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News

President Trump In Office for a Month -- Pluto May Be Reinstated as a Planet

02/24/2017 09:59PM

President Trump In Office for a Month -- Pluto May Be Reinstated as a Planet

First of all, I must apologize for the deliberately provocative and over-hyped title for this News Item. I got all wrapped-up in the sensationalism surrounding any mention of our new President Trump and I just couldn't resist. FACT #1 - President Trump has been in office for about a month. FACT #2 - Some scientists (including some prominent NASA scientists) are proposing a new definition for "Planet" that would reinstate Pluto as a planet. What I deliberately left out of the title is FACT #3 - The two statements are totally unrelated to each other. But face it -- You are reading this because you fell for a cheap trick referred to as a "Post-Hoc Fallacy," where you as a reader infer a cause and effect for two facts simply because they occurred about the same time and are presented together. But enough of this -- Back to the News Item. If this new definition is accepted by the IAU, then Pluto may once again be a planet.

Could Intermediate-Mass Black Holes Lurking in Galactic Halos Account for Dark Matter? Probably Not

02/20/2017 12:24AM

Could Intermediate-Mass Black Holes Lurking in Galactic Halos Account for Dark Matter?  Probably Not

The nature of dark matter has long been questioned, but the recent discovery of gravitational waves by the Laser Interferometer Gravitational-Wave Observatory (LIGO) has renewed interest in the possibility that dark matter could actually consist of primordial black holes in the mass range of 10 to 1000 solar masses. Could dark matter be made of these intermediate-mass black holes that formed at the beginning of the Universe? A recent study takes a new look at this question and concludes... Probably not.

Stray Black Hole "Bullet" Zipping Through the Milky Way

02/08/2017 11:59PM

Stray Black Hole "Bullet" Zipping Through the Milky Way

By analyzing the gas motion of an extraordinarily fast moving cosmic cloud in a corner of the Milky Way, astronomers have detected hints of a wandering black hole hidden in the cloud. Millions of lone black holes are believed to be zipping through the Milky Way, although only a few dozen have been found to date.

Newly Discovered Dipole Repeller is Pushing Our Local Group of Galaxies Through Space

02/02/2017 09:42PM

Newly Discovered Dipole Repeller is Pushing Our Local Group of Galaxies Through Space

For decades, astronomers have known that our Milky Way galaxy, together with our companion Andromeda galaxy, are moving through space at about 1.4 million miles per hour. Scientists have generally assumed that excessive gravity from two dense regions of the universe, known as the Great Attractor and the Shapley Concentration, were responsible for this motion. But now, in a groundbreaking study, a team of researchers is reporting the discovery of a previously unknown and nearly empty region of space located in the opposite direction that is effectively exerting a repelling force and pushing our Local Group of galaxies through space. This void has been dubbed the "Dipole Repeller."

Roger Chaffee, Ed White, Gus Grissom -- 50 Years Ago Today

01/27/2017 05:05PM

Roger Chaffee, Ed White, Gus Grissom -- 50 Years Ago Today

It was 50 years ago today -- January 27, 1967, when tragedy struck on the launch pad at Cape Kennedy during a pre-flight test for Apollo 1. The mission was to be the first crewed flight of Apollo, and was scheduled to launch on February 21, 1967. Astronauts Virgil "Gus" Grissom, Edward White, and Roger Chaffee lost their lives when a fire swept through the Apollo Command Module.

Is This the First Sign of a Weird Quantum Property of Empty Space?

01/27/2017 12:00AM

Is This the First Sign of a Weird Quantum Property of Empty Space?

Neutron stars are the very dense remnant cores of massive stars that have exploded as supernovae at the ends of their lives. They have extreme magnetic fields that are billions of times stronger than that of the Sun. By studying the light emitted from an extraordinarily dense and strongly magnetized neutron star using ESO's Very Large Telescope (VLT), astronomers may have found the first observational indications of a strange quantum effect first predicted by Werner Heisenberg and Hans Heinrich Euler in the 1930s. The polarization of the observed light suggests that the empty space around the neutron star is subject to a quantum effect known as "Vacuum Birefringence," which results from the interaction between photons and virtual charged particles that appear and vanish all the time due to quantum mechanics.

Why are Quasars so Bright? - - Russian RadioAstron Space Telescope and Arecibo Link Together to Find an Answer

01/22/2017 08:50PM

Why are Quasars so Bright? - - Russian RadioAstron Space Telescope and Arecibo Link Together to Find an Answer

Remarkable new observations derived by linking Arecibo Observatory's 305 meter dish with Russia's RadioAstron Space Radio Telescope has provided results that are causing much head scratching in radio astronomical circles. The achievable resolution from this combination of observatories is equivalent to seeing a golf ball on the Moon or a fingernail on the surface of the Earth from a spy satellite in geosynchronous orbit. What used to be a well understood explanation for the mechanism that generates intense radio signals from tiny and very distant quasar nuclei has now been tested in previously impossible ways. The results make it difficult to interpret the data in terms of conventional theories.

Some Words of Wisdom -- My Favorite Quotable Quotes

01/05/2017 04:47AM

Some Words of Wisdom -- My Favorite Quotable Quotes

Let's start off the new year with some words of wisdom. Here is an update to my collection of quotable quotes. Some are deep. Others not so much...

