Supermassive Black Holes Can’t Swallow Dark Matter

A modelled accretion disk around a black hole. Image credit: Michael Owen, John Blondin (North Carolina State Univ.). Source: http://apod.nasa.gov/apod/ap050312.html

Apparently, black holes and dark matter don’t play well together. Broadly speaking, black holes can be considered to be a significant portion of the “missing mass” in the universe, but dark matter is distinguished as “non-baryonic matter”. It seems that this mysterious non-baryonic matter is being used to explain a huge number of unexplained cosmic mysteries, but in the case of supermassive black holes, dark matter plays a very small role insofar as being used as black hole food…
Continue reading “Supermassive Black Holes Can’t Swallow Dark Matter”

Could Mars Quakes, Seasonal Temperature Changes or a Chance Meteorite Impact Cause Mars Avalanches?

Detailed view of one of the avalanches observed by the HiRISE instrument in the Mars North Pole region. Image credit: NASA/JPL/UA

It doesn’t get much better than this. A robotic orbiter snaps a photo hundreds of miles above the surface of an alien planet, capturing a geological event as it happens. Yes, we’ve seen Io’s immense volcanoes erupt, and we’ve seen huge storms rage on Jupiter, but often these large-scale planetary events are too massive for us to put into context and so we file them under “astronomy”. But, when we see an event like an avalanche on Mars, we can relate it with events on Earth, we have a “feel” for what this means. Suddenly an avalanche on Mars holds a special meaning to us; we instantly have a connection with other planets in our Solar System.

And now for the question… what caused the four near-simultaneous avalanches recently observed by the Mars Reconnaissance Orbiter?
Continue reading “Could Mars Quakes, Seasonal Temperature Changes or a Chance Meteorite Impact Cause Mars Avalanches?”

The Mischievous Nature of Primordial Black Holes

A black hole dining on a star… primordial black holes on the other hand less destructive, but can cause some mayhem nonetheless. Image credit: NASA. Source: http://www.dailygalaxy.com/photos/uncategorized/2007/07/05/black_hole_3_3.jpg

Primordial black holes are strange little critters. They’re not the product of a massive star recently gone supernova and they’re not as exotic as a wormhole, tunnelling a gateway into another dimension. They are very, very old remnants of the very beginning of our Universe. Much like the foamy bubbles left over from washing the dishes, a few bubbles stubbornly hang around on the side of the sink for an hour or so after the water has long gone. Primordial black holes (or PBHs for short) are just that, the leftovers from the very energetic (and very bubbly) Big Bang 14 billion years ago…

…but they’re not done causing trouble quite yet…
Continue reading “The Mischievous Nature of Primordial Black Holes”

Snippet: Where Science and Art Meet – The Internet “Universe” Frozen in Time

San Diego Supercomputer Center image of the Internet Universe frozen in time. Image credit: UCSD. Souce:http://www.physorg.com/news122832578.html

This striking image has been created by tracking the round-trip times of data packets sent from a web site in Virginia to thousands of nodes around the World Wide Web. Using a new technique, this visualization method (3D “hyperbolic geometry”) allows the viewer to analyse large amounts of data mapped around a sphere. Not only does it give an insight to where data travels around the Internet – like an electronic dye highlighting the route packets of data take – it has also become a work of art…
Continue reading “Snippet: Where Science and Art Meet – The Internet “Universe” Frozen in Time”

Snippet: Will the Earth be Safe From Solar Expansion? The Outlook Isn’t Great…

As the Sun runs out of fuel, it will swell… but will it swell enough to swallow the Earth? Image credit: Mark Garlick/HELAS. Source: http://www.sciam.com/article.cfm?id=exoplanet-red-giant-space-astronomy-stars

