Very well made, and frightening to contemplate:

I note that the star keeps glowing at about the same level of luminosity throughout. At some point, the mass of the star would be less than the threshold required for fusion -- but I'm not sure at what point the fusion process would begin to shut down. Maybe the black hole would swallow the entire star before it had the chance to burn out.

Also, I wonder what the time scale is. Decades? Centuries?

UPDATE: The first time I watched this, I didn't have audio. The narrators says the process takes "millions of years."

(via Geekpress.)

Posted by Phil Bowermaster at 06:25 AM | Permalink | Comments (0)

It's a little bit of time travel and a whole lot of cool astronomy:

Ancient Supernova Explosion Glimpsed Anew

A supernova explosion first seen from Earth 436 years ago has come back to life for astronomers in a time-travel-like astronomical twist.

By observing light from supernova SN 1572 that was slowed on its trip to Earth by dust particles, scientists can watch the outburst now as it would have looked originally.

When the explosion first appeared in the sky in 1572, Danish astronomer Tycho Brahe named it “Stella Nova” or “New Star” because it looked like an extremely bright star that hadn’t been there before. Astronomers today call it Tycho's supernova.

So today astronomers get an up-close look at the cosmic phenomenon that Tycho Brahe observed hundreds of years ago. We're only getting a glimmer, a reflection of the original. And yet I think we're now seeing more than Tycho did...

Amazing.

A well-placed and highly reflective dust cloud bounced the image of the supernova back towards earth, giving us this latter-day shot at seeing the event. This video shows how that worked:

Of course, every time we look into the night sky, we are looking looking at either the recent past (e.g., the moon) or the very distant past (e.g., the Andromeda galaxy.) But it's one thing to see these objects just sitting there, as it were, and quite another to see something happen.

This makes me wonder...are there other past events that we might get a second shot at observing? If a well-placed dust cloud can bring back an event from nearly half a millennium ago, what other options might exist for retrieving visual information on events long since past? I think we'd all have to agree that a dust cloud is a fairly low-tech approach to viewing the past, although clearly it was aided by a high-tech telescope and imaging technology. Still, it makes you wonder.

We discussed on a recent FastForward Radio whether the technology for traveling back in time is possible, and if so whether it is reasonable to expect that it will ever exist. Perhaps going back in time is not in the cards. But seeing the past is a real possibility, as the above image demonstrates.

Posted by Phil Bowermaster at 06:08 AM | Permalink | Comments (1)

When I was a kid, we didn't know for sure whether there were any planets outside the solar system. It seemed likely that there would be planets out there, and one could assert that it was highly probable that they were out there, but we didn't for sure.

Then, suddenly, we did know. Astronomers began to crack the code, identifying the presence of planets by the way stars wobbled and other giveaway behaviors. So then there were a few known planets outside the solar system, and before long there were a few dozen -- to the point where now most people probably couldn't tell you (within 50, or even 100) how many extrasolar planets we have discovered.

Do you know? Take a look.

Surprised?

See we have discovered hundreds them, using various clever indirect detection methods. But no one has ever actually seen an extrasolar planet. Until now, that is:

And then, one the same day we see one, we see two at the same time.

All the details are here. What an amazing time we live in.

Posted by Phil Bowermaster at 11:34 PM | Permalink | Comments (1)

It's happening faster than anyone would have guessed -- with average temperatures rising 15-20 degrees Fahrenheit. One of the results of the spike in temperature is unprecedented violent storm activity, unlike anything that has ever been witnessed in several centuries of observation.

And it's all happening on Jupiter. The Hubble provides this gorgeous image, showing what are now the three red spots of Jupiter -- each one a massive storm system.

The original Great Red Spot is bigger than Earth, and may have been observed as early as the 17th or 18th century. The other two are recent arrivals. It's interesting that, on Jupiter, intensified storm activity is correlated with an increase in average temperature. Here on earth, some experts have recently come to a rather different conclusion.

It's also interesting that such climate change is even taking place on Jupiter and, as we have observed, elsewhere in the solar system. How can this be happening on planets where there are no SUVs, and where George W. Bush was never president?

It just doesn't add up.

Posted by Phil Bowermaster at 11:00 PM | Permalink | Comments (2)

Via satellite.

