- Identical Twins Diet Challenge. One Gives Up Fat, The Other Sugar. Who Wins?
- Where Does All Our Oil Come From?
- Out of Fuel, Messenger Spacecraft Will Slam Into Mercury
- Repeating Light Signal May Be Two Supermassive Black Holes Set To Collide as Galaxies Merge
- Evidence the Pharaohs Did Not Build the Sphinx
- Unconventional Science on Coast To Coast Radio
- You Are Who Your Pet Thinks You Are ~ Video
- Mysterious 'Cold Spot' In The Universe ~ What's Not There Puzzles Scientists
- The 'Why the F*** Are We So Fat?!' 30 Day Experiment ~ Day 3 ~ Fables
- Why Do We Have Different Blood Types?
- Is There a Mirror Universe?
- Is the Flow of Time Merely an Illusion? The B-Theory of Time ~ With Brian Greene
- Hidden Dimensions: Exploring Hyperspace ~ World Science Festival
Posted: 20 Apr 2015 09:44 PM PDT
Click to zoom
Posted: 20 Apr 2015 09:31 PM PDT
Posted: 20 Apr 2015 09:28 PM PDT
Excerpt from usatoday.com
Gravity soon will kill the Messenger.
The NASA spacecraft that launched in 2004 from Cape Canaveral, Fla., and became the first to orbit Mercury in 2011 is on course to crash into the planet's surface April 30 at more than 8,700 mph.
"Messenger is going to create a new crater on Mercury at some point in the very near future," said John Grunsfeld, head of NASA's Science Mission Directorate. "Rather than be sad about that, we really are celebrating just a fantastic mission."
Messenger is short for MErcury Surface, Space ENvironment, GEochemistry, and Ranging.
Mission scientists today said the spacecraft's mapping of the planet and discoveries about its makeup have reshaped understanding of Mercury and ideas about how early planets formed.
For example, Messenger confirmed the existence of ice deposits made of water at the poles of the planet closest to the sun.
Those deposits are covered by a mysterious dark layer of what could be organic material delivered by the same objects that brought the water ice.
“Messenger is going to create a new crater on Mercury at some point in the very near future. ”
John Grunsfeld, NASA
The material offers "a record in these poles of the delivery, probably from the outer solar system, not only of water ice but of what on our planet were once some of the building blocks of organic chemistry and life, here on the planet closest to the sun," said Sean Solomon, the mission's principal investigator from Columbia University. "So Mercury therefore preserves a record of some very interesting processes in solar system history."
Solomon said findings about Mercury's surface composition would make scientists "reject most of the ideas for how Mercury was assembled as a planet at the beginning of the history of the solar system" and come up with new ideas to explain the chemistry.
Messenger already has run out of fuel, but engineers have come up with clever ways to extend its life, including using helium intended to pressurize propellant tanks to provide an extra boost.
One more orbital maneuver is planned April 24. Data collection will continue until 10 or 15 minutes before impact and will continue to be analyzed for years.
"We should be studying Mercury science long past when our crater is created," said Helene Winters, project manager from Johns Hopkins University's Applied Physics Laboratory.
NASA concluded a "celebration" of the mission with a Twitter message attributed to the spacecraft.
"Please give my thanks to the team," it said. "It's been a wonderful and exciting trip."
NASA has had only two missions to Mercury, Messenger and a flyby of Mariner 10 in 1974 and '75. Still those who watched the sky have known of the planet since ancient times.
• Closest. It orbits about 36 million miles from the sun, the closest of the planets.
• Smallest. It is the smallest planet in our solar system, slightly larger than Earth's moon.
• Long. One of its days is the equivalent of 59 Earth days.
• Short. One of its years is the equivalent of 88 Earth days.
• Extreme. Daytime temperatures can reach 800 degrees Fahrenheit; night can be minus-290 degrees.
• Scarred. Mercury's atmosphere isn't thick enough to burn off meteors before they hit the planet's rocky surface, so it has many craters like our moon.
• Alone. It has no moon, and if it were in a direct line with Venus, it still would be more than 31 million miles away.
Posted: 20 Apr 2015 09:16 PM PDT
Excerpt from iflscience.com
An unusual, repeating light signal in the distance may be coming from the final stages of a merger between two supermassive black holes. At just a few hundredths of a light-year apart, they could be merging in a mere one million years. An event like this has been predicted based on theory, but has never been observed before, according to a new study published in Nature this week.
The supermassive black holes at the center of most large galaxies (including ours) appear to co-evolve with their host galaxies: As galaxies merge, their black holes grow more massive too. Since we can’t actually see black holes, researchers look for their surrounding bands of material called accretion disks, which are produced by the intense pull of the black hole’s gravity. The disks of supermassive black holes can release vast amounts of heat, X-rays, and gamma rays that result in a quasar—one of the most luminous objects in the universe.
Caltech’s Matthew Graham and colleagues noticed the light signal coming from quasar PG 1302-102 while studying variability in quasar brightness using data from the Catalina Real-Time Transient Survey, which continuously monitored 500 million celestial light sources across 80 percent of the sky with three ground telescopes.
