COROT-7b, on the other hand, is less than twice the size of Earth and only five times its mass.

It was the first planet found orbiting the star COROT-7, an orange dwarf in the constellation Monoceros, or the Unicorn. (This priority is designated by the letter b.)

March 7, 2009

Kepler launched

News from NASA.

The release:

NASA’s Kepler Mission Rockets to Space in Search of Other Earths

CAPE CANAVERAL, Fla., March 7 /PRNewswire-USNewswire/ — NASA’s Kepler mission successfully launched into space from Cape Canaveral Air Force Station, Fla., aboard a United Launch Alliance Delta II at 10:49 p.m. EST, Friday. Kepler is designed to find the first Earth-size planets orbiting stars at distances where water could pool on the planet’s surface. Liquid water is believed to be essential for the formation of life.

(Logo: /Photo: http://www.newscom.com/cgi-bin/prnh/20081007/38461LOGO )

“It was a stunning launch,” said Kepler Project Manager James Fanson of NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “Our team is thrilled to be a part of something so meaningful to the human race — Kepler will help us understand if our Earth is unique or if others like it are out there.”

Engineers acquired a signal from Kepler at 12:11 a.m. Saturday, after it separated from its spent third-stage rocket and entered its final sun-centered orbit, trailing 950 miles behind Earth. The spacecraft is generating its own power from its solar panels.

“Kepler now has the perfect place to watch more than 100,000 stars for signs of planets,” said William Borucki, the mission’s science principal investigator at NASA’s Ames Research Center at Moffett Field, Calif. Borucki has worked on the mission for 17 years. “Everyone is very excited as our dream becomes a reality. We are on the verge of learning if other Earths are ubiquitous in the galaxy.”

Engineers have begun to check Kepler to ensure it is working properly, a process called “commissioning” that will take about 60 days. In about a month or less, NASA will send up commands for Kepler to eject its dust cover and make its first measurements. After another month of calibrating Kepler’s single instrument, a wide-field charge-couple device camera, the telescope will begin to search for planets.

The first planets to roll out on the Kepler “assembly line” are expected to be the portly “hot Jupiters” — gas giants that circle close and fast around their stars. NASA’s Hubble and Spitzer space telescopes will be able to follow up with these planets and learn more about their atmospheres. Neptune-size planets will most likely be found next, followed by rocky ones as small as Earth. The true Earth analogs — Earth-sized planets orbiting stars like our sun at distances where surface water, and possibly life, could exist — would take at least three years to discover and confirm. Ground-based telescopes also will contribute to the mission by verifying some of the finds.

In the end, Kepler will give us our first look at the frequency of Earth-size planets in our Milky Way galaxy, as well as the frequency of Earth-size planets that could theoretically be habitable.

“Even if we find no planets like Earth, that by itself would be profound. It would indicate that we are probably alone in the galaxy,” said Borucki.

As the mission progresses, Kepler will drift farther and farther behind Earth in its orbit around the sun. NASA’s Spitzer Space Telescope, which was launched into the same orbit more than five years ago, is now more than 62 million miles behind Earth.

Kepler is a NASA Discovery mission. Ames is the home organization of the science principal investigator and is responsible for the ground system development, mission operations and science data analysis. JPL manages the Kepler mission development. Ball Aerospace & Technologies Corp. of Boulder, Colo., is responsible for developing the Kepler flight system and supporting mission operations. NASA’s Launch Services Program at NASA’s Kennedy Space Center, Fla., managed the launch service including payload integration and certifying the Delta II launch vehicle for NASA’s use.

For more information about the Kepler mission, visit:

http://www.nasa.gov/kepler

Photo:  http://www.newscom.com/cgi-bin/prnh/20081007/38461LOGO
AP Archive:  http://photoarchive.ap.org/
PRN Photo Desk photodesk@prnewswire.com
Source: NASA
   

Web Site:  http://www.nasa.gov/

February 15, 2009

Exploring distant planets

I love news like this.

A release from today:

Exploring planets in distant space and deep interiors

Washington, D.C.— In recent years researchers have found hundreds of new planets beyond our solar system, raising questions about the origins and properties of these exotic worlds—not to mention the possible presence of life. Speaking at a symposium titled “The Origin and Evolution of Planets” held at the annual meeting of the American Association for the Advancement of Science, two Carnegie Institution scientists will present their perspectives on the new era of planetary exploration.

