Forget Black Holes, Let’s Look For Black Rings

A bubble ring. Could a black hole take on this shape at higher dimensions? (©letsdiveguam.com)

Black holes are as extreme as anything can get. When a massive structure can no longer sustain its own gravity, it will collapse to a point known as a singularity. For example, a massive star after it has gone supernova may leave one of these singularities behind, a remnant of massive star death, sucking any local matter into a one-way trip to the guts of space-time.

At a certain point, when light itself succumbs to the black hole’s gravity, an event horizon forms, beyond which universal physics breaks down; we have very little idea about what lies inside the event horizon. All we do know is that you don’t want to fall into one, you’d be stretched and spaghettified. Spaghettification is due to extreme (and when I say extreme, I mean as-extreme-as-it-can-get) tidal forces between your head to your toes.

So, the message is: Don’t play with black holes, it can only end in tears.

Now the Black Hole Health & Safety lecture is over, it’s time to talk about “black rings”. Under certain conditions, black holes may not be the mathematical singularities we once knew and (thought we) understood.

In a recent publication by Masashi Kimura at Osaka City University in Japan, the black ring idea is explored in 5-dimensional space. In the space-time we know and love, there are three spatial dimensions and one temporal dimension. We are four-dimensional creatures. When string theory came along in the 1980’s we really began to appreciate that there could be more than the four dimensions we live in.

Previously, cosmologists have entertained the thought that black rings may exist in our 4D space-time. However, the big problem comes when trying to understand how these structures maintain their shapes; surely they should simply collapse and form your regular black holes? Actually, it depends on how big they are and how the competing forces balance out.

As the Universe is expanding, it is thought black rings could exist if they are of scales similar to the cosmological constant (this constant was derived by Einstein to explain a “flat” Universe, but later it was found the constant was required to characterize the universal expansion as observed by Edwin Hubble in 1929). If a black ring exists in 4D space-time, its gravitational collapse would be countered by the expansion of space-time (as characterized by the cosmological constant).

A bubble ring, as made by a dolphin, for fun (©deepocean.net)

A bubble ring, as made by a dolphin, for fun (©deepocean.net)

The only analogy I can relate this to in the terrestrial world is bubble rings (or, indeed, smoke rings). When under water, a bubble will rise to the surface. However, under the constriction of surface tension, the bubble will form the smallest possible shape. When a bubble ring is produced, there needs to be a balance between surface tension and a vortex. The surface tension pulls in, while the vortex maintains the bubble ring shape, pushing out.

In the case of the black ring, gravity is pulling inward, while the expansion of space-time is countering it, pushing out. In this situation, in an expanding Universe, there could be enduring examples of black rings out there.

In Kimura’s research, not only are black rings a possibility, there could be a number of different complex shapes that could form when considering these extra dimensions. When the Universe was young, multiple interacting black rings may have been possible, eventually coalescing to form black holes.

Although this research is very interesting, it is hard to imagine how we could observe these higher-dimensional black rings. Would we see them as a singularity (i.e. a black hole) in our 4D space-time? Or would they even be unobservable for lower-dimensional beings such as ourselves?

Publication: Dynamical Black Rings with a Positive Cosmological Constant, Masashi Kimura, 2009. arXiv:0904.4311v2 [gr-qc]

Via: arXiv blog

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Is Pluto Affected by the Pioneer Anomaly?

pluto

The Pioneer Effect is a mysterious observation of a number of man-made probes that venture through and beyond the Solar System. Originally noticed in the slight drift of the Pioneer 10 and Pioneer 11 spacecraft (launched in 1972 and 1973) from their calculated trajectories, scientists have been at a loss to explain the tiny, yet constant, extra-sunward acceleration.

Some theories suggest that invisible clouds of dark matter are slowing these probes down, causing them to be influenced by the Sun’s gravity more than expected. Other suggestions include ideas that Einstein’s theory of General Relativity needs to be tweaked when considering interplanetary distances.

However, there are other, more mundane ideas. Perhaps there is a tiny fuel leak in the probes’ mechanics, or the distribution of heat through the spacecraft is causing a preferential release of infrared photons from one side, nudging them off course.

Finding an answer to the Pioneer effect probably won’t surface any time soon, but it is an enduring mystery that could have a comparatively simple explanation, within the realms of known science, but there’s also the possibility that we could also be looking at some entirely new physics.

In an attempt to single out whether the Pioneer anomaly is an artefact with the spaceships themselves, or unknown in the physics of the Universe, astronomers decided to analyse the orbits of the planets in the outer Solar System. The rationale being that if this is a large-scale influence, some observable periodic effects should be evident in the orbit of Pluto.

