New York Times, By Dennis Overbye, February 11
A team of physicists who can now count themselves as astronomers announced on Thursday that they had heard and recorded the sound of two black holes colliding a billion light-years away, a fleeting chirp that fulfilled the last prophecy of Einstein’s general theory of relativity.
That faint rising tone, physicists say, is the first direct evidence of gravitational waves, the ripples in the fabric of space-time that Einstein predicted a century ago. And it is a ringing (pun intended) confirmation of the nature of black holes, the bottomless gravitational pits from which not even light can escape, which were the most foreboding (and unwelcome) part of his theory.
Astronomy Now, January 14
Records are made to be broken, as the expression goes, but rarely are records left so thoroughly in the dust. Stunned astronomers have witnessed a cosmic explosion about 200 times more powerful than a typical supernova — events which already rank amongst the mightiest outbursts in the universe — and more than twice as luminous as the previous record-holding supernova.
At its peak intensity, the explosion — called ASASSN-15lh — shone with 570 billion times the brightness of the Sun. If that statistic does not impress, consider that this luminosity level is approximately 20 times the entire output of the 100 billion stars comprising our Milky Way galaxy.
The record-breaking blast is thought to be an outstanding example of a “superluminous supernova,” a recently discovered, supremely rare variety of explosion unleashed by certain stars when they die. Scientists are frankly at a loss, though, regarding what sorts of stars and stellar scenarios might be responsible for these extreme supernovae.
Washington Post, By Rachel Feltman, October 28
For the first time ever, molecular oxygen has been found on a comet. Comet 67P/Churyumov–Gerasimenko, currently being orbited by the European Space Agency’s Rosetta spacecraft, is the subject of a study published Wednesday in Nature. According to ESA researchers, the oxygen present in the comet’s surrounding gasses has likely been there since the formation of the comet.
“It is the most surprising discovery we have made so far, because oxygen was not among the molecules expected in a cometary coma,” the University of Bern’s Kathrin Altwegg said at a news conference Tuesday held by Nature. Altwegg, one of the new study’s authors, is in charge of Rosetta’s ROSINA (Rosetta Orbiter Spectrometer for Ion and Neutral Analysis). This instrument is used to “sniff” out the atmospheric composition of the comet.
“We all went a little bit into denial,” she said. The result was so unexpected that the team wanted to be absolutely certain that the oxygen wasn’t the result of some kind of instrumentation failure or contamination. But the oxygen, Altwegg explained, “follows the comet very well.” The team has observed that oxygen levels are higher close to the comet, and disappear as the instrument pulls away.
But no current models of the solar system’s formation would allow for molecular oxygen to get locked away inside a comet. Oxygen is highly reactive, so it’s always been assumed that any molecular oxygen present would bond with the abundantly available hydrogen. The researchers were shocked to see that oxygen could “survive” in its molecular form for billions of years.
The Guardian, By Alan Yuhas, January 12
New York – Senator Ted Cruz will chair the committee that oversees science and Nasa in the new Republican-controlled Congress, raising fears that the conservative Texan will cut funding to the space agency and science programs.
Cruz’s appointment to the space, science and competitiveness subcommittee comes amid a broad shift of power in the Senate, where the GOP won a majority in the 2014 midterm elections. Cruz was the top Republican on the subcommittee before the elections.
He has publicly stated support for Nasa but has also attempted at least once to cut the agency’s funding, arguing that larger government cuts necessitated changes to the space program’s budget. In 2013, Cruz both tried to reduce Nasa’s budget and said: “It’s critical that the United States ensure its continued leadership in space.”
Cruz has constituents invested in the space agency’s future – for instance, Nasa employees and contractors at the Johnson Space Center in Houston.
Cruz has also spoken out against decades of science that indicate climate change, telling CNN last year that in “the last 15 years, there has been no recorded warming” to support “a so-called scientific theory”. His vociferous opposition to the Environmental Protection Agency (EPA) and his support of extreme budget cuts could spell trouble for Nasa’s less prominent programs, such as its own climate research and sophisticated supercomputers.
The Wall Street Journal, December 18
It’s been a pretty amazing year for India’s space agency: reaching Mars orbit at first attempt and on a tight budget then clubbing together with the United States for future explorations of the Red planet. On Thursday morning the Indian Space Research Organization wrapped up 2014 with the successful launch of a rocket that will help it discover if it has the capacity to put an Indian astronaut into space, and bring them home again.
The rocket that lifted off from southern India at 09:32 Indian Standard Time carried an un-manned crew capsule that scientists wanted to ensure could re-enter the Earth’s atmosphere without burning up.