Alan Boss of Carnegie’s Department of Terrestrial Magnetism and author of the new book The Crowded Universe: The Search for Living Planets points out that evidence for all three classes of planets known in our Solar System—ice giants, gas giants, and terrestrial (rocky) planets—has been detected in extra-solar systems. “We already know enough now to say that the Universe is probably loaded with terrestrial planets similar to the Earth,” he says. “We should expect that there are going to be many planets which are habitable, so probably some are going to be inhabited as well.”

Boss expects that NASA’s Kepler spacecraft, due to launch in early March and dedicated to searching for Earthlike planets, will put his ideas to the test.

Russell Hemley, director of Carnegie’s Geophysical Laboratory, studies the fundamental physics and chemistry of materials under extreme conditions. Understanding how the chemical building blocks of planets, such as hydrogen, oxygen, silicon, iron, and other crucial elements such as carbon, respond to conditions in the deep interior of planets, where pressures can exceed those on the surface by factors of millions, is key to understanding how planets might form and evolve. High-pressure studies can also offer clues to the search for life on planets different from our own. “Our work is uncovering not only exciting new physics and chemistry, but also new findings in biology that are relevant to the prospects for life in whatever form beyond the Earth,” says Hemley. “Experiments are showing that there is viability of life as we know it now under surprisingly extreme conditions.”

 

###

 

The AAAS symposium “Origin and Evolution of Planets” will be held on Feb. 14, 1:30-4:30 p.m. CST, at the Chicago Hyatt Regency Hotel, Ballroom C. A news briefing preceding the symposium is scheduled for 10:00 a.m. CST at the Hyatt Regency Hotel, Ballroom D. For more information on this event, contact the AAAS Press Office at 312-239-4811.

The Carnegie Institution (www.CIW.edu) has been a pioneering force in basic scientific research since 1902. It is a private, nonprofit organization with six research departments throughout the U.S. Carnegie scientists are leaders in plant biology, developmental biology, astronomy, materials science, global ecology, and Earth and planetary science.

Update 2/15/09 — Here’s a BBC News story on this release.

November 14, 2008

First images of new multi-planet solar system

The release:

Astronomers capture first images of
newly-discovered solar system

LIVERMORE, Calif. — Astronomers for the first time have taken snapshots of a multi-planet solar system, much like ours, orbiting another star.

The new solar system orbits a dusty young star named HR8799, which is 140 light years away and about 1.5 times the size of our sun. Three planets, roughly 10, 10 and 7 times the mass of Jupiter, orbit the star. The size of the planets decreases with distance from the parent star, much like the giant planets do in our system.

And there may be more planets out there, but scientists say they just haven’t seen them yet.

“Every extrasolar planet detected so far has been a wobble on a graph. These are the first pictures of an entire system,” said Bruce Macintosh, an astrophysicist from Lawrence Livermore National Laboratory and one of the key authors of a paper appearing in the Nov. 13 issue of Science Express.We’ve been trying image planets for eight years with no luck and now we have pictures of three planets at once.”

Using high-contrast, near-infrared adaptive optics observations with the Keck and Gemini telescopes, the team of researchers from Livermore, the NRC Herzberg Institute of Astrophysics in Canada, Lowell Observatory, University of California Los Angeles, and several other institutions were able to see three orbiting planetary companions to HR8799.

Astronomers have known for a decade through indirect techniques that the sun was not the only star with orbiting planets.

“But we finally have an actual image of an entire system,” Macintosh said. “This is a milestone in the search and characterization of planetary systems around stars.”

During the past 10 years, various planet detection techniques have been used to find more than 200 exoplanets. But these methods all have limitations. Most infer the existence of a planet through its influence on the star that it orbits, but don’t actually tell scientists anything about the planet other than its mass and orbit. Second, the techniques are all limited to small to moderate planet-star separation, usually less than about 5 astronomical units (one AU is the average distance from the sun to Earth).

In the new findings, the planets are 24, 37 and 67 times the Earth-sun separation from the host star. The furthest planet in the new system orbits just inside a disk of dusty debris, similar to that produced by the comets of the Kuiper belt of our solar system (just beyond the orbit of Neptune at 30 times Earth-sun distance).

“HR8799’s dust disk stands out as one of the most massive in orbit around any star within 300 light years of Earth” said UCLA’s Ben Zuckerman.

In some ways, this planetary system seems to be a scaled-up version of our solar system orbiting a larger and brighter star, Macintosch said.

