Showing posts with label Planets. Show all posts
Showing posts with label Planets. Show all posts
Wednesday, October 14, 2015
Secret Worlds in Our Solar System | VIDEO
Since 1989 astronomers when Voyager 2 flew past Neptune and measured its gravity field, astronomers have known that the blue giant harbors a secret world inside.
Monday, October 05, 2015
Protecting Planets Against An Alien Invasion
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| An adult tardigrade. Photo: Schokraie E, Warnken U, Hotz-Wagenblatt A, Grohme MA, Hengherr S, et al. CC BY 2.5. |
By Brian Koberlein
www.forbes.com
10-4-15
NASA has an Office of Planetary Protection. Its purpose is not to protect Earth from invasion by some green skinned monsters, but rather to protect the rest of the Universe from us. With the recent evidence of liquid water on Mars , the possibility of life on the red planet has become a bit more possible, and protecting potential martians from an alien threat is a real challenge.
While Earth is the only planet for which the presence of life is certain, we know that living things can be extraordinarily hardy. We’ve seen organisms thrive in areas of extreme temperature and acid environments. Tardigrades (also known as water bears) have survived the cold vacuum of space, and bacteria have been found within nuclear waste. So it’s not unreasonable to imagine a terrestrial organism hitching a ride on a spacecraft. If that spacecraft comes into contact with a potentially habitable environment they could become an invasive species on another world. [...]
Tuesday, April 15, 2014
Alien Star Systems Teeming with Planets
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"Getting Closer and Closer" --Kepler Mission Findings Reveal Alien Star Systems in a Milky Way Teeming with Planets
By www.dailygalaxy.com
4-15-14
Five years ago today, on March 6, 2009, NASA's Kepler Space Telescope rocketed into the night skies to find planets around other stars within a field of view 1/400th the size of the Milky Way in search of potentially habitable worlds. Since then, Kepler has unveiled a whole new side of our galaxy -- one that is teeming with planets. Because of Kepler we now know that most stars have planets, Earth-sized planets are common, and planets quite unlike those in our solar system exist.
"This is the biggest haul ever,” says Jason Rowe of the nasa Ames Research Center, who co-led the research. The scientists studied more than 1,200 planetary systems and validated 715 planets. All the new worlds are members of multiplanet systems—stars with more than one orbiting satellite.
The image above is an artist's impression of the Kepler-62 star system as seen from the Earth-like planet "f", which scientists believe could support life. Kepler-62 is a star smaller and dimmer than the Sun about 1,000 light years away in the constellation Lyra. A pair of so-called "super-Earths" have been detected within the "habitable zone" of the star, which is around two billion years older than the Sun, raising the possibility of intelligent life more advanced than it is on Earth.
Although no-one knows what the planets are made of, they are believed to be rocky. One, Kepler-62f, is thought to have a radius about 1.4 times greater than the Earth's. The other, Kepler-62e, is estimated to be 1.6 times larger.
This past December 2013, a team of European astrophysicists discovered the most extensive planetary system to date, orbiting star KOI-351. The star system has seven planets, more than in other known planetary systems arranged in a similar fashion to the eight planets in the Solar System, with small rocky planets close to the parent star and gas giant planets at greater distances. . . .
Friday, January 03, 2014
Alien Clouds Blanket Nearby 'Super-Earth' Exoplanet | VIDEO
One of the best-studied nearby extrasolar planets — a body just a little larger than Earth — is swaddled in alien clouds, researchers have found. It is the smallest and most Earth-like world yet to yield the secrets of its atmosphere. Another study has found tantalizing hints of clouds on a larger, Neptune-sized world. The pair of discoveries, reported in Nature, suggests that clouds may envelop many exoplanets.
“We always knew the clouds must be there for some planets, but now we have a wave of results telling us that clouds are actually very common,” says Heather Knutson, a planetary astronomer at the California Institute of Technology in Pasadena and lead author of the second paper.
The two planets are among the closest to our Solar System to have been found so far. The super-Earth discovery involves GJ 1214b, just 13 parsecs (about 42 light years) from us, which whirls around a red dwarf star once every 38 hours. As the planet passes across the star’s face, some of the starlight should filter through the planet's atmosphere, revealing its composition. . . .
Tuesday, December 03, 2013
Great Red Spot On Jupiter, Mystery Finally Solved? | VIDEO
The mystery of why Jupiter's Great Red Spot did not vanish centuries ago may now be solved, and the findings could help reveal more clues about the vortices in Earth's oceans and the nurseries of stars and planets, researchers say.
The Great Red Spot is the most noticeable feature on Jupiter's surface — a storm about 12,400 miles (20,000 kilometers) long and 7,500 miles (12,000 km) wide, about two to three times larger than Earth. Winds at its oval edges can reach up to 425 mph (680 km/h). This giant storm was first recorded in 1831 but may have first been discovered in 1665.
"Based on current theories, the Great Red Spot should have disappeared after several decades," researcher Pedram Hassanzadeh, a geophysical fluid dynamicist at Harvard University,said in a statement. "Instead, it has been there for hundreds of years."