So far, no effect, periodic or otherwise, has been observed in the orbit of Pluto. If the effect isn’t big enough to influence Pluto, does this mean we can narrow the search down to spaceship-specific artefacts?

Not so fast.

Gary Page and John Wallin from George Mason University in Virginia and David Dixon from Jornada Observatory in New Mexico, have published a paper pointing out that the suggestion that the Pioneer effect doesn’t influence Pluto is flawed. Pluto’s orbit is far less understood than the orbits of the inner Solar System planets, as, let’s face it, Pluto is far away.

We simply don’t possess the data required to cancel out the Pioneer effect on planetary bodies in the outer-Solar System to reach the conclusion the anomaly doesn’t influence Pluto.

Of course, this does not mean that the Pioneer effect exists. It does mean that we cannot deny the existence of the Pioneer effect on the basis of motions of the Pluto as currently known.” — Page et al., 2009

So, back to the drawing board. This is a fascinating study into a true Solar System mystery; bets are on as to the real reason why our interplanetary probes are being knocked off course…

Source: The Physics arXiv Blog

Could US Space Tourism be Snuffed Out by Red Tape?

bigelow_sundancer_02

Here’s a problem we didn’t see coming. Actually, we might have guessed it could be an issue, but thought, “no way, this is space travel we’re talking about!” But yes, red tape might get in the way of space tourism interests in the USA. In particularly, if you’re not an American citizen.

US export controls could potentially throw a problem or two into the space tourism mix, preventing non-US fee-paying customers from taking a ride on Virgin Galactic’s SpaceShipTwo, or doing microgravity cartwheels inside Bigelow’s Sundancer space hotel.

Although Richard Branson is building the world’s first spaceport in New Mexico and XCOR has signed up its first Danish space tourist, the International Traffic in Arms Regulation (ITAR) rules might prevent non-US citizens from seeing the insides of space vehicles containing technology or equipment under the jurisdiction of ITAR.

It’s a national security “thing”.

It’s funny how rules and regulations get in the way of things, but this is possibly the worst time for the issue to crop up. US companies are already promoting and selling their tickets for sub-orbital joyrides to international consumers, what if a British $200,000 ticket-holder turns up at their spaceplane, only for space border control to tell you to go home? Not so good for business is it? In fact, that’s the kind of thing that prevents you from doing business with international clients. To make it worse, potential European space tourism companies are marketing “ITAR-free” components and technologies, thereby creating untouchable competition.

However, despite the concern, I’m thinking there will be a few work-arounds for the ITAR. Key to the regulations is that ITAR covers tech and passengers. How about cutting out the “passengers” bit?

One of my favourite spaceflight companies, Bigelow Aerospace, has asked the same question and has been forward-thinking enough to lobby the government to change ITAR rules. “We think hardware should be [covered] under ITAR,” said Michael Gold, director of Bigelow Aerospace’s Washington office, “but passengers should be exempted.”

It would appear Congress needs some convincing that this particular ribbon of red tape needs to be cut.

Congress created a bigger problem than already existed,” said Rep. C.A. Ruppersberger (D-Md.), who oversees these regulations on the House Select Committee on Intelligence. Unless ITAR is reformed, space commercialization could shift toward China or Russia. However, a lot of committees are being consulted and paperwork is being re-shuffled to find a solution to this issue before real damage is done to a (potentially) revolutionary burgeoning industry in the US.

A balance between space commerce and national security needs to be found, without compromising either to international entities.

Source: Aviation Week

The Space Station Flares, Again!

I don’t usually post two identical stories within a few days of one another, but when I saw this image on SpaceWeather.com I had to comment on it. On Friday, I was captivated by the astounding astrophotography by Nicolas Biver as he tracked the space station with video camera and telescope, to capture some great detail of the manned outpost as it passed over France. With a bit of luck and a whole world of skill, Biver observed a bright space station flare.

Next up, it’s the turn of Martin Gembec. On May 2nd, he grabbed this superb trail as the station passed through the distinctive edge-on disk of our galaxy over the Czech Republic. What’s more, the station flared as its huge solar arrays reflected sunlight through Gembec’s ‘scope… right at the moment when the station travelled through the hazy starlit disk of the Milky Way.

The ISS flares as it passes through the Milky Way's disk (©Martin Gembec)

The ISS flares as it passes through the Milky Way's disk (©Martin Gembec)

We were watching a bright flyby of the space station when the ISS surprised us with a big flare in the Milky Way,” said Gembec. “At maximum, the ISS reached magnitude -8.”