The host star is known as a bright, blue A-type star. These types of stars are usually ignored in ground and space-based direct imaging surveys since they offer a less favorable contrast between a bright star and a faint planet. But they do have an advantage over our sun: Early in their life, they can retain heavy disks of planet-making material and therefore form more massive planets at wider separations that are easier to detect. In the recent study, the star also is young – less than 100 million years old – which means its planets are still glowing with heat from their formation.

“Seeing these planets directly – separating their light from the star – lets us study them as individuals, and use spectroscopy to study their properties, like temperature or composition,” Macintosh said.

“Detailed comparison with theoretical model atmospheres confirms that all three planets possess complex atmospheres with dusty clouds partially trapping and re-radiating the escaping heat” said Lowell Observatory astronomer Travis Barman.

The planets have been extensively studied using adaptive optics on the giant Keck and Gemini telescopes on Mauna Kea, Hawaii. Adaptive optics enables astronomers to minimize the blurring effects of the Earth’s atmosphere, producing images with unprecedented detail and resolution. LLNL helped build the original adaptive optics system for Keck, the world’s largest optical telescope. Christian Marois, a former LLNL postdoctoral researcher and the primary author of the paper who now works at NRC, developed an advanced computer processing technique that helps to extract the planets from the vastly brighter light of the star.

A team led by Macintosh is constructing a much more advanced adaptive optics system designed from the beginning to block the light of bright stars and reveal even fainter planets. Known as the Gemini Planet Imager (http://gpi.berkeley.edu), this new system will be up to 100 times more sensitive than current instruments and able to image planets similar to our own Jupiter around nearby stars.

“I think there’s a very high probability that there are more planets in the system that we can’t detect yet,” Macintosh said. “One of the things that distinguishes this system from most of the extrasolar planets that are already known is that HR8799 has its giant planets in the outer parts – like our solar system does – and so has ‘room’ for smaller terrestrial planets – far beyond our current ability to see – in the inner parts.”

Founded in 1952, Lawrence Livermore National Laboratory is a national security laboratory, with a mission to ensure national security and apply science and technology to the important issues of our time. Lawrence Livermore National Laboratory is managed by Lawrence Livermore National Security, LLC for the U.S. Department of Energy’s National Nuclear Security Administration.

Near-infrared false-color image taken with the W.M. Keck II telescope and adaptive optics. The three planets are labelled b, c, and d. The colored speckles in the center are the remains of the bright light from their parent star after image processing.

Near-infrared false-color image taken with the W.M. Keck II telescope and adaptive optics. The three planets are labelled b, c, and d. The colored speckles in the center are the remains of the bright light from their parent star after image processing.

October 10, 2008

Extrasolar planets and dust rings

An interesting press release from NASA today:

NASA Supercomputer Shows How Dust Rings Point to Exo-Earths

GREENBELT, Md., Oct. 10 /PRNewswire-USNewswire/ — Supercomputer simulations of dusty disks around sunlike stars show that planets nearly as small as Mars can create patterns that future telescopes may be able to detect. The research points to a new avenue in the search for habitable planets.

(Logo:  http://www.newscom.com/cgi-bin/prnh/20081007/38461LOGO )

“It may be a while before we can directly image earthlike planets around other stars but, before then, we’ll be able to detect the ornate and beautiful rings they carve in interplanetary dust,” says Christopher Stark, the study’s lead researcher at the University of Maryland, College Park.

Working with Marc Kuchner at NASA’s Goddard Space Flight Center in Greenbelt, Md., Stark modeled how 25,000 dust particles responded to the presence of a single planet — ranging from the mass of Mars to five times Earth’s — orbiting a sunlike star. Using NASA’s Thunderhead supercomputer at Goddard, the scientists ran 120 different simulations that varied the size of the dust particles and the planet’s mass and orbital distance.

“Our models use ten times as many particles as previous simulations. This allows us to study the contrast and shapes of ring structures,” Kuchner adds. From this data, the researchers mapped the density, brightness, and heat signature resulting from each set of parameters.

“It isn’t widely appreciated that planetary systems — including our own — contain lots of dust,” Stark adds. “We’re going to put that dust to work for us.”

Much of the dust in our solar system forms inward of Jupiter’s orbit, as comets crumble near the sun and asteroids of all sizes collide. The dust reflects sunlight and sometimes can be seen as a wedge-shaped sky glow — called the zodiacal light — before sunrise or after sunset.

The computer models account for the dust’s response to gravity and other forces, including the star’s light. Starlight exerts a slight drag on small particles that makes them lose orbital energy and drift closer to the star.

“The particles spiral inward and then become temporarily trapped in resonances with the planet,” Kuchner explains. A resonance occurs whenever a particle’s orbital period is a small-number ratio — such as two-thirds or five-sixths — of the planet’s.

