Podcast Questions Show Light speed Andromeda Galaxy Dark Matter and Black Holes: related news

Podcast: Questions Show - Light speed, Andromeda Galaxy, Dark Matter and Black Holes

Another week, another roundup of your questions. This week listeners asked: will reaching light speed destroy the Universe? When is Andromeda going to look really, really cool with the unaided eye? Why didn't dark matter all turn into black holes? And there's even more. If you've got a question for the Astronomy Cast team, please email it in to info@astronomycast.com and we'll try to tackle it for a future show.

The Violent Variations of Black Holes

What is the environment around a black hole really like? Astronomers are getting a better idea by observing the light coming from the accretion disk surrounding black holes. The light is not constant — it flares, sputters and sparkles – and this flickering provides new and surprising insights into the colossal amount of energy emanating from around black holes. By mapping out how well the variations in visible light match those in X-rays on very short timescales, astronomers have shown that magnetic fields must play a crucial role in the way black holes swallow matter.

Even Early Galaxies Had Supermassive Black Holes

We're learning more about black holes and the early universe all the time, with the help of all the amazing ground-based telescopes astronomers now have at their disposal. Astronomers think that many - perhaps all - galaxies in the universe contain massive black holes at their centers. New observations with the Submillimeter Array now suggest that such colossal black holes were common even 12 billion years ago, when the universe was only 1.7 billion years old and galaxies were just beginning to form. The new conclusion comes from the discovery of two distant galaxies, both with black holes at their centers, which are involved in a spectacular collision.

Are We Close to Finding Dark Matter?

Scientists say he search for the mysterious substance which makes up most of the Universe could soon be at an end. A massive computer simulation was used to show the evolution of a galaxy like the Milky Way, and analysts were able to "see" gamma-rays given off by dark matter. Dark matter is believed to account for 85 per cent of the Universe's mass but has remained invisible to telescopes since scientists inferred its existence from its gravitational effects more than 75 years ago. If the computations are correct, the findings could help NASA's Fermi Telescope to search for the dark matter and open a new chapter in our understanding of the Universe.

Dark matter may shine with invisible 'dark light'

Mysterious dark matter could be shining with its own private kind of light. This "dark radiation" would be invisible to us, but could still have visible effects.

Dark Matter Discovered Near Solar System?

gpronger writes "The ATIC (Advanced Thin Ionization Calorimeter) has potentially discovered the presence of dark matter close (only 3000 light-years) to our solar system. The system detected a large amount of high energy cosmic rays which match the theoretical signature of dark matter annihilating itself. The universe is believed to be composed of about 25% dark matter, but there has been little evidence of it. This discovery, if correct, would be the first." The paper was published in Nature, but it requires a subscription to see beyond the abstract.

Violently Variable Black Holes Probed

Unique observations of the flickering light from the surroundings of two black holes provide new insights into the colossal energy that flows at their hearts. By mapping out how well the variations in visible light match those in X-rays on very short timescales, astronomers have shown that magnetic fields must play a crucial role in the way black holes swallow matter.

A Chance to See Dark Matter

Most of the matter in the universe is the mysterious dark matter, which astronomers can detect through gravitational effects but cannot actually see. The visible matter, or baryonic matter, that we're familiar with seems to make up only about 5% of the known universe compared to the 25% of dark matter!

VLT, Rossi Satellite Probe Variable Black Holes

Unique observations of the flickering light from the surroundings of two black holes provide new insights into the colossal energy that flows at their hearts. By mapping out how well the variations in visible light match those in X-rays on very short timescales, astronomers have shown that magnetic fields must play a crucial role in the way black holes swallow matter.

VLT and Rossi XTE satellite probe violently variable black holes

Unique observations of the flickering light from the surroundings of two black holes provide new insights into the colossal energy that flows at their hearts. By mapping out how well the variations in visible light match those in X-rays on very short timescales, astronomers have shown that magnetic fields must play a crucial role in the way black holes swallow matter.

Internet Retailer Conference wins award as fastest-growing show in U.S.

The Internet Retailer Conference and Exhibition has been recognized as the fastest-growing conference in the United States and Canada from 2005 to 2007 by Trade Show Week, the leading source of trade show industry news. Trade Show Week recognizes the fastest growing trade show, association show and consumer show. Internet Retailer was named the fastest growing trade show and the fastest growing show overall.

Black Holes May Not Grow Beyond Certain Limit

xyz writes "Do black holes increase in size indefinitely? According to an analysis by astronomers at Yale and the European Southern Observatory, the maximum size a black hole may reach is only few tens of billion of solar masses. The limit was calculated using an analysis of what may happen to the gas surrounding a black hole which has reached few tens of billions of solar masses. It is thought that black holes of such size heat the surrounding gas to a temperature where the radiation pressure begins blowing outer layers into space."

Where will new Fermi telescope find dark matter?