A magnitude of -8 makes this flare a beast; that’s 25× brighter than Venus and 400× brighter than the star Sirius.

In the photo above, there is a rather ominous piece of kit attached to a boom reaching into the centre of the image. This is a reflection of Gembec’s Canon 30D camera (that took the picture as the ISS passed overhead) in an all-sky mirror. The mirror is in a concave shape to collect the starlight from the sky, bouncing the light into the camera lens. It acts much like a satellite dish; except it doesn’t bounce and focus radio waves into an antenna, the all-sky mirror reflects visible light and focuses it into the open camera shutter. As you can see, the results are visually stunning.

Source: Space Weather

2012: Not Doomsday, It’s the Last Stand for an Ancient Civilization

maya_cartoon

My good friend, talented writer and co-author Greg Fish, sent me this cartoon last night and I got a giggle out of it, so I thought I’d share. I think it exemplifies just how something so small can be blown completely out of proportion. Although the cartoon depicts two Mayans constructing the “Sun Stone”, it was actually the Aztecs, another mesoamerican culture, who constructed the Sun Stone. But that’s not the point of this article (besides, several doomsayers are clueless about the difference between Mayans and Aztecs anyway).

The Mayans built a calendar so they could better organize their time, document historical events and enable them to make plans for the future (like any good calendar does). So, out of necessity, the Mayans put together an amazingly complex system of embedded calendars of various lengths. They came up with an innovative idea so they didn’t have to rely on short-term cyclical calendars (the longest was only 52 years), they created one of the first number-based calendars devised:

The Mayans had a solution. Using an innovative method, they were able to expand on the 52 year Calendar Round. Up to this point, the Mayan Calendar may have sounded a little archaic – after all, it was possibly based on religious belief, the menstrual cycle, mathematical calculations using the numbers 13 and 20 as the base units and a heavy mix of astrological myth. The only principal correlation with the modern calendar is the Haab’ that recognised there were 365 days in one solar year (it’s not clear whether the Mayans accounted for leap years). The answer to a longer calendar could be found in the “Long Count”, a calendar lasting 5126 years.” — Me, “No Doomsday in 2012“, Universe Today, May 19th, 2008 (there’s nothing quite like pimping your own megahit articles!)

Palenque Museum Mayan glyphs (wyattsailing.com)

Palenque Museum Mayan glyphs (wyattsailing.com)

So, the Mayans created a number system that lasted 5126 years. Judging by their love of cycling calendars that reset after 260 days (Tzolk’in calendar), 365 days (Haab’) and 52 years (Calendar Round), isn’t it logical to assume the Long Count calendar was designed to do the same thing? And why didn’t the Mayans explicitly say: “the Long Count will cycle again after 5126 years“? That’s because they were still in their first cycle. And within this first cycle, their entire civilization rose and and crashed back down again. They never got the chance to experience one whole cycle, resetting the Long Count or, indeed, simply extending it.

In short, the world isn’t going to end in 2012 (the coincidental end-date of the Mayan Long Count calendar), it’s the last stand of an ancient culture.

It’s actually rather sad; assuming the historians are correct, and the Long Count does end on December 21st, 2012, that is the final end date for an entire civilization. Although their cities may have crumbled and civilization faded into the history books, at least the Mayans had a calendar that endured hundreds of years after their downfall. The Mayan Long Count calendar outlived a civilization, perhaps December 21st, 2012, should be a celebration of a lost mesoamerican race, as this date will truly be the end of ancient Maya.

For more about the myths, lies and deception surrounding 2012, check out my “No Doomsday in 2012″ articles »

Space Station Flare Captured On Film

I’ve been watching this short video clip over and over. It may only be two seconds long, but it is such a unique view of the space station that I find it mesmerizing. Each time the animated GIF loops, another detail seems to reveal itself.

The ISS flare, as observed by Nicolas Biver from Versailles, France, on April 28th (©Nicolas Biver)

The ISS flare, as observed by Nicolas Biver from Versailles, France, on April 28th (©Nicolas Biver)

It’s also kinda hypnotizing in a rhythmic way; the space station appears to turn and boost away into the black of space, but just before its massive solar arrays capture the sunlight, dazzling the observer with a flash.

Is it me, or are those solar panels reminiscent of the sails hoisted up the masts of canon-touting battleships before the age of iron-hulled vessels and steam-powered engines? These slightly fuzzy images could even be from the turn of the 20th Century, when one of the first movie cameras filmed a ship steering out of port.

Of course, this isn’t a wooden ocean-going ship, it’s the space station, in orbit. And the video was taken with a modern digital camera through a 16-inch Dobsonian telescope by a highly skilled amateur astronomer called Nicolas Biver from Versailles, France. The reason why the station appears to “turn” is because the perspective of the observer changes as the station flies overhead, he did a great job of tracking it.

