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Lava World Baffles Astronomers: Planet Kepler-78b ‘Shouldn’t Exist’

October 31, 2013 Leave a comment

Kepler-78b is a planet that shouldn’t exist. This scorching lava world circles its star every eight and a half hours at a distance of less than one million miles — one of the tightest known orbits. According to current theories of planet formation, it couldn’t have formed so close to its star, nor could it have moved there.

Kepler-78b is a planet that shouldn’t exist. This scorching lava world, shown here in an artist’s conception, circles its star every eight and a half hours at a distance of less than one million miles. According to current theories of planet formation, it couldn’t have formed so close to its star, nor could it have moved there. (Credit: David A. Aguilar (CfA))

“This planet is a complete mystery,” says astronomer David Latham of the Harvard-Smithsonian Center for Astrophysics (CfA). “We don’t know how it formed or how it got to where it is today. What we do know is that it’s not going to last forever.”

“Kepler-78b is going to end up in the star very soon, astronomically speaking,” agrees CfA astronomer Dimitar Sasselov.

Not only is Kepler-78b a mystery world, it is the first known Earth-sized planet with an Earth-like density. Kepler-78b is about 20 percent larger than Earth, with a diameter of 9,200 miles, and weighs almost twice as much. As a result it has a density similar to Earth’s, which suggests an Earth-like composition of iron and rock.

Read more: http://www.sciencedaily.com/releases/2013/10/131030142915.htm

 

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NASA’s Black-Hole-Hunter Catches Its First 10 Supermassive Black Holes

September 10, 2013 Leave a comment

Sep. 9, 2013 — NASA’s black-hole-hunter spacecraft, the Nuclear Spectroscopic Telescope Array, or NuSTAR, has “bagged” its first 10 supermassive black holes. The mission, which has a mast the length of a school bus, is the first telescope capable of focusing the highest-energy X-ray light into detailed pictures.

 

An optical color image of galaxies is seen here overlaid with X-ray data (magenta) from NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR). (Credit: NASA/JPL-Caltech)
 

The new black-hole finds are the first of hundreds expected from the mission over the next two years. These gargantuan structures — black holes surrounded by thick disks of gas — lie at the hearts of distant galaxies between 0.3 and 11.4 billion light-years from Earth.

“We found the black holes serendipitously,” explained David Alexander, a NuSTAR team member based in the Department of Physics at Durham University in England and lead author of a new study appearing Aug. 20 in The Astrophysical Journal. “We were looking at known targets and spotted the black holes in the background of the images.”

Additional serendipitous finds such as these are expected for the mission. Along with the mission’s more targeted surveys of selected patches of sky, the NuSTAR team plans to comb through hundreds of images taken by the telescope with the goal of finding black holes caught in the background.

 

Read more: http://www.sciencedaily.com/releases/2013/09/130909154918.htm

NASA’s Chandra Observatory Catches Giant Black Hole Rejecting Material

September 2, 2013 Leave a comment

Aug. 29, 2013 — Astronomers using NASA’s Chandra X-ray Observatory have taken a major step in explaining why material around the giant black hole at the center of the Milky Way Galaxy is extraordinarily faint in X-rays. This discovery holds important implications for understanding black holes.

Supermassive black hole Sagittarius A* at the heart of the Milky Way galaxy. (Credit: X-ray: NASA/UMass/D.Wang et al., IR: NASA/STScI)

New Chandra images of Sagittarius A* (Sgr A*), which is located about 26,000 light-years from Earth, indicate that less than 1 percent of the gas initially within Sgr A*’s gravitational grasp ever reaches the point of no return, also called the event horizon. Instead, much of the gas is ejected before it gets near the event horizon and has a chance to brighten, leading to feeble X-ray emissions.

These new findings are the result of one of the longest observation campaigns ever performed with Chandra. The spacecraft collected five weeks’ worth of data on Sgr A* in 2012. The researchers used this observation period to capture unusually detailed and sensitive X-ray images and energy signatures of super-heated gas swirling around Sgr A*, whose mass is about 4 million times that of the sun.

Read more: http://www.sciencedaily.com/releases/2013/08/130829142311.htm

Giant storms on Saturn: Nasa captures incredible view of ‘rose’ hurricane 20 times bigger than any on Earth


  • Hurricane’s eye is about 1,250 miles (2,000 kilometers) wide, 20 times larger than the average hurricane eye on Earth
  • Hurricane swirls inside a large, mysterious, six-sided weather pattern known as the hexagon

By MARK PRIGG

PUBLISHED: 17:40 GMT, 29 April 2013 | UPDATED: 18:49 GMT, 29 April 2013

At first glance, it resembles a giant rose, surrounded by green foliage.

However, in fact this is a huge, violent storm of the surface of Saturn – and one that has been brewing for years

In high-resolution pictures and video, scientists say the hurricane’s eye is about 1,250 miles (2,000 kilometers) wide, 20 times larger than the average hurricane eye on Earth.