For example, if a dust particle makes three orbits around its star every time the planet completes one, the particle repeatedly will feel an extra gravitational tug at the same point in its orbit. For a time, this extra nudge can offset the drag force from starlight and the dust can settle into subtle ring-like structures.

“The particles spiral in toward the star, get trapped in one resonance, fall out of it, spiral in some more, become trapped in another resonance, and so on,” Kuchner says. Accounting for the complex interplay of forces on tens of thousands of particles required the mathematical horsepower of a supercomputer.

Some scientists note that the presence of large amounts of dust could present an obstacle to directly imaging earthlike planets. Future space missions — such as NASA’s James Webb Space Telescope, now under construction and scheduled for launch in 2013, and the proposed Terrestrial Planet Finder — will study nearby stars with dusty disks. The models created by Stark and Kuchner give astronomers a preview of dust structures that signal the presence of otherwise hidden worlds.

“Our catalog will help others infer a planet’s mass and orbital distance, as well as the dominant particle sizes in the rings,” Stark says.

Stark and Kuchner published their results in the October 10 issue of The Astrophysical Journal. Stark has made his atlas of exo-zodiacal dust simulations available online.

  For images related to this release, please visit:

  http://www.nasa.gov/centers/goddard/news/topstory/2008/dust_rings.html

  To explore the Exozodi Simulation Catalog, please visit:

  http://asd.gsfc.nasa.gov/Christopher.Stark/catalog.php

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AP Archive:  http://photoarchive.ap.org/
PRN Photo Desk photodesk@prnewswire.com
Source: NASA
   

Web Site:  http://www.nasa.gov/

September 23, 2008

NASA’s Kepler Spacecraft closer to launch

Filed under: Science — Tags: , , , , — David Kirkpatrick @ 1:34 pm

The spaceship just passed an extreme temperature test.

The release:

NASA’s Kepler Spacecraft Baked and Ready for More Tests

PASADENA, Calif., Sept. 23 /PRNewswire-FirstCall/ — NASA’s planet-hunting Kepler mission, scheduled to launch in 2009, has survived an extreme temperature test.

(Photo: http://www.newscom.com/cgi-bin/prnh/20080923/LATU531)

The thermal vacuum test is part of a series of environmental tests the spacecraft will undergo before it blasts into space aboard a Delta II rocket from the Cape Canaveral Air Force Station, Fla.

“Kepler functioned extremely well at the intense temperatures it will encounter in space,” said James Fanson, Kepler project manager at NASA’s Jet Propulsion Laboratory, Pasadena, Calif.

The test, which was performed at Ball Aerospace & Technologies Corp. in Boulder, Colo., simulates the vacuum of space, and the extreme temperatures Kepler will face once launched. The spacecraft is tucked into a vacuum chamber and surrounded by a cold shroud to mimic the deep chill of space. One side of the spacecraft — the side with solar panels — is then baked as if it were being heated by the sun.

The goal is to make sure that the spacecraft and its detectors operate properly in the space-like environment. An electromagnetic compatibility test, to ensure Kepler’s electronics are sound, will begin soon.

Kepler will monitor 100,000 stars, searching for signs of planets — including ones as small as or smaller than Earth. To date, no Earth-sized planet has been discovered.

“The results of these tests are now being used to prepare for the science operations that will start after the spacecraft launches and undergoes in-orbit checkout,” said Bill Borucki of NASA Ames Research Center, Moffett Field, Calif., the science principal investigator for the Kepler Mission.

Kepler is a NASA Discovery mission. In addition to being the home organization of the science principal investigator, NASA Ames Research Center is responsible for the ground system development, mission operations and science data analysis. Kepler mission development is managed by JPL. Ball Aerospace & Technologies Corp. is responsible for developing the Kepler flight system and supporting mission operations.

More information about the Kepler mission is at http://kepler.nasa.gov/. More information about extrasolar planets and NASA’s planet-finding program is at http://planetquest.jpl.nasa.gov/.

Photo:  NewsCom:  http://www.newscom.com/cgi-bin/prnh/20080923/LATU531
AP Archive:  http://photoarchive.ap.org/
AP PhotoExpress Network:  PRN11
PRN Photo Desk, photodesk@prnewswire.com
Source: Ball Aerospace & Technologies Corp.
   

Web site:  http://www.ballaerospace.com/
http://kepler.nasa.gov/
http://planetquest.jpl.nasa.gov/