Tag Archives: planets

What Do Sunsets Look Like From Other Planets?

A University of Exeter astrophysicist has shown what sunsets look like on planets outside our solar system.

He has worked out the colour of sunsets on two planets: HD 209458 b and HD 189733 b, known as ‘extrasolar planets’ because they are outside our solar system.

Extrasolar planets orbit stars, in a similar way to the Earth orbiting the Sun. Professor Frédéric Pont of the University of Exeter has used the extrasolar planets’ ‘transmission spectrum’, taken by the Hubble Space Telescope, to work out the colour of the ‘sunsets’ created by these stars.

Writing on the website ExoClimes.com, where he has posted the two sunset images he has produced, Professor Pont said: “Unlike its sister planet HD ’189, the planet HD ’209 (‘Osiris’) has a sunset that looks truly alien. The star is white outside the atmosphere, since its temperature is close to that of the Sun. It then acquires a bluish tinge as it sinks deeper, because the absorption by the broad wings of the neutral sodium lines (the spectral lines responsible for the gloomy orange of sodium street lighting) remove the red and orange from the star light. (more…)

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Physicists Set Strongest Limit on Mass of Dark Matter

*Brown University physicists have set the strongest limit for the mass of dark matter, the mysterious particles believed to make up nearly a quarter of the universe. The researchers report in Physical Review Letters that dark matter must have a mass greater than 40 giga-electron volts. The distinction is important because it casts doubt on recent results from underground experiments that have reported detecting dark matter.*

PROVIDENCE, R.I. [Brown University] — If dark matter exists in the universe, scientists now have set the strongest limit to date on its mass.

In a paper to be published on Dec. 1 in Physical Review Letters (available in pdf), Brown University assistant professor Savvas Koushiappas and graduate student Alex Geringer-Sameth report that dark matter must have a mass greater than 40 giga-electron volts in dark-matter collisions involving heavy quarks. (The masses of elementary particles are regularly expressed in term of electron volts.) Using publicly available data collected from an instrument on NASA’s Fermi Gamma-ray Space Telescope and a novel statistical approach, the Brown pair constrained the mass of dark matter particles by calculating the rate at which the particles are thought to cancel each other out in galaxies that orbit the Milky Way galaxy. (more…)

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NASA Develops New Game-Changing Technology

Two NASA California centers have been selected to develop new space-aged technologies that could be game-changers in the way we look at planets from above and how we safely transport robots or humans through space and bring them safely back to Earth.

NASA’s Jet Propulsion Laboratory in Pasadena, Calif., will use advanced compound semiconductor materials to develop new technologies for the High Operating Temperature Infrared Sensor Demonstration. The higher the temperature at which an infrared detector can operate, the less power is required to cool it. Reduced power needs can translate into operational cost and system weight savings. If successful, this sensor technology could be used in many future NASA Earth and planetary science instruments, as well as for U.S. commercial and defense applications. (more…)

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Astronomers Find Bounty of Failed Stars

*One youngster only six times heftier than Jupiter*

TORONTO, ON – A University of Toronto-led team of astronomers has discovered over two dozen new free-floating brown dwarfs, including a lightweight youngster only about six times heftier than Jupiter, that reside in two young star clusters. What’s more, one cluster contains a surprising surplus of them, harbouring half as many of these astronomical oddballs as normal stars.

“Our findings suggest once again that objects not much bigger than Jupiter could form the same way as stars do. In other words, nature appears to have more than one trick up its sleeve for producing planetary mass objects,” says Professor Ray Jayawardhana, Canada Research Chair in Observational Astrophysics at the University of Toronto and leader of the international team that made the discovery. (more…)

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Sun and Planets Constructed Differently, Analysis from Nasa Mission Suggests

The sun and the solar system’s rocky inner planets, including the Earth, may have formed differently than previously thought, according to UCLA scientists and colleagues analyzing samples returned by NASA’s Genesis mission.

The data from Genesis, which collected material from the solar wind blowing from the sun, reveal differences between the sun and planets with regard to oxygen and nitrogen, two of the most abundant elements in our solar system, the researchers report in two studies in the June 24 issue of the journal Science. And although the differences are slight, the research could help determine how our solar system evolved. (more…)

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Why Some Planets Orbit the Wrong Way; Extrasolar Insights into Our Solar System

More than 500 extrasolar planets–planets that orbit stars other than the sun–have been discovered since 1995. But only in the last few years have astronomers observed that in some of these systems, the star is spinning one way and the planet is orbiting that star in the opposite direction.

“That’s really weird, and it’s even weirder because the planet is so close to the star,” said Frederic A. Rasio, a theoretical astrophysicist at Northwestern University. “How can one be spinning one way and the other orbiting exactly the other way? It’s crazy. It so obviously violates our most basic picture of planet and star formation.” (more…)

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Four Planets Huddle Up Before Dawn Next Week

AUSTIN, Texas — Four of the five planets visible to the unaided eye huddle quite close together in the pre-dawn sky next week, according to the editors of StarDate magazine.

On the morning of May 10, Venus and Jupiter will stand side by side, quite low in the east, as dawn brightens. If you have a horizon clear of buildings and trees, they will be easy to spot. They are the brightest objects in the night sky after the moon. Venus is the brighter of the two. Jupiter is to its left. (more…)

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Go Ask ALICE: Learning About the Big Bang

Nearly 14 billion years ago, the universe began with a bang — a big one.

Scientists believe that the universe and everything within it began as an extremely hot, dense “soup” that eventually gave rise to galaxies, stars, planets and life and that continues to expand to this day.

Now scientists around the world are pushing back the frontiers of our understanding about the moment the universe was born using the Large Hadron Collider (LHC), a giant particle accelerator at CERN (the European Organization for Nuclear Research) near Geneva, Switzerland. (more…)

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