The team noticed 20 quasars emitting periodic optical signals, which was unexpected since the light curves of quasars are usually chaotic. (That’s because material from the accretion disk spiral randomly into the black hole.) And of these, PG 1302-102’s clean, strong signal, which repeated every five years or so, stood out. "It has a really nice smooth up-and-down signal, similar to a sine wave, and that just hasn't been seen before in a quasar," Graham explains in a news release. (See illustration above.)
Quasars typically have one emission line that’s viewed as a symmetric curve. "But with this quasar, it was necessary to add a second emission line with a slightly different speed than the first one in order to fit the data," says study co-author Eilat Glikman of Middlebury College. "That suggests something else, such as a second black hole, is perturbing this system." A supermassive black hole binary was the most likely explanation: Any object that’s less dense than a secondary black hole would be disrupted by the gravity of the primary black hole.
"The end stages of the merger of these supermassive black hole systems are very poorly understood," Graham says. "The discovery of a system that seems to be at this late stage of its evolution means we now have an observational handle on what is going on."
Study co-author Daniel Stern of JPL adds: "The black holes in PG 1302-102 are, at most, a few hundredths of a light-year apart and could merge in about a million years or less.” And when that happens, The New York Times reports, it’ll release as much energy as 100 million supernova explosions.
Posted: 20 Apr 2015 09:11 PM PDT
Click to zoom
Posted: 20 Apr 2015 09:00 PM PDT
Posted: 20 Apr 2015 08:55 PM PDT
Excerpt from huffingtonpost.com
Your pet loves you unconditionally -- but do you offer yourself the same courtesy?
Our furry friends bring us a lot of joy (and even some health benefits) but perhaps one of their quietest, yet best qualities is what they can teach us about loving ourselves. The short of it: Look at yourself the way your dog or cat looks at you.
Self-acceptance is key to a happier life (science says so!) but often our minds berate our abilities and focus on our flaws. Our pets don't see us that way.
As the video above shows, Fluffy is happy with us no matter what -- even if we made a mistake at work or skipped the gym. If you're feeling down, give it a watch. You may just gain a little perspective by looking through an animal's eyes.
Posted: 20 Apr 2015 08:41 PM PDT
Excerpt from techtimes.com
Astronomers studying the largest detected structure in the universe, 1.8 billion light years wide, say they've figured out what it is — or actually isn't, in a sense, because it's a giant and unusually empty hole. It was discovered in an astronomical survey trying to discover why around 10,000 expected galaxies were missing from the portion of the sky being observed, they say. Dubbed a "supervoid" and distinctive for its unexpected emptiness, it is "the largest individual structure ever identified by humanity," says study leader István Szapudi of the University of Hawaii at Manoa. His research team was looking at the region that was previously found to be an area where the cosmic microwave background radiation is much cooler that the average surrounding background temperatures, which astronomers quickly named the Cold Spot. The existence of such a large, cold area was out of step with most models of the evolution of the universe after the Big Bang, which allowed for some warmer and cooler regions to emerge in the early days of the universe, but nothing on the scale of the Cold Spot.
The giant region of emptiness detected may at least partly explain the very existence of the Cold Spot, the researchers suggest, with the supervoid sucking energy out of the cosmic background radiation that travels across it. The supervoid associated with the Cold Spot is not completely empty — it's not a vacuum, the researchers explain — but it possesses around 20 percent less material in it than any typical region of the universe. "Supervoids are not entirely empty, they're under-dense," says study co-author András Kovács of the Eötvös Loránd University in Budapest. This supervoid, located 3 billion light years from Earth — comparatively close in the cosmic scale of distances — was detected by analyzing data from the Pan-STARRS1 telescope located on Maui in Hawaii and from NASA's Wide Field Survey Explorer (WISE) satellite. The supervoid is unexpected given the usual even distribution of the universe at the scale the empty region occupies, the researchers say. "This is the greatest supervoid ever discovered," says Kovács. "In combination of size and emptiness, our supervoid is still a very rare event. We can only expect a few supervoids this big in the observable universe." While strongly suggesting an association between the supervoid and the Cold Spot, the new study hasn't completely proved a link, the researchers acknowledge, although they point out that two phenomena being in the same position in the sky by pure coincidence would seem unlikely. There's another issue; even if they are linked, the supervoid would only account for around 10 percent of the temperature decrease noted in the Cold Spot, experts say. "The void itself I'm not so unhappy about," says Carlos Frenk, a cosmologist at the University of Durham in Great Britain. "It's like the Everest of voids — there has to be one that's bigger than the rest. But it doesn't explain the whole Cold Spot, which we're still in the dark about."
Posted: 20 Apr 2015 08:26 PM PDT
Click to zoom
Posted: 20 Apr 2015 07:51 PM PDT
Posted: 20 Apr 2015 06:43 PM PDT
Click to zoom
Posted: 20 Apr 2015 06:28 PM PDT
Posted: 20 Apr 2015 06:04 PM PDT