On April 28th, Biver tracked the space station through his ‘scope. Whether it was intentional or not, he was fortunate to capture an intense flare as the space station’s solar panels reflected sunlight at his location. The resulting flare was much brighter than Venus (after the Moon, the station is the second brightest object in the night sky). Usually when I hear about observations of flares made by stuff in orbit, I usually think of Iridium flares that occur at predictable times and locations, providing a target for observers on the ground to capture a meteor-like streak across the sky. The Iridium satellite network provides a great chance for astronomers to see the reflected light when the angle between them, the satellite’s solar panels and Sun is just right.

My astronomer friend Tavi Greiner (who has just joined the Astrocast.TV team as host of Our Night Sky, be sure to check it out!) is very skilled at observing the Iridium flare-ups, and as can be seen in this image, those things are bright.

However, on the 28th, it was the space station’s turn to reflect some light for Nicolas Biver.

In March, Space Shuttle Discovery completed the construction of the ISS solar arrays during the STS-119 mission. Over a series of space walks, the solar array had its area boosted to 16,000 square feet. With this extra surface area, comes the potential for very bright flaring events.

For the chance to view the ISS and possible flaring, check out SpaceWeather.com’s Simple Satellite Tracker.

Source: Space Weather

Laboratory Ice Links Comets with Life On Earth

Artist impression of the nucleus of Comet Tempel (NASA)

It is an established theory that comets may have, in some way, seeded life on Earth. Some extreme ideas support the panspermia concept (where bacterial organisms hitched a ride on comets, asteroids or some other planetary debris, spreading life throughout the Solar System), while others suggest comets may have contributed the chemical building blocks essential for life to form 4 billion years ago. We know these icy bodies are also awash with organic compounds, so it’s not a huge leap of the imagination to think comets may have donated life-making material to the early Earth.

In an effort to study cometary material and its possible influence for nurturing early life on Earth, Prof. Akiva Bar-Nun of the Department of Geophysics and Planetary Sciences at Tel Aviv University has been creating his own comets in the laboratory. By doing this, Bar-Nun is hoping to gain a better perspective on how comets acquired their composition of the noble gases Argon, Krypton and Xenon.

The proportion of these elements are found in the Earth’s atmosphere, but are not thought to have originated from the rocky material our planet consists of. By understanding the proportions of these elements that formed in the icy laboratory environment, if the proportions match that of what we’ve measured on Earth, it goes to some way in explaining how comets formed in space and how they delivered organic compounds to the surface.

Now if we look at these elements in the atmosphere of the Earth and in meteorites, we see that neither is identical to the ratio in the sun’s composition,” said Bar-Nun. “Moreover, the ratios in the atmosphere are vastly different than the ratios in meteorites which make up the bulk of the Earth.”

So we need another source of noble gases which, when added to these meteorites or asteroid influx, could change the ratio. And this came from comets.”

Prof. Bar-Nun and his team carried out the research using a comet-making machine unique to Tel Aviv University, and although the original press release is light on the details, it is assumed the chemical composition of the early Solar System was recreated and then deep-frozen.

Comets bombarded the Earth 4 billion years ago. Organic chemicals were therefore deposited, possibly kick-starting life (NASA)

Comets bombarded the Earth 4 billion years ago. Organic chemicals were therefore deposited, possibly kick-starting life (NASA)

Comets formed some distance from the Sun (and a vast number of them populate the Oort Cloud), water vapour would have condensed and frozen, in temperatures as low as -250°C, trapping a primordial collection of chemicals inside their dusty, icy interiors. Some time after, these comets may have fallen into the inner Solar System, many impacting the Earth. Amino acids may have been introduced to the surface and oceans, or vital chemical components from the comets combined with chemicals already on Earth and life was sparked. When this happened, these comets would have left a chemical fingerprint.

Bar-Nun’s team were successful in creating their own synthetic comet, freezing water vapour, creating a natural ratio between the three elements. Then a link could be made, from the laboratory comet, with the very definite noble gas proportions, and the proportions of these gases found in the atmosphere.

The pattern of trapping of noble gases in the ice gives a certain ratio of Argon to Krypton to Xenon, and this ratio — together with the ratio of gases that come from rocky bodies — gives us the ratio that we observe in the atmosphere of the Earth,” added Bar-Nun.

Judging by the information available (the paper is published in the journal Icarus), Bar-Nun’s research has provided evidence that comets left a unique ratio of stable noble gases in the atmosphere, a ratio of necessary materials for life to eventually form.