In 7 billion years time, the Sun will run out of fuel. As it dies, it will swell so big that many predict that it will reach as far as Earth’s orbit. Naturally, the likelihood of the Earth still harbouring life may be debatable (after all 7 billion years is a long, long time), but should the human race still be around, and evolved into something totally unrecognizable, what will we see?
Continue reading “Snippet: Will the Earth be Safe From Solar Expansion? The Outlook Isn’t Great…”

When Stars Collide: LIGO and Gravitational Wave Astronomy

Binary black holes generating gravitational waves. Image credit: Image Credit: K. Thorne (Caltech), T. Carnahan (NASA GSFC). Source: http://lisa.jpl.nasa.gov/gallery/binary-wave.html

The Laser Interferometer Gravitational-Wave Observatory (LIGO) is an ambitious project. The experiment is designed to detect and characterize gravitational waves generated by energetic and massive events in the cosmos. What’s more, as LIGO has two stations situated 3000 kilometres (1870 miles) apart, through triangulation, the location of a star collision or black hole event can be deduced in the sky. Completed two years ago, LIGO has been taking data ever since and the time has now come to begin analysing the results, seeing if the theoretical gravitational wave can actually be observed, bringing us into a new era of astronomy, gravitational wave astronomy
Continue reading “When Stars Collide: LIGO and Gravitational Wave Astronomy”

The Chaotic Nature of Magnetic Reconnection and Coronal Dynamics

TRACE image of a hot coronal loop. Image credit: NASA

The solar corona is a strange place. For the last few decades solar physicists have been trying to understand why it is so hot. Yes, it’s the Sun, and yes, it’s hot, but the corona is too hot. There are many possible solutions to the “coronal heating phenomenon”, but physicists are generally in agreement that this extreme heating is down to waves propagating along magnetic fields, interacting with coronal plasma, or by reconnection events (small explosions). In a study published earlier this year, scientists suggest that to account for the temperatures and densities observed in the corona, chaotic forces may be at work, regulating the scales of reconnection in the coronal plasma.

Continue reading “The Chaotic Nature of Magnetic Reconnection and Coronal Dynamics”

Large Hadron Collider May Help Us Glimpse Into another Dimension

Superstring theory could have some observational basis with the LHC. Image credit: New Scientist

High energy collisions by the nearly-completed Large Hadron Collider (LHC) may be able to generate particles that are sensitive to dimensions beyond our four dimensional space-time. These exotic particles, called Kaluza-Klein gravitons, would be highly sensitive to the geometry of extra-dimensions, giving scientists an idea about what lies beyond our universe. If these particles are detected, and if their characteristics can be measured, then perhaps the extra dimensions predicted by string theory may be proven to exist… [more]

Will Time be Replaced by Another Space Dimension?

Space-time cones - what if time were to disappear?

What if time disappeared? Yes, it sounds like a silly question – and if the cosmos sticks to the current laws of physics – it’s a question we need never ask beyond this article. Writing this article would in itself be a waste of my time if the cosmos was that simple. But I’m hedging my bets and continuing to type, as I believe we have only just scratched the surface of the universal laws of physics; the universe is anything but simple. There may in fact be something to this crazy notion that the nature of the universe could be turned on its head should the fundamental quantity of time be transformed into another dimension of space. An idea like this falls out of the domain of classical thought, and into the realms of “braneworlds”, a view that encapsulates the 4-dimensional universe we know and love with superstrings threaded straight through… [more]

Forget Black Holes, How Do You Find A Wormhole?

A wormhole connecting two points in space-time. Source: http://en.wikipedia.org/wiki/Image:Worm3.jpg

Finding a black hole is an easy task… compared with searching for a wormhole. Suspected black holes have a massive gravitational effect on planets, stars and even galaxies, generating radiation, producing jets and accretion disks. Black holes will even bend light through gravitational lensing. Now, try finding a wormhole… Any ideas? Well, a Russian researcher thinks he has found an answer, but a highly sensitive radio telescope plus a truckload of patience (I’d imagine) is needed to find a special wormhole signature… [more]