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Kepler space telescope discovers ‘strange’ planets
THIS UNIVERSE Trends
Universe is older than previously thought Meteor lights up night sky over eastern North America
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Kepler
space telescope discovers ‘strange’ planets The truth is
out there, but when it comes to the search for other planets beyond
our Solar System the truth has turned out to be far stranger than
science fiction. Scientists looking for habitable “exoplanets”
similar to Earth are astounded by the shear range and diversity of the
weird worlds orbiting distant stars — some shining like diamonds,
others as black as coal.
“We are finding an absolutely enormous range of planet types. It has come as quite a surprise,” said William Borucki of NASA’s Ames Research Centre in Moffat Field, California, the principal investigator on the Kepler Mission to find habitable planets beyond our Solar System. Among them is one that resembles Tatooine, the home of Star Wars hero Luke Skywalker. Kepler-16b has two suns setting over the horizon instead of just one, but in this case it has not thought to be habitable. The Kepler space telescope, launched four years ago, has scoured the sky for the faint twinkles of starlight caused as a distant planet passes across the face of its star. Kepler has so far identified 2,740 possible exoplanets, with confirmed planet discoveries numbering 114 to date. Up to 90 per cent of the possible candidate planets are likely to be confirmed eventually, Dr Borucki said. Although there are about 350 exoplanets about the size of the Earth, none so far has been found in the “habitable zone”, otherwise known as the Goldilocks distance from a star, where it is not too hot, nor too cold for liquid water, and hence life, to exist. “We are beginning to find planetary systems with more than one planet orbiting a star, and so far they are all rather different to our own Solar System,” Dr Borucki said. “There are about 40 to 50 planetary candidates in the habitable zone but there are no Earth-sized planets there. We have not yet found Earth-sized planets in the habitable zone,” he said. Analysis of the planetary orbits, motions and spectra of light absorbed by a planet’s atmosphere have revealed a remarkably range of planets — far more than theoreticians had predicted at the start of the mission, Dr Borucki said. While some planets are as dense as iron, with oceans of molten metal, others appear to be feather-light heavenly bodies composed of gaseous or rarefied material, he said. “We have found a planet with the density of Styrofoam. It would float in the ocean, in fact, with most of it sticking out of the water. Since then we have found a planet with half that density, so the range of densities is just beyond belief,” Dr Borucki said. “We are finding planets that are just a little bigger than the Earth but with the density of iron. It is orbiting very close to its star, with an orbiting time of less than one day. It is so hot it must be molten, so it must have oceans of lava or possibly molten iron,” he said. Some planets have turned out to be nearly as small as the Moon, while others are several times the size of Jupiter — the biggest planet in the Solar System — which has defied conventional logic of how planet’s form, Dr Borucki said. “We are finding planets bigger than Jupiter, which is a surprise in that it was believed that planets could not be larger than Jupiter because if you add mass to a planet we thought it would just get denser, not bigger,” Dr Borucki said at the Royal Society in London. “We are finding planets that are two or three times the size of Jupiter, and Jupiter is the size of a small star so we are finding planets as big as stars….We have found that planets can get bigger by some process and we don’t understand that process,” he said. Some planets are orbiting their stars together, which theory suggests would demand that they have similar densities. But scientists have found two closely-orbiting planets with very different densities — one is made of rock while the other is composed of gas. “What that tells you is that our concept of how planetary systems, based on how our own Solar System is put together, is probably not applicable for many of these other solar systems,” Dr Borucki said. Even the orbits of the exoplanets have proven to be unconventional. Before Kepler, most planetary scientists thought that rocky planets like Earth would orbit close to their star, while gaseous planets such as Jupiter would orbit further out – but large gas planets have been found in very close orbits to their stars. “We have found everything different from what people had predicted, other than one of the predictions which was that during the formation of a star a planet could form,” Dr Borucki said. “That was quite right. There are lots and lots of planets but the orbits are not where we expected them to be,” he said. “We are seeing or will see thousands of planets, so our expectations are reasonably consistent at this stage of the game. “But does this huge number of planets imply life? We can’t tell that. We haven’t found an Earth in the habitable zone. So we don’t know whether there are other Earths out there at this point,” he said. — The Independent |
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THIS UNIVERSE Q. Can an airplane fly smoothly if any of its window glass is broken or open?" A. If the airplane is small and flies at low speed and at low altitude without pressurisation of the cabin, then it might be able to balance even after losing a window glass. Otherwise the loss of a window will lead to depressurisation making the airplane rather unstable and it should land as soon as possible to avert a disaster. Q. I am a HSLC candidate from a vernacular-medium school of Assam. I am very much interested in studies related to extraterrestrial influence on Earth. I have studied the researches of Daniken, Josef Blumrikh etc and am now studying about Carl Sagan as well as SETI. But some experts of our state told me that all these things are just fiction. What is your opinion? How can I study further to do some research-oriented tasks in this field? A. There is no alternative to study and independent thinking. Your main interestseems to be in the possible existence of life elsewhere in the universe. This will always remain an open question because it seems rather unreasonable that our small solar system is the only location in the mammoth universe that allowed the growth of life. Simultaneously, we might have to allow that life might manifest itself in such diverse forms that we might find it difficult to recognise it. This is a serious and valid field of exploration involving a large number of disciplines in physical and biological sciences, and philosophy. You will go on finding rich material to read and interpret. Q. Can our earth exist without the other planets of the universe? Please explain. A. Your query could be re-phrased as “could our earth have formed as the only planet in the solar system?” Thinking about the likely origin of our solar system I would say that it would be highly unlikely. I think solar systems do not enjoy having very small families. I can’t find strong physical arguments for such a statement, but probability wise this seems to be very likely. Of course, if I don’t have to think about their origins and was told that the Creator had decided to place a star and an earth-like planet, borrowed from a friend of His, to start living as a unique family, will I have any strong scientific arguments against, I would be hard put to object.
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Universe is older than previously thought CAPE CANAVERAL, Florida: Closer scrutiny of radiation left over from the creation of the universe shows the Big Bang took place about 13.8 billion years ago, 100 million years earlier than previous estimates, scientists said. The findings are among the first results from analysis of data collected by the European Space Agency’s Planck spacecraft, which is providing the most detailed look to date at the remnant microwave radiation that permeates the universe. Meteor lights up night sky over eastern North America NEW YORK:
A meteor bright enough to be classified as a fireball lit up the night sky over eastern North America, providing a spectacle witnessed in at least 13 states, Washington, D.C. and two Canadian provinces, the American Meteor Society said. The society verified more than 300 witness sightings from Ontario and Quebec down to the southern US state of North Carolina with more than 100 reports yet to be reviewed, said Mike Hankey, an observer for the American Meteor Society. NASA steps up security after the arrest of former contractor CAPE CANAVERAL, Florida: NASA has shut down access to an online database and banned new requests from Chinese and some other foreign nationals seeking access to its facilities amid mounting concerns about espionage and export control violations, the US space agency’s administrator said. The security measures include a complete ban on remote computer access by Chinese and some other non-US contractors already working at NASA centers, agency chief Charles Bolden said at a congressional oversight hearing in Washington. — Reuters
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