Free Republic

Astronomers have detected a signal from the first stars as they appeared and illuminated the universe, in observations that have been hailed as “revolutionary”.

In a clean room inside a clean room at NASA’s Kennedy Space Center, a petite telescope is perched on a stand for a final series of checkouts prior to launch. The extra fastidiousness is because the observatory’s four cameras will fly without protective covers—one of several simplifying design decisions made to help ensure the Transiting Exoplanet Survey Satellite, or TESS, will meet its goal of measuring the masses of at least 50 small, rocky and potentially Earth-like worlds as part of the first all-sky, exoplanet survey. TESS was proposed even before NASA’s planet-hunting Kepler space telescope, launched in 2009, demonstrated...

Physicists have insisted for a long time that black holes are impenetrable ciphers. Whatever goes in is lost, impossible to study or meaningfully understand. Some small amount of matter and energy might escape a black hole in the form of "Hawking radiation," but anything still inside the black hole is functionally disappeared from the physical universe. The idea is a basic premise of modern physics: If something falls into a black hole, it can't be contacted, it's future can't be predicted. No observer could possibly survive traveling into the dark space, not even long enough to glance around and notice...

314 Action Wants to Elect Scientists, But Only if They're Democrats The U.S. Congress is made up mostly of professional politicians and lawyers. This comes as a surprise to precisely no one, but the sheer numbers are rather striking.According to the Congressional Research Service (PDF, Table 2), the 115th Congress consists of 168 Representatives (out of 435) who are lawyers, and the Senate has 50 lawyers (out of 100). Combined, lawyers make up nearly 41% of Congress.How many lawyers are in the U.S.? One law firm (with a nifty interactive map!) estimates roughly 1.3 million. Given that the U.S. population...

Researchers create a hyperbolic metasurface on which light propagates with completely reshaped wafefronts Light waves usually disperse in cirular or convex wavefronts form, like ripples on water surface created by a stone. But now researchers have found that it is possible to alter light's wavefronts and to give them a completely new shape. To observe the waves as they propagate along the metasurface, researcher created a surface based on boron nitride. The material was selected because it has the ability to manipulate infrared light on extremely small length scales and it requires an extremely precise structuring on the nanometer scale...

(The Hubble Space Telescope captured this image of ancient and brilliant quasar 3C 273, which resides in a giant elliptical galaxy in the constellation of Virgo. Its light has taken some 2.5 billion years to reach us. Despite this great distance, it is still one of the closest quasars to our home. It was the first quasar ever to be identified, and was discovered in the early 1960s by astronomer Allan Sandage.) Shining so brightly that they eclipse the ancient galaxies that contain them, quasars are distant objects powered by black holes a billion times as massive as our...

It's time to gaze into our crystal ball and see what the coming year has in store for science. From powerful new rockets and asteroid-sampling spacecraft to groundbreaking particle physics, there's plenty to look forward to in 2018. Aeronautics and space exploration A new tool to find exoplanets In March 2018, NASA will launch its Transiting Exoplanet Survey Satellite (TESS) - a mission to find previously undiscovered exoplanets from the vantage point of low Earth orbit. The space-based telescope is expected to discover thousands of exoplanets over the next several years as it measures the luminosity of more than 200,000...

Aluminium oxynitride or AlON is a ceramic composed of aluminium, oxygen and nitrogen. It is marketed under the name ALON by Surmet Corporation. AlON is optically transparent (≥80%) in the near-ultraviolet, visible and midwave-infrared regions of the electromagnetic spectrum. It is 4 times harder than fused silica glass, 85% as hard as sapphire, and nearly 15% harder than magnesium aluminate spinel. Since it has a cubic spinel structure, it can be fabricated to transparent windows, plates, domes, rods, tubes and other forms using conventional ceramic powder processing techniques. ALON is the hardest polycrystalline transparent ceramic available commercially. Combination of optical...

Photo/Illustraion Japanese researchers have developed a light-emitting device that floats like a firefly and could lead to the creation of mid-air displays and other contraptions. The developers include Yoshihiro Kawahara and Makoto Takamiya, both associate professors with the University of Tokyo, and Yasuaki Kakehi, an associate professor with Keio University. The hemispherical device, with an embedded light-emitting diode, measures 4 millimeters across and weighs 16 milligrams. It can levitate and roam in mid-air when ultrasound beams are applied. The researchers reduced its weight by using a custom-made integrated circuit and by drawing on the technology of wireless powering, or remote...

In new experiments, however, the physicists coaxed individual photons to cozy up to each other and link, similar to the way individual atoms stick together in molecules. The photon dance happens in a lab at MIT where the physicists run table-top experiments with lasers. Cantu, his colleague Aditya Venkatramani, a Ph.D. candidate in atomic physics at Harvard University, and their collaborators start by creating a cloud of chilled rubidium atoms. Rubidium is an alkali metal so it typically looks like a silver-white solid. But vaporizing rubidium with a laser and keeping it ultracold creates a cloud the researchers contain in...