The spinning vortex of Saturn's north polar storm The spinning vortex of Saturn’s north polar storm resembles a deep red rose of giant proportions surrounded by green foliage in this false-color image from NASA’s Cassini spacecraft. Measurements have sized the eye at a staggering 1,250 miles (2,000 kilometers) across with cloud speeds as fast as 330 miles per hour (150 meters per second).
Nasa’s Cassini spacecraft has provided scientists the first close-up, visible-light views of a behemoth hurricane swirling around Saturn’s north pole.

Thin, bright clouds at the outer edge of the hurricane are traveling 330 mph(150 meters per second). The hurricane swirls inside a large, mysterious, six-sided weather pattern known as the hexagon.

‘We did a double take when we saw this vortex because it looks so much like a hurricane on Earth,’ said Andrew Ingersoll, a Cassini imaging team member at the California Institute of Technology in Pasadena.

‘But there it is at Saturn, on a much larger scale, and it is somehow getting by on the small amounts of water vapor in Saturn’s hydrogen atmosphere.’

Scientists will be studying the hurricane to gain insight into hurricanes on Earth, which feed off warm ocean water.

Read more: http://www.dailymail.co.uk/sciencetech/article-2316699/The-breathtaking-rose-storms-Saturn-captured-Cassini.html#ixzz2S7oHC54E

Scientists Detect ‘Dark Lightning’ Energy Burst Linked to Visible Lightning

April 25, 2013 1 comment

Apr. 24, 2013 — Researchers have identified a burst of high-energy radiation known as ‘dark lightning” immediately preceding a flash of ordinary lightning. The new finding provides observational evidence that the two phenomena are connected, although the exact nature of the relationship between ordinary bright lightning and the dark variety is still unclear, the scientists said.

Three images, left to right, of the same thundercloud depict a less-than-10-milliseconds-long sequence of events: (left) formation within the cloud of a small channel, or ‘leader,’ of electrical conductivity (yellow line) with weak emission of radio signals (ripples), to (middle) a burst of both dark lightning (pink) and radio waves (larger ripples), to (right) a discharge of bright lightning and more radio waves. (Credit: Studio Gohde)

“Our results indicate that both these phenomena, dark and bright lightning, are intrinsic processes in the discharge of lightning,” said Nikolai Østgaard, who is a space scientist at the University of Bergen in Norway and led the research team.

He and his collaborators describe their findings in an article recently accepted in Geophysical Research Letters — a journal of the American Geophysical Union.

Dark lightning is a burst of gamma rays produced during thunderstorms by extremely fast moving electrons colliding with air molecules. Researchers refer to such a burst as a terrestrial gamma ray flash.

Read more:http://www.sciencedaily.com/releases/2013/04/130424210319.htm

Curiosity Chills Out In Safe Mode While NASA Analyzes Computer Glitch


Corrupted files may be the fault of cosmic radiation.
By Rebecca Boyle Posted 03.04.2013
 
A Rover In Full

A Rover In Full NASA/JPL-Caltech

NASA’s Mars rover Curiosity paused its work over the weekend and is chilling in safe mode on Mars, while engineers on Earth try to resolve a computer glitch. The rover switched to a backup computer, but operations are on hiatus while NASA engineers work on the problem.

Last week, engineers noticed a glitch in the flash memory on one of the rover’s two computers. Curiosity had normal communications with Earth on Wednesday, Feb. 27, but like an annoying Facebook friend, it updated its status yet included no actual information. In the status update, engineers learned the rover did not go to sleep when planned, and when they started diagnosing the problem, they realized the main A-side computer had some corrupted files.

Read more: http://www.popsci.com/technology/article/2013-03/today-mars-curiosity-chills-safe-mode-while-nasa-analyzes-computer-glitch

NASA’s Van Allen Probes Reveal a New Radiation Belt Around Earth


Feb. 28, 2013 — NASA’s Van Allen Probes mission has discovered a previously unknown third radiation belt around Earth, revealing the existence of unexpected structures and processes within these hazardous regions of space.

Two giant swaths of radiation, known as the Van Allen Belts, surrounding Earth were discovered in 1958. In 2012, observations from the Van Allen Probes showed that a third belt can sometimes appear. The radiation is shown here in yellow, with green representing the spaces between the belts. (Credit: NASA/Van Allen Probes/Goddard Space Flight Center)

Previous observations of Earth’s Van Allen belts have long documented two distinct regions of trapped radiation surrounding our planet. Particle detection instruments aboard the twin Van Allen Probes, launched Aug. 30, quickly revealed to scientists the existence of this new, transient, third radiation belt.

The belts, named for their discoverer, James Van Allen, are critical regions for modern society, which is dependent on many space-based technologies. The Van Allen belts are affected by solar storms and space weather and can swell dramatically. When this occurs, they can pose dangers to communications and GPS satellites, as well as humans in space.

Read more: http://www.sciencedaily.com/releases/2013/02/130228155430.htm