Posted by Phil Bowermaster at 07:53 PM | Permalink | Comments (0)

Here's a big discovery that was made using some very simple tools:

The Milky Way is twice the size we thought it was

We were tossing around ideas about the size of the Galaxy, and thought we had better check the standard numbers that everyone uses," Professor Gaensler said. Image credit: NASA, ESA, and The Hubble Heritage Team (STScI/AURA)

It took just a couple of hours using data available on the internet for University of Sydney scientists to discover that the Milky Way is twice as wide as previously thought.

Astrophysicist Professor Bryan Gaensler led a team that has found that our galaxy - a flattened spiral about 100,000 light years across - is 12,000 light years thick, not the 6,000 light years that had been previously thought.

Proving not all science requires big, expensive apparatus, Professor Gaensler and colleagues, Dr Greg Madsen, Dr Shami Chatterjee and PhD student Ann Mao, downloaded data from the internet and analysed it in a spreadsheet.

The team came to this new conclusion by measuring how much the output of pulsars slows as it is traveling through the galaxy's warm ionized medium -- the sea of electrons which lies between the stars and various other galactic objects. The team came to its more accurate picture of the galaxy's width by rejecting a number of data points, concluding that the pulsars that le above or below the galactic plane provide more precise measurements than those in the middle.

How interesting that there are such significant discoveries to be made just by looking at existing data in a spreadsheet. I wonder what startling facts are lying in piles of collected numbers and waiting to be discovered?

Posted by Phil Bowermaster at 07:37 AM | Permalink | Comments (2)

Last week we had the exciting discovery of a a solar system very similar to our own:

Two planets much like Saturn and Jupiter are orbiting a star roughly half the size of our sun in a solar system some 5,000 light years away, astronomers say.

The newly discovered complex seems like a parallel star system to the one that includes Earth, researchers say. Both planets are composed largely of gas and each is a bit smaller than its counterpart in our solar system. The smaller planet is about twice the distance from its star as the larger one, just as Saturn is roughly twice as far from the sun as Jupiter.

That's cool, but what we want to find is not so much a solar system like ours as a planet like ours. For that, it turns out that we might have to look as far as we once thought:

A Second Earth in Our Solar System

Traveling to another Earth-like world just got a lot easier. It turns out that there may be many other dirt-and-water planets lurking at the edges of our solar system in places like the Oort Cloud. These planets, which could be roughly the size of our own, would contain all the elements we need for life. They're just sitting in a cold, dimly-lit part of the solar system, waiting to be defrosted and colonized. Yesterday, NASA scientists announced that this changes the prognosis for nearby livable planets.

NASA's Alan Stern said these planets are so far away from the sun that we haven't seen them yet:

Stern says:

Our old view, that the Solar System had nine planets will be supplanted by a view that there are hundreds if not thousands of planets in our Solar System. It could be that there are objects of Earth-mass in the Oort cloud (a band of debris surrounding our planetary system) but they would be frozen at these distances. They would look like a frozen Earth.

Still, it might be something of a stretch to describe these planets as "livable." They're going to be darn cold. However, we ought to be able to think of ways to warm and brighten them up -- maybe by moving them closer to the sun?

Posted by Phil Bowermaster at 06:58 AM | Permalink | Comments (1)

Now this is just peculiar:

Galaxy's spiral arms point in opposite directions

Astronomers are puzzling over a spiral galaxy whose spiral arms are wrapped in opposing directions. The unusual structure may be a lingering scar from a tussle with a smaller galaxy that was ultimately swallowed.

Before astronomers had studied this unusual spiral galaxy, called NGC 4622, they thought the spiral arms of galaxies were always oriented the same way relative to the galaxy's direction of rotation. Specifically, spiral arms were always thought to follow, or trail, the direction of rotation – the same way that a swirl of milk in a stirred cup of coffee naturally orients itself.

But in 2002, astronomers led by Ron Buta of the University of Alabama in Tuscaloosa, US, announced that NGC 4622, which lies 200 million light years away, was rotating the wrong way – its prominent outer arms were leading instead of trailing. And one inner arm even appeared to be wound in the opposite direction from the outer arms.