The most massive galaxies in our neighbourhood formed their stars billions of years ago, early in the history of the universe. At the present day, they produce very few new stars. Astronomers have long believed that is because they contain very little gas – a key ingredient necessary to produce stars. But our new study, published in Nature Astronomy, is now challenging this long held view. Through probing the extreme environments of faraway massive galaxies, we can learn not only about their evolution and the history of the universe, but most importantly about the fundamental processes regulating the formation of...

[T]he study of GRBs have been complicated by two major issues. On the one hand, GRBs are very short lived, lasting for only seconds at a time. Second, all detected events have occurred in distant galaxies, some of which were billions of light-years away. Nevertheless, there are a few theories as to what could account for them, ranging from the formation of black holes and collisions between neutron stars to extra-terrestrial communications. ... With the assistance of their collaborators in the US, France, the UK and Sweden, the team from Queen’s University Belfast relied on the Gemini laser, located at...

These remaining cores of dead stars can only get so massive before they become black holes. _______________________________________________________________________________________________________________________________________ The subtle difference between when a massive dying star compresses into a core and when it collapses entirely may have been found. In a study published in Astrophysical Journal Letters, researchers at the Goethe University in Frankfurt say they’ve found the dividing line between compact objects called neutron stars and black holes. When a massive star reaches the end of its life, it goes out with an immense bang called a supernova. From there, one of two known things Can happen: it either...

Observations of a trio of dead stars have confirmed that a foundation of Einstein’s gravitational theory holds even for ultradense objects with strong gravitational fields. The complex orbital dance of the three former stars conforms to a rule known as the strong equivalence principle, researchers reported January 10 at a meeting of the American Astronomical Society. That agreement limits theories that predict Einstein’s theory, general relativity, should fail at some level. According to general relativity, an object’s composition has no impact on how gravity pulls on it: Earth’s gravity accelerates a sphere of iron at the same rate as a...

[T]ime has often been considered as the fourth dimension of space, with three spatial dimensions where one can go up or down, left or right, or forward or backward. But two new papers published in the journal Nature suggest that there might be a fourth spatial dimension, one that could possibly suggest previously undiscovered directions of motion. As detailed in a report from Gizmodo, two separate teams of researchers created their own two-dimensional setups, with one team using ultra-cold atoms and the other one working with waves of light. While the studies produced varying results, the findings complemented each other,...

A laser-driven technique for creating fusion that dispenses with the need for radioactive fuel elements and leaves no toxic radioactive waste is now within reach, say researchers. Dramatic advances in powerful, high-intensity lasers are making it viable for scientists to pursue what was once thought impossible: creating fusion energy based on hydrogen-boron reactions. And an Australian physicist is in the lead, armed with a patented design and working with international collaborators on the remaining scientific challenges. In a paper in the scientific journal Laser and Particle Beams today, lead author Heinrich Hora from the University of New South Wales in...

We're about to see — for the very first time — the event horizon of a black hole, proving beyond any last vestige of doubt that Einstein’s interstellar monsters are real. And here’s what it will look like.

Up for Grabs In Science, When 'Anything Goes,' Everything Goesby Denyse O'Leary Family values activist Austin Ruse's new book, Fake Science: Exposing the Left's Skewed Statistics, Fuzzy Facts, and Dodgy Data (Regnery, 2017), offers a look at a world growing increasingly hostile to evidence-based reasoning. We have not discovered better reasoning methods; rather, many people seem to have decided that reasoning is not relevant to our life together, and perhaps not relevant to the life of the mind generally. Ruse begins his book with a note about polls. Opinion pollsters claim that their work is a scientific enterprise. But in...

Black holes are famous for their muscle: an intense gravitational pull known to gobble up entire stars and launch streams of matter into space at almost the speed of light. It turns out the reality may not live up to the hype. In a paper published today in the journal Science, University of Florida scientists have discovered these tears in the fabric of the universe have significantly weaker magnetic fields than previously thought. A 40-mile-wide black hole 8,000 light years from Earth named V404 Cygni yielded the first precise measurements of the magnetic field that surrounds the deepest wells of...

Japanese netizens help scan lightning for gamma rays Japan -- A storm system approaches: the sky darkens, and the low rumble of thunder echoes from the horizon. Then without warning... Flash! Crash! -- lightning has struck. This scene, while familiar to anyone and repeated constantly across the planet, is not without a feeling of mystery. But now that mystery has deepened, with the discovery that lightning can result in matter-antimatter annihilation. In a collaborative study appearing in Nature, researchers from Japan describe how gamma rays from lightning react with the air to produce radioisotopes and even positrons -- the antimatter...