Earth (Usually) Has Two Moons
So reports MIT’s Technology Review:
Back in 2006, the Catalina Sky Survey in Arizona noticed that a mysterious body had begun orbiting the Earth. This object had a spectrum that was remarkably similar to the titanium white paint used on Saturn V rocket stages and, indeed, a number of rocket stages are known to orbit the Sun close to Earth.
But this was not an object of ours. Instead, 2006 RH120, as it became known, turned out to be a tiny asteroid just a few metres across–a natural satellite like the Moon. It was captured by Earth’s gravity in September 2006 and orbited us until June 2007 when it wandered off into the Solar System in search of a more interesting neighbour.
2006 RH120 was the first reliably documented example of a temporary moon …
A Cloaked UFO Next To Mercury?
Many who want to believe are claiming that this footage taken by NASA’s STEREO spacecraft shows a “cloaked” UFO appearing, and then disappearing, near the planet Mercury. Extraterrestrials on vacation?
Our Milky Way Galaxy Devours Its Small Neighboring Galaxies
Via PhysOrg:
A team of astronomers led by Sergey Koposov and Vasily Belokurov of Cambridge University recently discovered two streams of stars in the Southern Galactic hemisphere [of the Milky Way] that were torn off the Sagittarius dwarf galaxy. This discovery came from analysing data from the latest Sloan Digital Sky Survey (SDSS-III) and was announced in a paper released that connects these new streams with two previously known streams in the Northern Galactic hemisphere.
“We have long known that when small dwarf galaxies fall into bigger galaxies, elongated streams, or tails, of stars are pulled out of the dwarf by the enormous tidal field,” said Sergey Koposov.
The Sagittarius dwarf galaxy used to be one of the brightest of the Milky Way satellites. Its disrupted remnant now lies on the other side of the Galaxy, breaking up as it is crushed and stretched by huge tidal forces. It is so small that…
Large Asteroid 2005 YU55 to Pass Earth — Closer Than Moon
Edward Lovett and Ned Potter Report on ABC News:
We have a visitor — a large asteroid called 2005 YU55 that is expected to come within approximately 201,700 miles of Earth on Tuesday, according to NASA. That’s slightly less than the distance from Earth to the moon.
Asteroids often pass this close, but most are tiny. Countless thousands of pieces come plunging into the atmosphere, but they burn up without doing any harm. If they’re as large as grains of sand, we may, if we’re lucky, see them in the night sky as shooting stars.
But 2005 YU55 is at least 1,300 feet wide — larger than an aircraft carrier, according to radar measurements. The last time an asteroid this big passed by was in 1976, and the next one scientists know of won’t be until 2028, NASA says. (There have been some rude surprises in between, but not involving anything remotely as…
The Largest Galaxy Clusters in the Universe Hint That Something is Behaving Strangely
Via the Daily Galaxy:
The large-scale structure of the Universe appears to be dominated by vast “hyperclusters” of galaxies, according to the new the Sloan Digital Sky Survey, compiled with a telescope at Apache Point, New Mexico. The survey plots the 2D positions of galaxies across a quarter of the sky. The science team has concluded that it could mean that gravity or dark energy — or something completely unknown — is behaving very strangely.
We know that the universe was smooth just after its birth. Measurements of the cosmic microwave background radiation (CMB), the light emitted 370,000 light years after the big bang, reveal only very slight variations in density from place to place. Gravity then took hold and amplified these variations into today’s galaxies and galaxy clusters, which in turn are arranged into big strings and knots called superclusters, with relatively empty voids in between.
On even larger scales, though, cosmological…
In 1883, Did Earth Narrowly Miss Comet That Would Have Destroyed All Life?
“If they had collided with Earth we would have had 3275 Tunguska events in two days, probably an extinction event.”
The biggest event which never happened and no one knows about? Offering a novel reinterpretation of some forgotten historical data, several Mexican researchers say a billion-ton comet may have passed a few hundred miles from Earth in 1883. Via Technology Review:
On 12th and 13th August 1883, an astronomer at a small observatory in Zacatecas in Mexico made an extraordinary observation. José Bonilla counted some 450 objects, each surrounded by a kind of mist, passing across the face of the Sun.