What could cause such a thing to occur? The prevailing theory is a galactic cataclysm:

Scientists still do not understand how the galaxy got its oppositely oriented arms. One possibility is that the inner arms are the result of a struggle with a smaller galaxy that veered perilously close to NGC 4622 and was swallowed.

Before being ripped to shreds, the smaller galaxy could have stirred up matter in NGC 4622's inner regions, leading it to settle in a spiral pattern opposite to that in the outer regions.

That seems likely. But how about an alternative explanation? What we are seeing is a galaxy that has been re-engineered. The highly advanced inhabitants are using these opposing forces of spin to generate energy or to perform some other task.

Discuss.

Posted by Phil Bowermaster at 09:28 AM | Permalink | Comments (1)

Reader Jeane Schneider points out that the PlanetQuest exoplanet tally of extrasolar planets is a little behind. A more up-to-date count can be found at exoplanet.eu, where they are currently showing a grand total of 268.

The site lists planets by what technique was used to identify them, and also provides a list of controversial and retracted planets. Cool!

Posted by Phil Bowermaster at 06:33 AM | Permalink | Comments (0)

And in the little western Kentucky public library that I frequented when I was a boy, you could still find books that only listed eight. From a strictly local perspective, those formerly long-outdated books are once again up-to-date. Our solar system has only eight planets; the ninth got demoted a while back.

But back in those days, the number of planets in our solar system was equal to the number of known planets. That is no longer the case -- not by a long shot. According to NASA's PlanetQuest site, there are now some 264 known planets out there in the 'verse, though none have been declared officially earth-like. There are 227 stars that have been identified as having planets orbiting them. One of these, 55 Cancri, has five confirmed planets.

We've certainly come a long way. Uranus was discovered in 1781. Neptune was first spotted in 1846. Then Pluto came along in 1930, and was eventually de-planeted primarily because we were finding too many other objects that we would also have to count as planets if we continued to count Pluto. (Eris, for example, which is more massive than Pluto.)

So we had thousands of years of knowing only about the planets that can be seen with the naked eye, then along comes the telescope and we're finding a new one every 70-90 years. Pretty good progress, but it's nothing compared to what happened once astronomers started looking for evidence of extrasolar planets in the tell-tale wobble that a star displays when a planet orbiting the star tugs on it with its own mass.

The NASA site lists PSR 1257 as the first extrasolar planet to be discovered, in 1991. So while thousands of years of naked-eye observation followed by hundreds of years of peering through telescopes never even got us to double digits, a little over a decade and a half has us more than a quarter of the way to quadruple digits. And it's no understatement to say that we're barely scratching the surface. Look at what a limited space (relative to the rest of the galalxy) in which we are currently looking.

And don't forget, there may well be additional planets orbiting the stars around which we've already confirmed the presence of planets. The great age of planetary discovery is not yet even in its infancy, but perhaps we'll be there soon. We may well look back on the time when there were "only" 264 as not terribly different from the time when there were only nine.

Posted by Phil Bowermaster at 06:54 AM | Permalink | Comments (0)

Let's have no more of this nonsensical talk about banning astronomy:

Evidence for a parallel universe?

Last August, astronomers working on the analysis of data being acquired by NASA’s WMAP (Wilkinson Microwave Anisotropy Probe) satellite announced that they found a huge void in the universe. A void is a region of space that has much less material (stars, nebulae, dust and other material) than the average. Since our universe is relatively heterogeneous, empty spaces are not rare, but in this case the enormous magnitude of the hole is way outside the expected range. The hole found in the constellation of Eridanus is about a billion light years across, which is roughly 10,000 times as large as our galaxy or 400 times the distance to Andromeda, the closest “large” galaxy.

The dimension of the hole is so big that at first glance, it results impossible to explain under the current cosmological theories, although scientists put forward some explanations based on certain theoretical models that might predict the existence of “giant knots” in space known as topological defects.

However, University of North Carolina at Chapel Hill physics Professor Laura Mersini-Houghton made a staggering claim. She says, “Standard cosmology cannot explain such a giant cosmic hole” and goes further with the ground-breaking hypothesis that the huge void is “… the unmistakable imprint of another universe beyond the edge of our own“.