Vortices like the Great Red Spot can dissipate because of many factors. For instance, waves and turbulence in and around the storm sap its winds of energy. It also loses energy by radiating heat. Moreover, the Great Red Spot rests between two powerful jet streams in Jupiter's atmosphere that flow in opposite directions and may slow down its spinning. . . .
Sunday, April 21, 2013
Has Kepler Found Ideal SETI-target Planets?
Mountain View: NASA's Kepler mission has discovered a new planetary system that is home to five small planets around a slightly smaller star than our Sun. Two of them are super-Earth planets, most likely made of rock or ice mixed with rock, which are located in the habitable zone of their host star. This discovery is providing a target for the SETI search, since if life has thrived on these worlds and reached a point where civilization has developed complex technology, it may be detectable.
When the NASA Kepler mission was launched on March 9, 2007, the Delta II rocket was carrying the hope of a large community of scientists who dedicate their work to studying extra-solar planets, planets in orbit around other stars. The Kepler mission's main scientific objective is exploration of the structure and diversity of planetary systems. It accomplishes this goal by staring almost constantly at a large field composed of about 150,000 stars to detect small dips in brightness due to the transits of a planet.
Kepler has already been a successful NASA mission with the discovery of 2,740 planet candidates with estimated sizes from Mercury to larger than Jupiter. A fifth of these planet candidates are also called "super-Earths", a new class of planets, without analog in our solar system, with a radius between 1.25 to 2 times the radius of our planet.
Sunday, February 24, 2013
Kepler Discovers a System of Tiny Planets | SPACE NEWS
NASA's Kepler mission scientists have discovered a new planetary system that is home to the smallest planet yet found around a star similar to our sun.
The planets are located in a system called Kepler-37, about 210 light-years from Earth in the constellation Lyra.
The smallest planet, Kepler-37b, is slightly larger than our moon, measuring about one-third the size of Earth. It is smaller than Mercury, which made its detection a challenge.
The moon-size planet and its two companion planets were found by scientists with NASA's Kepler mission to find Earth-sized planets in or near the “habitable zone,” the region in a planetary system where liquid water might exist on the surface of an orbiting planet.
However, while the star in Kepler-37 may be similar to our sun, the system appears quite unlike the solar system in which we live.
Astronomers think Kepler-37b does not have an atmosphere and cannot support life as we know it. The tiny planet almost certainly is rocky in composition. Kepler-37c, the closer neighboring planet, is slightly smaller than Venus, measuring almost three-quarters the size of Earth. Kepler-37d, the farther planet, is twice the size of Earth. . . .
The planets are located in a system called Kepler-37, about 210 light-years from Earth in the constellation Lyra.
The smallest planet, Kepler-37b, is slightly larger than our moon, measuring about one-third the size of Earth. It is smaller than Mercury, which made its detection a challenge.
The moon-size planet and its two companion planets were found by scientists with NASA's Kepler mission to find Earth-sized planets in or near the “habitable zone,” the region in a planetary system where liquid water might exist on the surface of an orbiting planet.
However, while the star in Kepler-37 may be similar to our sun, the system appears quite unlike the solar system in which we live.
Astronomers think Kepler-37b does not have an atmosphere and cannot support life as we know it. The tiny planet almost certainly is rocky in composition. Kepler-37c, the closer neighboring planet, is slightly smaller than Venus, measuring almost three-quarters the size of Earth. Kepler-37d, the farther planet, is twice the size of Earth. . . .
Tuesday, January 29, 2013
'Habitable Zone' Redefined for Alien Planets — and Maybe Life | SPACE NEWS
One of the most important characteristics of an alien planet is whether or not it falls into what's called the habitable zone — a Goldilocks-like range of not-too-close, not-too-far distances from the parent star that might allow the planet to host life.
Now scientists have redefined the boundaries of the habitable zone for alien planets, potentially kicking out some exoplanets that were thought to fall within it, and maybe allowing a few that had been excluded to squeeze in.
"This will have a significant impact on the number of exoplanets that are within habitable zone," said research team leader Ravi Kumar Kopparapu of Penn State University.
The habitable zone defines the region where a planet might be able to retain liquid water on its surface. Any closer to the star and water would vaporize away; any farther, and it would freeze to ice. But water in its liquid state is what scientists are after, since that is thought to be a prerequisite for life.
The new definition of the habitable zone is based on updated atmospheric databases called HITRAN (high-resolution transmission molecular absorption) and HITEMP (high-temperature spectroscopic absorption parameters), which give the absorption parameters of water and carbon dioxide — two properties that strongly influence the atmospheres of exoplanets, determining whether those planets could host liquid water. . . .
Now scientists have redefined the boundaries of the habitable zone for alien planets, potentially kicking out some exoplanets that were thought to fall within it, and maybe allowing a few that had been excluded to squeeze in.
"This will have a significant impact on the number of exoplanets that are within habitable zone," said research team leader Ravi Kumar Kopparapu of Penn State University.
The habitable zone defines the region where a planet might be able to retain liquid water on its surface. Any closer to the star and water would vaporize away; any farther, and it would freeze to ice. But water in its liquid state is what scientists are after, since that is thought to be a prerequisite for life.