More than a billion particles were included in a simulation of dark matter in a Milky Way-like galaxy. The annihilation of dark matter in a cloud-like halo around the galaxy should produce a diffuse glow of gamma rays that could be detected by NASA's new Fermi telescope (Simulation: Virgo Consortium)

Black Silicon Discovery Could Change Digital Photography, Night Vision Forever

With the accidental discovery of "black silicon," Harvard physicists may have very well changed the digital photography, solar power and night vision industries forever. What is black silicon, you say? Well, it's just as it sounds. Black silicon. It's what this revolutionary new material does that's important, starting with light sensitivity. Early indications show black silicon is 100 to 500 times more sensitive to light than a traditional silicon wafer.

Black Holes Are The Rhythm At The Heart Of Galaxies

The powerful black holes at the center of massive galaxies and galaxy clusters act as hearts to the systems, pumping energy out at regular intervals to regulate the growth of the black holes themselves, as well as star formation, according to new data from NASA’s Chandra X-Ray Observatory.

Black Holes Are The Heart Of Galaxies

The powerful black holes at the center of massive galaxies and galaxy clusters act as hearts to the systems, pumping energy out at regular intervals to regulate the growth of the black holes themselves, as well as star formation, according to new data from NASA’s Chandra X-Ray Observatory.

Simulation points scientists to dark matter

This simulation shows the projected distribution of dark matter in the Milky Way. Myriad concentrations of dark matter are embedded within the galaxy's halo, and their dense centers emit energetic gamma rays from the annihilation of particles.

Space Dust Is Dark Matter

A small number of scientists defines space dust as the observable portion of dark matter. Space dust is comprised of small particles (about 0.1 mm) which reflect light on a very large scale. This is what can be seen of dark matter, not observable directly, but its hypothetical effects have been noticed.

The Whereabouts of Dark Matter Revealed

According to a Reuters article, a recent vast-scale simulation of the creation and evolution of a Milky Way-type of galaxy has indicated some potential places in space where scientists should search for dark matter. Although the existence of the matter that forms a huge part of the universe has been known for a long time, and theoretically proved, all efforts to actually discover it turned out to be useless. However, in light of their research, experts may yet stand a chance.

Simulations Predict Where We Can Find Dark Matter

p1234 writes with this excerpt from the Max Planck Institute for Astrophysics: "Simulations by the Virgo team show how the Milky Way's halo grew through a series of violent collisions and mergers from millions of much smaller clumps that emerged from the Big Bang. ... If Fermi does detect the predicted emission from the Milky Way's smooth inner halo, then it may, if we are lucky, also see gamma-rays from small (and otherwise invisible) clumps of dark matter which happen to lie particularly close to the Sun. ... The largest simulation took 3.5 million processor hours to complete. Volker Springel was responsible for shepherding the calculation through the machine and said: 'At times I thought it would never finish.' Max Planck Director, Professor Simon White, remarked that 'These calculations finally allow us to see what the dark matter dis

GALEX Spies a Ghost " And It's Alive!

Halloween means its time for ghost stories and here's a mysterious astronomical story about the "Ghost of Mirach." When viewed in visible light, as in the picture above on the left, the galaxy called NGC 404 appears as just a white blob. Mirach is a red giant star that looms large in visible light, hiding NGC 404 in its glare, and therefore was nicknamed "The Ghost of Mirach" But when the Galaxy Evolution Explorer (GALEX) spied the galaxy in ultraviolet light, a spooky ring materialized and the region came to "life." This ring, seen in blue in the picture on the right, contains new stars — a surprise considering that the galaxy was previously thought to be dead. "We thought this celestial ghost was essentially dead, but we've been able to show that it has an extended ring of new stars.

Anti-Matter Created By Laser At Livermore

zootropole alerts us to a press release issued today by Lawrence Livermore National Laboratory, announcing the production of 'billions of particles of anti-matter.' "Take a gold sample the size of the head of a push pin, shoot a laser through it, and suddenly more than 100 billion particles of anti-matter appear. The anti-matter, also known as positrons, shoots out of the target in a cone-shaped plasma 'jet.' This new ability to create a large number of positrons in a small laboratory opens the door to several fresh avenues of anti-matter research, including an understanding of the physics underlying various astrophysical phenomena such as black holes and gamma ray bursts." The press release doesn't characterize the laser used in this experiment, but it may have been this one.

New Program Connects Baltimore Students with Arts

black technology, black engineers, black education, black minorities, black engineer of the year awards (BEYA) and historically black colleges and universities (HBCU) from black community in US, UK, Caribbean and Africa. Find out more about your reader demographics, web-traffic, and valued added client services.

Podcast: Galactic Dust, the Speed of Photons, and the Big Bang Calculations

Another week, another roundup of your questions. This week listeners asked: what is galactic dust anyway, and where does it come from? Why can photons move at the speed of light? And how can astronomers know what happened right after the Big Bang? And there's even more. If you've got a question for the Astronomy Cast team, please email it in to info@astronomycast.com and we'll try to tackle it for a future show. Please include your location and a way to pronounce your name.

Colossal Black Holes Common In Early Universe, Spectacular Galactic Collision Suggests

Astronomers think that many - perhaps all - galaxies in the universe contain massive black holes at their centers. New observations with the Submillimeter Array now suggest that such colossal black holes were common even 12 billion years ago, when the universe was only 1.7 billion years old and galaxies were just beginning to form.

Search took 0.36 seconds.