Solving Five Problems of Particle Physics and Cosomolgy in One Stroke

12/09/2016 05:32PM

Solving Five Problems of Particle Physics and Cosomolgy in One Stroke

In the search for the mysterious dark matter, physicists have used elaborate computer calculations to come up with an outline of the particles of this unknown form of matter. To do this, the scientists extended the successful Standard Model of particle physics, which allowed them, among other things, to predict the mass of so-called axions, promising candidates for dark matter that could be up to ten billion times lighter than electrons. Through a simple extension to the Standard Model (by adding just three neutrinos, a fermion, and a field that includes two new particles), physicists have come up with a new twist that they say solves five of the biggest unanswered questions in modern physics all at once: explaining the weirdness of dark matter, neutrino oscillations, baryogenesis, cosmic inflation, and the strong CP (Charge Parity) problem.

A Major Supercluster of Galaxies is Hiding Behind the Milky Way

11/23/2016 02:57PM

A Major Supercluster of Galaxies is Hiding Behind the Milky Way

Superclusters are the largest and most massive known structures in the Universe. They consist of clusters of galaxies that span up to 200 million light years across the sky. The most famous supercluster is the Shapley Supercluster, some 650 million light years away. It is believed to be the largest of its kind in our cosmic neighborhood. Now a team of astronomers has discovered a previously unknown major concentration of galaxies hiding behind our Milky Way Galaxy in the constellation Vela, which they have dubbed the Vela Supercluster. The gravitational attraction from this large mass concentration in our cosmic neighborhood may have an important effect on the motion of our Local Group of galaxies.

Funnels on Mars Could Be the Place to Look for Life

11/14/2016 03:25PM

Funnels on Mars Could Be the Place to Look for Life

Strangely shaped depressions on Mars could be new places to look for signs of life on the Red Planet, according to a study at the University of Texas - Austin. The depressions were probably formed by volcanos beneath glaciers and could provide a warm, chemical-rich environment well suited for microbial life. These are similar in many ways to "ice cauldrons" on Earth -- formations found in Iceland and Greenland that are made by volcanos erupting under sheets of ice.

Mark Your Calendar -- "Super Moon" of November 14th Will Be the Largest Since 1948

11/06/2016 12:46AM

Mark Your Calendar -- "Super Moon" of November 14th Will Be the Largest Since 1948

The full Moon has a reputation for trouble. It raises high tides, it makes dogs howl, it wakes you up in the middle of the night with beams of moonlight stealing through drapes. If a moonbeam wakes you up on the night of November 14th, 2016, you might want to get out of bed and take a look. This full Moon is a "Super Moon," and there is something particularly noteworthy about it -- During the moment of perigee, the centers of the Earth and Moon will be only 221,524 miles apart. That is the closest approach of the Moon to the Earth in over 68 years. Moreover, there will not be a closer approach for another 18 years -- November 25, 2034.

Observable Universe Contains Ten Times More Galaxies Than Previously Thought

10/27/2016 01:35PM

Observable Universe Contains Ten Times More Galaxies Than Previously Thought

The universe suddenly looks a lot more crowded, thanks to a deep-sky census assembled from surveys taken by the Hubble Space Telescope and other observatories. One of the most fundamental questions in astronomy is: "How many galaxies does the universe contain." The landmark Hubble Deep Field, taken in the mid-1990s, gave the first real insight into the universe's galaxy population. Subsequent sensitive observations such as Hubble's Ultra Deep Field revealed a myriad of even more faint galaxies. This led to an estimate that the observable universe contained about 200 billion galaxies. The new research shows that this estimate is too low and comes to the staggering conclusion that at least 10 times more galaxies exist in the observable universe than astronomers thought.

Is It Time to Discard the Whole Dark Matter Contrivance?

10/14/2016 04:12PM

Is It Time to Discard the Whole Dark Matter Contrivance?

In the late 1970s, astronomers Vera Rubin and Albert Bosma independently found that spiral galaxies rotate at a nearly constant speed. The velocity of the stars and gas inside a galaxy does not decrease with the radius, as one would expect from Newton's laws and the distribution of visible matter. Rather, it remains approximately constant. For lack of a better explanation, such "flat rotation curves" have generally been attributed to a mysterious, invisible, and still undetected dark matter surrounding these galaxies, which provides the additional gravitational attraction required to balance everything out. Now a team led by Case Western Reserve University researchers has found a significant new relationship in spiral and irregular galaxies -- The acceleration observed in rotation curves tightly correlates with the gravitational acceleration expected from the visible mass only. This new work challenges the current understanding (and possibly even the existence) of dark matter.

Our Galaxy's Most Mysterious Star is Even Stranger Than We Thought

10/03/2016 07:36PM

Our Galaxy's Most Mysterious Star is Even Stranger Than We Thought

A star known by the unassuming name of KIC 8462852 in the constellation Cygnus has been raising eyebrows in the scientific community for the past year. In 2015 a team of astronomers announced that the star underwent a series of very brief, non-periodic dimming events while it was being monitored by NASA's Kepler space telescope, and no one could quite figure out what was going on. A new study from the Carnegie Institution of Washington and Caltech has now deepened the mystery.