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If the Universe is Structured Like a Block of Swiss Cheese, Then We Live Inside One of the Holes

06/13/2017 12:28AM

If the Universe is Structured Like a Block of Swiss Cheese, Then We Live Inside One of the Holes

A University of Wisconsin analysis has shown that our galaxy resides in an enormous void -- a region of space containing far fewer galaxies, stars, and planets than expected. This idea that we exist in one of the holes of the Swiss cheese structure of the cosmos helps explain inconsistencies in the measurement of the Hubble Constant, the unit that cosmologists use to describe the rate at which the universe is expanding. No matter what technique one uses, we should get the same value for the expansion rate of the universe, but we don't. The reason is that the void has far more matter outside, which exerts a larger gravitational pull towards the inside "wall" of the void. This affects the Hubble Constant value as measured from a technique that uses supernovae, while it has no effect on the value derived from a technique that uses the Cosmic Microwave Background.

Homo Sapiens Emerged 100,000 Years Earlier Than Previously Thought

06/09/2017 01:54AM

Homo Sapiens Emerged 100,000 Years Earlier Than Previously Thought

Researchers have uncovered 300,000 year old fossil bones of Homo Sapiens in Jebel Irhoud, Morocco -- a find that represents the oldest reliably dated fossil evidence of our species. The find is 100,000 years older than any other previously discovered Homo Sapiens fossils. Amazingly, the facial shape of the skulls is almost indistinguishable from that of modern humans living today. Previously, the oldest Homo Sapiens fossils were discovered at two sites in Ethiopia, dating 195,000 and 160,000 years old. Consequently, many researchers believed that all humans living today descended from the population that lived in East Africa around 200,000 years ago. But this new find suggests that early Homo Sapiens spread across the entire African continent and long before the out-of-Africa dispersal of Homo Sapiens began, there was dispersal within the African continent.

NASA's Juno Reveals an Amazing Side of Jupiter You've Never Seen

06/03/2017 05:30PM

NASA's Juno Reveals an Amazing Side of Jupiter You've Never Seen

NASA's Juno mission to Jupiter is the second spacecraft designed under its New Frontiers Program. The first was the New Horizons mission to Pluto, which flew by the small planet in July 2015 after a nine and a half year flight. Early science results from NASA's Juno mission to Jupiter portray the largest planet in our Solar System as a complex, gigantic, turbulent world, with Earth-sized polar cyclones, plunging storm systems that travel deep into the heart of the gas giant, and a mammoth, lumpy magnetic field. With its suite of science instruments, Juno will investigate the possible existence of a solid planetary core, map Jupiter's intense magnetic field, measure the amount of water and ammonia in the deep atmosphere, and observe the planet's auroras.

Large Hadron Collider Kicks Off the 2017 Season

05/31/2017 03:03AM

Large Hadron Collider Kicks Off the 2017 Season

Physicists at the Large Hadron Collider (LHC) have just kicked off the 2017 season. We left Season 2 with LHC providing collisions at the unprecedented energy of 13 TeV (Tera Electron Volts), almost double the collision energy of its Season 1 run that led to the discovery of the Higgs Boson. Operations for the new season are now re-starting with just a few proton bunches per beam, but the operators who control the most powerful collider in the world will soon increase the number of proton bunches and will also more tightly focus the size of the beams at the interaction points. In a few weeks, over a billion collisions will be produced every second at the heart of the experiments. In this new season, the LHC physicists plan to continue improving their knowledge of known phenomena while also probing the unknown.

Hypernova SN 2015L is the Brightest and Most Powerful Ever Seen

05/24/2017 12:30AM

Hypernova SN 2015L is the Brightest and Most Powerful Ever Seen

Records are made to be broken, as the expression goes, but rarely are records left so thoroughly in the dust. In 2015, stunned astronomers witnessed a cosmic explosion about 200 times more powerful than a typical Supernova event. At its peak intensity, SN 2015L exhibited 570 billion times the luminosity 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 in our Milky Way galaxy. This record breaking blast is thought to be an example of a Superluminous Supernova (or Hypernova), a recently discovered and supremely rare variety of explosion unleashed by certain stars when they die. Scientists are frankly at a loss to explain what sorts of stellar scenarios might be responsible for these types of extreme events.

115th Anniversary of the Discovery of the Antikythera Mechanism

05/17/2017 11:02PM

115th Anniversary of the Discovery of the Antikythera Mechanism

In 1900, an extraordinary mechanism was found by Greek sponge divers at the bottom of the sea near the island of Antikythera, situated between Crete and mainland Greece. Two years later, on May 17, 1902, Greek archaeologist Valerios Stais, discovered that this corroded chunk of metal pulled from the water was a rather fascinating technological artifact. It turned out to be part of the Antikythera Mechanism -- an ancient analog astronomical computer. For many decades, scientific investigation failed to yield much progress. However, research over the last 50 years has begun to reveal its secrets. The machine dates from around the end of the Second Century BC, and is the most sophisticated mechanism known from the ancient world. Nothing as complex was to be created by human hands for at least the next 1000 years.

So, Is a Brown Dwarf a Star... Or a Planet?

05/11/2017 02:57AM

So, Is a Brown Dwarf a Star... Or a Planet?

Smaller than stars, but bigger than giant planets, brown dwarfs are too small to sustain the hydrogen fusion process that fuels stars and allows them to remain hot and bright for a long period of time. So after formation, brown dwarfs slowly cool down and contract over time. The contraction usually ends after a few hundred million years, although the cooling is continuous. But sometimes, what is thought to be a brown dwarf is actually a planet -- or at least planet-like. A team at the Carnegie Institution for Science in Washington DC has discovered that what astronomers had previously thought was one of the closest brown dwarfs to our own Sun is in reality a Planetary Mass Object.