I'm not astrophysicist, so I will take it as a given that there can be something remarkable about a large piece of open space out in...space. I mean, isn't that what we expect to find out there? But okay, granted.

Mersini-Houghton is a proponent of a theory of entangled universes. Her ideas about parallel universes are testable, so we should know in time whether this hole is just a big hole or evidence of something more. According to the theory, there should be a second void like this one in another section of the universe.

If such a void is, in fact, found, it still won't be proof positive that we have discovered a parallel universe, but it will certainly add credibility to the argument.

To me, there's something very odd about the idea of evidence of parallel universes in this universe. If we have some common context with another universe, isn't that context the real universe? How can two parallel things be connected to each other? Similarly, Max Tegmark talks about the great physical distance one would have to travel to get from this universe to another universe. (I can't find the exact reference; somebody help me out if you know what I'm looking for.)

Maybe I'm just playing word games, but it seems to me that if you can get there from here, then it's not a different universe.

Posted by Phil Bowermaster at 07:41 AM | Permalink | Comments (3)

Before it, you know, wipes out the universe?

Could humanity's observation of dark energy have shortened the life span of the universe? The answer is "yes" according to the author of a new scientific paper that has recently come to light. Featured in the latest edition of New Scientist magazine, the subscriber-only story, "Has observing the universe hastened its end?", discusses the paper and its claims.

It's the old principle that you can't observe a phenomenon without affecting it. But can it really be dangerous, existentially dangerous, for us to observe some the building blocks of the universe in action?

Maybe.

Once again, this is territory ably covered by Greg Egan in his novel Quarantine, wherein aliens essentially wall off the solar system so that we can't make any more universe-limiting observations of quantum phenomena.

Anyhow, if we really are at risk, this might be a job for the Lifeboat Foundation.

Also, I wonder if MDarling will consider this proof that there really is a God? And an angry, vengeful one at that...

Posted by Phil Bowermaster at 08:06 AM | Permalink | Comments (5)

This is a very well-made video on the subject of whether we're alone in the universe.

I wonder how others are struck by the argument that we should be looking for microbes, not civilizations? The filmmaker argues that civilizations last for only a blip in time, while microbes are around for billions of years. I think civilization as a phenomenon might be a bit longer-lived than he credits it. In fact, we don't really know how long we can expect a civilization, much less a technological civilization, to last seeing as we are still in the very early days of both.

Hat-tip: Boulder Futurists.

Posted by Phil Bowermaster at 07:58 AM | Permalink | Comments (2)

Well, now here's an interesting development:

Sun's 'twin' an ideal hunting ground for alien life

Astronomers have found the most Sun-like star yet, and they say it is an ideal place to hunt for alien civilisations.

The star, called HIP 56948, lies a little more than 200 light years from Earth. Its size, mass, temperature, and chemical makeup are all so similar to the Sun's that no measurable differences could be found in high-resolution observations made by the 2.7-metre telescope at the McDonald Observatory in Texas, US.

Apparently, this star is one of about 17,000 that SETI is currently targeting as similar enough to our own sun to warrant interest. This one is the closest match found to date. It's more than 200 light years away, so any civilization living on one of its planets has not yet been treated to I Love Lucy reruns.

One important difference -- this star is about a billion years older than the sun. So any earth-like planet there would have had more time to develop life and civilization than we did -- assuming that we managed to pull it off fairly quickly. It's so hard to estimate with only one data point. On the other hand, assuming we developed slowly or at about average speed, any civilization that was once there could now be long gone.

Maybe the Lifeboat Foundation should join in on the exploration of these 17,000 stars, looking for clues as to what might have brought past civilizations down. Call it SEETI - the Search for Extinct Extraterrestrial Civilizations.

Posted by Phil Bowermaster at 07:41 AM | Permalink | Comments (4)

Often they have a nice spiral shape. Sometimes they kind of look like the letter S. And then there's this:

You waited for the rectangular galaxy, and now you've got it.

Posted by Phil Bowermaster at 07:52 AM | Permalink | Comments (2)

You are here.

Any questions?

Yes, it is an artist's conception. We haven't sent anyone out to snap a picture from this vantage point quite yet.