The so-called crew-module atmospheric re-entry experiment is part of India’s plan to send a person into space within the next eight years. The capsule separated from the rocket successfully at 126 kilometers above the Earth’s surface and re-entered the Earth’s atmosphere as hoped and deploying parachutes. It was expected to land in the Bay of Bengal and be recovered by the Indian Coast Guard.
BBC, By Rebecca Morelle, December 10
Scientists have dealt a blow to the theory that most water on Earth came from comets.
Results from Europe’s Rosetta mission, which made history by landing on Comet 67P in November, shows the water on the icy mass is unlike that on our planet. The results are published in the journal Science.
The authors conclude it is more likely that the water came from asteroids, but other scientists say more data is needed before comets can be ruled out.
The team found that there was far more heavy water on Comet 67P than on Earth.
Prof Altwegg told BBC Radio 4’s Inside Science programme: “It is the highest-ever measured ratio of heavy water relative to light water in the Solar System. “It is more than three times higher than on the Earth, which means that this kind of comet could not have brought water to the Earth.”
The Orion spacecraft could eventually take astronauts to an asteroid or Mars.
Scientific American, By Clara Moskowitz, December 3
Cape Canaveral, FL – NASA’s Kennedy Space Center here has been relatively quiet since the space shuttles retired three years ago. But now the site is bustling with media, top NASA officials are traveling to Florida, and engineers are busy readying the launch pad to blast off a brand new spaceship. The cone-shaped Orion capsule is NASA’s next venture in human spaceflight, and it will eventually carry people to an asteroid or maybe Mars—if the U.S. can find the funding and political will.
No one will be riding Orion on Thursday, when it makes its maiden launch in a test flight from Cape Canaveral Air Force Station at 7:05 a.m. EST. This trial run will check out Orion’s basic design by launching it to an altitude of 5,800 kilometers (15 times farther from the Earth’s surface than the International Space Station) before it splashes down four hours later in the Pacific Ocean. “This is the first human-rated spacecraft that’s gone beyond low-Earth orbit in 42 years,” Mike Hawes, Orion program manager at Lockheed Martin, the spacecraft’s prime contractor, said Tuesday in a preflight NASA news conference. “It is a big deal.”
NPR: NASA Prepares To Test New Spacecraft (That You’ve Likely Never Heard Of)
(Yoshikazu Tsuno/AFP/Getty Images)
more at : Vox
Business Insider, By Leslie Baehr
Human-induced warming is sending Earth into frightening and uncharted climate territory — but humans are not the first force to cause colossal changes to our climate.
Other celestial bodies, including planets, tug at Earth causing it to move in ways that affect our ice caps in history-shaping ways, as discussed by narrator and astrophysicist Neil deGrasse Tyson on Sunday’s Cosmos: A Spacetime Odyssey.
For example, the pull of the planets influences Earth’s tilt. They cause Earth’s axis to wobble in a circular motion similar to the spin of a top. You can can see these movements in the Cosmos GIF to the left.
If you could stick a pen out of Earth’s north pole, it would draw a circle about every 26,000 years. In 14,000 AD for example, our north star was not Polaris, as it is now, but Vega. In 12,000 years , Vega will be our north star again.
The pull of the planets also cause the Earth’s tilt to change between 22.1 and 24.5 degrees over 41,000 years. When our tilt is more extreme, seasons can be more severe, with warmer summers and cooler winters. When the tilt is less, we get cooler summers and milder winters. Currently our tilt is about 23.4 degrees — near the middle.
More at the link
Discovery of gravitational waves by Bicep telescope at south pole could give scientists insights into how universe was born
The Guardian, By Stuart Clark, March 14
There is intense speculation among cosmologists that a US team is on the verge of confirming they have detected “primordial gravitational waves” – an echo of the big bang in which the universe came into existence 14bn years ago.
Rumours have been rife in the physics community about an announcement due on Monday from the Harvard-Smithsonian Center for Astrophysics. If there is evidence for gravitational waves, it would be a landmark discovery that would change the face of cosmology and particle physics.
Gravitational waves are the last untested prediction of Albert Einstein’s General Theory of Relativity. They are minuscule ripples in the fabric of the universe that carry energy across space, somewhat similar to waves crossing an ocean. Convincing evidence of their discovery would almost certainly lead to a Nobel prize.
“If they do announce primordial gravitational waves on Monday, I will take a huge amount of convincing,” said Hiranya Peiris, a cosmologist from University College London. “But if they do have a robust detection … Jesus, wow! I’ll be taking next week off.”
For decades, cosmologists have thought that the signature of primordial gravitational waves could be imprinted on this radiation. “It’s been called the Holy Grail of cosmology,” says Peiris, “It would be a real major, major, major discovery.”