Bonilla published his account of this event in a French journal called L’Astronomie in 1886. Today, Hector Manterola at the National Autonomous University of Mexico in Mexico City, and a couple of pals, think that Bonilla must have been seeing fragments of a comet that had recently broken up. This explains the…
Microbes Found Preadapted for Life in Space
Via the Daily Galaxy (some have been unable to get this link, here is the cached version):
Microbes born on Earth are already pre-adapted for journeying through space, living in space, and not just surviving but flourishing in radioactive environments where they are continually exposed to radiation by ions similar to what might be encountered in a nebular cloud.
In 1958, physicists discovered clouds of bacteria, ranging from two million bacteria per cm3 and over 1 billion per quart, thriving in pools of radioactive waste directly exposed to ionizing radiation and radiation levels millions of times greater than could have ever before been experienced on this plane.
The world’s first artificial nuclear reactor was not even built until 1942. Prior to the 1945, poisonous pools of radioactive waste did not even exist on Earth. And yet, over a dozen different species of microbe have inherited the genes which enable them to survive conditions which…
Time Reversal: A Simple Particle Could Reveal New Physics
Shelley Littin writes in Space Daily:
A simple atomic nucleus could reveal properties associated with the mysterious phenomenon known as time reversal and lead to an explanation for one of the greatest mysteries of physics: the imbalance of matter and antimatter in the universe.
The physics world was rocked recently by the news that a class of subatomic particles known as neutrinos may have broken the speed of light.
Adding to the rash of new ideas, University of Arizona theoretical physicist Bira van Kolck recently proposed that experiments with another small particle called a deuteron could lead to an explanation for one of the most daunting puzzles physicists face: the imbalance of matter and antimatter in the universe. A deuteron is a simple atomic nucleus, or the core of an atom. Its simplicity makes it one of the best objects for experiments in nuclear physics …
2011 Nobel Prize to Dark Energy: Explained (Video)
Guest narrator Sean Carroll of Caltech describes dark energy and the acceleration of the universe, the discovery of which was awarded the 2011 Nobel Prize in Physics on October 4th, from Minute Physics’ YouTube:
Lunar Orbiter Find Footprints On The Moon
Some people were in awe as they watched to first men walk on the moon in 1969. Others still remain in skepticism of the lunar landing. Taken by NASA’s lunar orbiter, new photographs have been released of landing sites, including footprints left on the surface. Via Reuters:
Astronomers Find Planet Made Of Diamond
What celebrity couple will be first to take a honeymoon on the planet made of solid diamond crystal? Via Wired Science:
An international team of astronomers, led by Australia’s Swinburne University of Technology professor Matthew Bailes, has discovered a planet made of diamond crystals, in our own Milky Way galaxy.
The planet is relatively small at around 60,000 km in diameter (still, it’s five times the size of Earth). But despite its diminutive stature, this crystal space rock has more mass than the solar system’s gas giant Jupiter.
Researchers from institutions in the UK, Australia, Germany, Italy and the USA used a variety of radio telescopes — including the Australian Parkes CSIRO, the Lovell in Cheshire and the Keck in Hawaii — and 200,000 Gigabytes of celestial data to find the nifty diamond-esque planet.
DARPA Wants To Send Humans To The Stars
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Is this a good way to spend the money we’re borrowing from Chinese investors in U.S. Government debt? The New York Times‘ Dennis Overbye reports on DARPA’s bold step:
Alpha Centauri or bust.
The government agency that helped invent the Internet now wants to do the same for travel to the stars.
In what is perhaps the ultimate startup opportunity, Darpa, the Defense Advanced Research Projects Agency, plans to award some lucky, ambitious and star-struck organization roughly $500,000 in seed money to begin studying what it would take — organizationally, technically, sociologically and ethically — to send humans to another star, a challenge of such magnitude that the study alone could take a hundred years.