The new definition of the habitable zone is based on updated atmospheric databases called HITRAN (high-resolution transmission molecular absorption) and HITEMP (high-temperature spectroscopic absorption parameters), which give the absorption parameters of water and carbon dioxide — two properties that strongly influence the atmospheres of exoplanets, determining whether those planets could host liquid water. . . .
Saturday, December 15, 2012
Mysterious Metallic Blobs Help Reveal Planets' Innards
Metallic blobs that rise from Earth's core might help explain the mysterious innards of other planets, new research suggests.
Under the outer crust of the Earth sits the rocky mantle layer and then the planet's metallic, iron-dominated core. Scientists can probe these layers indirectly by measuring how the speed of seismic waves and electrical signals change as they zip through them. Analysis of the lowermost mantle in past studies revealed areas of high electrical conductivity (meaning that electric signals travel very easily) and low seismic velocity, suggesting that iron from the outer core was penetrating the mantle.
However, it remained a mystery as to how iron from the core might extensively chemically interact with the mantle. Known processes for how metal from the core might infiltrate rock in the mantle were either too slow or too small in scale to explain the results that researchers saw.
Now a phenomenon discovered by accident and described in the new study in the Dec. 13 issue of the journal Naturereveals that blobs of iron-rich liquid from the outermost core might have, over the history of the Earth, led to a metal-rich layer up to 60 miles (100 kilometers) thick in the Earth's lower mantle. . . .
Under the outer crust of the Earth sits the rocky mantle layer and then the planet's metallic, iron-dominated core. Scientists can probe these layers indirectly by measuring how the speed of seismic waves and electrical signals change as they zip through them. Analysis of the lowermost mantle in past studies revealed areas of high electrical conductivity (meaning that electric signals travel very easily) and low seismic velocity, suggesting that iron from the outer core was penetrating the mantle.
However, it remained a mystery as to how iron from the core might extensively chemically interact with the mantle. Known processes for how metal from the core might infiltrate rock in the mantle were either too slow or too small in scale to explain the results that researchers saw.
Now a phenomenon discovered by accident and described in the new study in the Dec. 13 issue of the journal Naturereveals that blobs of iron-rich liquid from the outermost core might have, over the history of the Earth, led to a metal-rich layer up to 60 miles (100 kilometers) thick in the Earth's lower mantle. . . .
Thursday, November 15, 2012
Theory of Rogue Planets Finally Verified? | SPACE NEWS | VIDEO
Astronomers have discovered a potential "rogue" alien planet wandering alone just 100 light-years from Earth, suggesting that such starless worlds may be extremely common across the galaxy. The free-floating object, called CFBDSIR2149, is likely a gas giant planet four to seven times more massive than Jupiter, scientists say in a new study unveiled today (Nov. 14). The planet cruises unbound through space relatively close to Earth (in astronomical terms; the Milky Way galaxy is 100,000 light-years wide), perhaps after being booted from its own solar system. "If this little object is a planet that has been ejected from its native system, it conjures up the striking image of orphaned worlds, drifting in the emptiness of space," study leader Philippe Delorme, of the Institute of Planetology and Astrophysics of Grenoble in France, said in a statement. . . .
Tuesday, August 28, 2012
VIDEO | Watch: 2,300 Planets Orbit One Star
To illustrate the horde of alien worlds discovered by NASA's Kepler mission, a new animation crams all of them into one hypothetical solar system.
NASA has been on a roll lately, despite some prominent criticism over the past year. The shuttle era may be over, but NASA still has about 100 active missions on its plate, from science satellites and lunar probes to Mars rovers and deep-space telescopes. Its Kepler telescope, for example, just discovered 41 new alien planets in one fell swoop, raising its total to more than 2,300 suspected planets outside our solar system.
To put that number in perspective, planetary scientist Alex Parker made the following animation of Kepler's top 2,299 planet candidates, all shown together as if they orbited a single star. Each one is drawn to scale, Parker notes on Vimeo, with an accurate radius, orbital period and orbital distance–see above.
Parker, who works at the Harvard-Smithsonian Center for Astrophysics, says he made the video to help people grasp the enormity of Kepler's discoveries. "I wanted to convey the astounding number of planet candidates Kepler has found in a way that would really impact the person watching this video," he says in a statement. . . .
NASA has been on a roll lately, despite some prominent criticism over the past year. The shuttle era may be over, but NASA still has about 100 active missions on its plate, from science satellites and lunar probes to Mars rovers and deep-space telescopes. Its Kepler telescope, for example, just discovered 41 new alien planets in one fell swoop, raising its total to more than 2,300 suspected planets outside our solar system.
To put that number in perspective, planetary scientist Alex Parker made the following animation of Kepler's top 2,299 planet candidates, all shown together as if they orbited a single star. Each one is drawn to scale, Parker notes on Vimeo, with an accurate radius, orbital period and orbital distance–see above.
Parker, who works at the Harvard-Smithsonian Center for Astrophysics, says he made the video to help people grasp the enormity of Kepler's discoveries. "I wanted to convey the astounding number of planet candidates Kepler has found in a way that would really impact the person watching this video," he says in a statement. . . .