New Horizons is Already Halfway from Pluto to Its Next Flyby Target

05/06/2017 12:08AM

New Horizons is Already Halfway from Pluto to Its Next Flyby Target

Continuing on its path through the outer regions of the Solar System, NASA's New Horizons spacecraft has now traveled half the distance from Pluto, its storied first target, to 2014 MU69, the Kuiper Belt object (KBO) that it will fly past on January 1, 2019. The spacecraft reached that milestone on April 3, 2017 when it was 486.19 million miles (782.45 million kilometers) beyond Pluto -- the same distance to MU69. I suppose that when you're making history at 32,000 miles per hour, time moves faster and distances start to shrink.

Cassini Spacecraft Dives Between Saturn and Its Rings -- and Survives

04/30/2017 06:58PM

Cassini Spacecraft Dives Between Saturn and Its Rings -- and Survives

NASA's Cassini spacecraft is back in contact with Earth after its successful first-ever dive through the narrow gap between the planet Saturn and its rings on April 26, 2017. The spacecraft is in the process of beaming back science and engineering data collected during its passage. With this first dive, Cassini begins the "Grand Finale" of a remarkable mission that started in 1997. During this final chapter, Cassini will loop around Saturn approximately once per week, making a total of 22 dives between the rings and the planet. The spacecraft is now on a trajectory that will eventually plunge it into Saturn's atmosphere -- and end Cassini's mission -- on September 15, 2017.

Is It Time to Discard the Whole Dark Energy Contrivance?

04/23/2017 02:18AM

Is It Time to Discard the Whole Dark Energy Contrivance?

So what is Dark Energy? Well, the simple answer is that we don't know. It seems to contradict much of our understanding about the way we think the Universe works. The strangeness of Dark Energy is perplexing. It shows us that there is a gap in our knowledge that needs to be filled. But what if there is an alternative explanation for this enigmatic Dark Energy? What if it does not exist at all? That is what a Hungarian-American team of researchers is starting to conclude. They believe that they can explain the observed acceleration of the Universe without the need for Dark Energy. If their findings are upheld, it could have a significant impact on the direction of future research in physics.

NJIT's Big Bear Solar Observatory Develops Groundbreaking Next Generation of Adaptive Optics

04/18/2017 07:33PM

NJIT's Big Bear Solar Observatory Develops Groundbreaking Next Generation of Adaptive Optics

A groundbreaking new optical device, developed at New Jersey Institute of Technology's (NJIT) Big Bear Solar Observatory is designed to correct images of the Sun that are distorted by multiple layers of atmospheric turbulence. This next generation adaptive optics device is providing scientists with the most precisely detailed, real-time pictures to date of solar activity occurring across vast stretches of the Sun's surface.

A Look at SuperNova 1987A - Thirty Years Later

04/09/2017 02:25AM

A Look at SuperNova 1987A - Thirty Years Later

Three decades ago, astronomers spotted one of the brightest exploding stars in more than 400 years. The titanic supernova, called Supernova 1987A (SN 1987A), blazed with the power of 100 million suns for several months following its discovery on February 23, 1987. Since that first sighting, SN 1987A has continued to fascinate astronomers with its spectacular light show. Located in the nearby Large Magellanic Cloud, it was the nearest supernova explosion observed in hundreds of years and provided the best opportunity yet for astronomers to study the phases before, during, and after the death of a star. Recent data from the Hubble Space Telescope, the Chandra X-ray Observatory, and the Atacama Large Millimeter-Submillimeter Array (ALMA) indicates that SN 1987A has passed an important threshold as the supernova shock wave blasts through the dense ring of gas initially expelled by the pre-supernova star.

Villanova Astronomers Discover a New Class of Pulsating X-Ray Stars

03/29/2017 08:34PM

Villanova Astronomers Discover a New Class of Pulsating X-Ray Stars

A surprising new class of X-ray pulsating variable stars has been discovered by a team of Villanova University astronomers. New X-ray observations obtained by NASA's Chandra X-ray Observatory reveal that the star known as "d Cephei," the bright prototype of all Classical Cepheids, is actually a periodic pulsed X-ray source. At a distance of 890 light years away, this star, after which all Cepheids are named, is also one of the closest. Cepheids are among the most astronomically important objects in the Universe, for by measuring the pulsation periods and brightness of Cepheids, astronomers can measure distances to other galaxies.

Mapping the Family Tree of Stars

03/21/2017 04:36PM

Mapping the Family Tree of Stars

Astronomers are borrowing principles applied in biology and archaeology to build a family tree of the stars in our galaxy. By studying chemical signatures found in the stars, they are piecing together evolutionary trees looking at how the stars formed and how they are connected to each other. The signatures act as a proxy for DNA sequences. It's akin to chemical tagging of stars and forms the basis of a discipline astronomers refer to as Galactic Archaeology.

Maybe the World Really is Flat -- Do We Live in a Holographic Universe?

03/04/2017 05:04PM

Maybe the World Really is Flat -- Do We Live in a Holographic Universe?

The holographic universe, an idea first suggested in the 1990s, is one where all the information that makes up our 3D "reality" (plus time) is contained on a 2D surface. The idea is similar to that of an ordinary hologram on a credit card, where a three dimensional image is encoded on the two dimensional card. A team of UK, Canadian, and Italian theoretical physicists have now provided what is believed to be the first observational evidence that our universe could indeed be a vast and complex hologram. They have found substantial evidence supporting a holographic explanation of the universe -- In fact, as much evidence as currently exists for traditional explanations based on the widely accepted theory of cosmic inflation.