The awarding of that grant, on Nov. 11 — 11/11/11 — is planned as the culmination of a yearlong Darpa-NASA effort called the 100-Year Starship Study, which started quietly last winter and will include a three-day public symposium in…
Neil deGrasse Tyson: Why Did We Stop Dreaming About Outer Space? (Video)
Astrophysicist and NOVA host Neil deGrasse Tyson laments the United States’ failure of imagination with its space program, from a recent episode of Real Time with Bill Maher:
How The Universe (Something) Appeared From Nothing (Video)
Granted this video is a promo for the New Scientist’s recent issue on “existence”, it’s pretty interesting, if you are OK with incomplete answers. (Figuring out how the universe got so large is still a serious head-scratcher.) My takeaway after watching this, is if “something” is not really that different from “nothing” (according to our human perception) then, well, there is still much to ponder …
‘Multiverse’ Theory Suggested By Microwave Background
“It would be a pretty amazing thing to show that we have actually made physical contact in another universe. It’s a long shot, but it would by very profound for physics” (Prof. Efstathiou). Via BBC:
The idea that other universes – as well as our own – lie within “bubbles” of space and time has received a boost.
Studies of the low-temperature glow left from the Big Bang suggest that several of these “bubble universes” may have left marks on our own.
This “multiverse” idea is popular in modern physics, but experimental tests have been hard to come by.
The preliminary work, to be published in Physical Review D, will be firmed up using data from the Planck telescope.
For now, the team has worked with seven years’ worth of data from the Wilkinson Microwave Anisotropy Probe, which measures in minute detail the cosmic microwave background (CMB) – the faint glow left from our Universe’s…
Black Hole Hosts Universe’s Most Massive Water Cloud
Photo: NASA
A giant quasar billions of light-years away is surrounded by water vapor that could fill Earth’s oceans over 140 trillion times. Via National Geographic:
In a galaxy 12 billion light-years away resides the most distant and most massive cloud of water yet seen in the universe, astronomers say.
Weighing in at 40 billion times the mass of Earth, the giant cloud of mist swaddles a type of actively feeding supermassive black hole known as a quasar.
Among the brightest and most energetic objects in the universe, quasars are black holes at the centers of galaxies that are gravitationally consuming surrounding disks of material while burping back out powerful energy jets.
“As this disk of material is consumed by the central black hole, it releases energy in the form of x-ray and infrared radiation, which in turn can heat the surrounding material, resulting in the observed water vapor,” said study co-author Eric Murphy, an astronomer with…
Planet Earth Has A Stalker
Michael Reilly reports in the New Scientist:
An asteroid 300 metres in diameter is stalking the Earth. Hiding in the pre-dawn twilight, it has marched in lockstep with our planet for years, all but invisible to our telescopes.
The rock is Earth’s first confirmed Trojan, which can orbit the sun in either of two gravitational wells along the same orbital path as our planet. From the sun’s point of view, these wells lie 60 degrees ahead of and behind the Earth, at Lagrange points where gravitational forces between the sun and the Earth balance out.
Trojans are common — Jupiter alone boasts about 5000, and Neptune and Mars each have their own smaller collections. But finding Earth’s has proven difficult, because the Lagrange points lie towards the sun in the sky. Astronomers must look for the objects just before the sun rises or after it sets, and until now the glare of this…
This is Planet Earth’s Impact So Far in the Universe
Look for the tiny blue dot for our impact. Adam Grossman writes about “The Tiny Humanity Bubble” on jackadamblog:
Mankind has been broadcasting radio waves into deep space for about a hundred years now — since the days of Marconi.
That, of course, means there is an ever-expanding bubble announcing Humanity’s presence to anyone listening in the Milky Way. This bubble is astronomically large (literally), and currently spans approximately 200 light years across.
But how big is this, really, compared to the size of the Galaxy in which we live (which is, itself, just one of countless billions of galaxies in the observable universe)?
How Buzz Aldrin Answers Moon Landing Conspiracy Theorists (Video)
42 years ago today Buzz Aldrin landed on the Moon, and Buzz doesn’t enjoy anyone saying otherwise:
Here’s more on what got Buzz so worked up.