Source: Tel Aviv University, EurekAlert via @Avinio

The Russian Rocket-Powered Lander. What Could Possibly Go Wrong?

russian_spaceship_next

Let’s face it, Soyuz is getting old. It’s not that the spaceships themselves are getting rickety, there have been many incarnations, but the original Soyuz design was first conceived in 1966, so the Russian space agency (Roscosmos) is feeling it’s about time for a change. Soyuz has carried out the most manned missions into space out of any other space flight system (over 100 since the 1960s), so Russia has every right to be proud of its achievements.

So what system does Roscosmos want to replace Soyuz with? Perhaps a bigger version of Soyuz? Perhaps a revolutionary winged spaceplane? Nope. They are currently looking at plans for a Soyuz-esque capsule that will re-enter the Earth’s atmosphere much like before. But due to political pressure (spawning the need to move Roscosmos’ operations out of Kazakhstan), engineers must find a way to land the return vehicle in a minuscule area. Measuring only 2×5 km (yes, that’s a tight 10 km2), the landing strip will be as unforgiving as the new method to land the descent vehicle.

There will be no parachutes and no wings; the new concept will use a rocket-powered landing system alone, creating the first ever rocket-powered Earth-lander. If you thought that was a rather extreme design specification, you might be surprised to hear that engineers want to start firing these landing thrusters when the descent module is only 600-800 metres from the ground
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Cassini Detects Salt: Enceladus Probably Has a Liquid Ocean

The small icy Saturn moon might have liquid sub-surface oceans after all (NASA)

In October 2008, Cassini flew very close to the surface of Saturn’s icy moon Enceladus. From a distance of only 50 km from the moon, the spacecraft was able to collect samples of a plume of ice. In an earlier “skeet shot”, Cassini captured detailed images of the cracked surface, revealing the source of geysers blasting the water into space. At the time, scientist were able to detect that it was in fact water ice, but little else would be known until the molecular weight of chemicals in the plume could be measured and analysed.

At the European Geophysical Union meeting in Vienna this week, new results from the October Enceladus flyby were presented. Frank Postberg and colleagues from the Max Planck Institute for Nuclear Physics have discovered traces of sodium salts and sodium bicarbonate in the plume for the first time.

It would appear that these chemicals originated in the rocky core of the moon and were leached from the core via liquid water. The water was then transported to the surface where it was ejected, under pressure, into space. Although scientists are aware that the chemical composition in the plume may have originated from an ancient, now frozen, sub-surface ocean, the freezing process would have isolated the salt far from the surface, preventing it from being released.

It is easier to imagine that the salts are present in a liquid ocean below the surface,” said Julie Castillo of NASA’s Jet Propulsion Laboratory in Pasadena, California. “That’s why this detection, if confirmed, is very important.”

This is the best evidence yet that Enceladus does have a liquid ocean, bound to cause a stir amongst planetary scientists and re-ignite excitement for the search for life living in a salty sub-surface ocean.

Source: New Scientist

Every Reason Not To Worry About Doomsday In 2012

Image credits: Harold Edgerton (1964), NASA. Edit: Ian O'Neill

In today’s 365 Days of Astronomy, Cameron Hummels and Josh Schroeder from Columbia University, New York, discuss the 2012 doomsday hype. And it is awesome. The special thing about this podcast is that Cameron (who is working toward a PhD in astronomy) is clear, concise, and makes the whole crackpot 2012 doomsday scenario sound as petty as it really is.

In 10 minutes, the pair run through ancient prophecy, Mayan calendars, Planet X, galactic alignment and solar flares (to name a few) and carry out possibly one of the most comprehensive debunking efforts I have ever heard. They pretty much summed up all of my “No Doomsday in 2012″ articles with a huge helping of skeptical thinking, plus extras, pointing out that all the doomsday hype is driven by little more than a small group of irresponsible individuals wanting to make some fast money from people’s fear.

Congratulations Cameron Hummels and Josh Schroeder, you’ve just scored one huge point for rational thinking and produced a wonderful celebration of scientific endeavour!

Go to the 365 Days of Astronomy podcast page to listen in »

Show description:

An increasing number of people believe that December 21, 2012 will mark the end of the world. Proponents of this idea cite diverse astronomical reasons for an imminent apocalypse: the end of the Mayan long-count calendar; an alignment between the Solar System and the Milky Way; the solar sunspot cycle reaching an all-time high; the reversal of the Earth’s magnetic field; and a devastating collision with ‘Planet X’. Tune in to hear to the facts and controversy surrounding this purported impending disaster.