Posted by Phil Bowermaster at 07:53 AM | Permalink | Comments (1)

Here's an interesting piece of commentary in The Independent arguing that wantonly announcing our presence to (possible) alien civilizations may not be such a smart move:

This is not just a matter for astronomical research involving distant worlds and academic questions. Could it be that, from across the gulf of space, as HG Wells put it, there may emerge an alien threat? That only happens in lurid science fiction films, doesn't it? Well, the threat is real enough to worry many scientists, who make a simple but increasingly urgent point: if we don't know what's out there, why on Earth are we deliberately beaming messages into space, to try and contact these civilisations about whom we know precisely nothing?

It's interesting to note some of the names of those who are raising these questions:

Physicist Freeman Dyson, of the Institute for Advanced Study in Princeton, has been for decades one of the deepest thinkers on such issues. He insists that we should not assume anything about aliens. "It is unscientific to impute to remote intelligences wisdom and serenity, just as it is to impute to them irrational and murderous impulses," he says. " We must be prepared for either possibility."

[S]cientist and science-fiction author David Brin thinks those in charge of drafting policy about transmissions from Earth - ostensibly a body called the International Astronomical Union, which would make recommendations to the United Nations - are being complacent, if not irresponsible. Whatever has happened in the past, he doesn't want any new deliberate transmissions adding to the risk. "In a fait accompli of staggering potential consequence," he says, "we will soon see a dramatic change of state. One in which Earth civilisation may suddenly become many orders of magnitude brighter across the Milky Way - without any of our vaunted deliberative processes having ever been called into play."

Is this something we should be worried about? I note that "alien invasion" isn't even listed as a serious existential risk for humanity on the Wikipedia list linked by the Lifeboat Foundation, although technically I suppose such a threat would fall under the general heading of War and Genocide. Of course, there are some schools of thought that argue that we needn't worry about alien civilizations because they simply aren't there. Stephen and I took a stab at a couple of those a while back.

Generally, I'm inclined to think that those arguments are on the right track. If there are aliens, there should be at least one so far ahead of us that its presence in the universe would have announced itself to us by now. Or there may be several advanced civilizations, but once a civilization reaches a certain level of advancement, it just "drops out" of the universe -- or at least the universe as we understand it. Either way, not much of a threat.

Still, there could be other options. Maybe technological development slows down after a while. Maybe colonizing the galaxy doesn't appeal to some civilizations, but they don't mind going out and eliminating the occasional upstart threat whenever they find out about them. What about a civilization where some extreme ideology -- political or religious fundamentalism -- accompanied by advanced technology freezes development at a certain threatening level?

It's all just guesswork, of course. But then that's the thing about alien civilizations. We really don't know anything about them. It's guesswork, with different guesses informed by different assumptions and biases. Right now, we're discovering new planets right and left and our own technological prowess is growing exponentially. We'll no doubt understand the situation a lot better a few years down the road.

Meanwhile, we keep guessing. As we do, I don't see how adding a little caution to the mix could possibly hurt.

Posted by Phil Bowermaster at 07:13 AM | Permalink | Comments (4)

...in the neighborhood.

And, yes, all those bright spots are galaxies.

UPDATE: Hmmm...I don't want to throw anybody off with the term "bright spots." What I mean to say is -- every single speck you see, no matter how faint, no matter how many might be piled upon one another -- is a galaxy, a huge body containing anywhere from 10 million to one trillion stars.

Okay, then. Just so we're all clear on the scale and/or scope. I figured we all were, but one can't be too careful with these things.

Posted by Phil Bowermaster at 04:50 PM | Permalink | Comments (3)

Shiny!

Posted by Phil Bowermaster at 07:49 AM | Permalink | Comments (0)

French Astronomers have announced the discovery of an Earth-like planet orbiting the red dwarf Gliese 581. This is 20.5 light years away in the Libra constellation. They claim that the surface temperature runs between 32 and 104 degrees F (that's 0 - 40 degrees Celsius).

"Liquid water is critical to life as we know it and because of its temperature and relative proximity, this planet will most probably be a very important target of the future space missions dedicated to the search for extra-terrestrial life. On the treasure map of the Universe, one would be tempted to mark this planet with an X," added Xavier Delfosse, a member of the team from Grenoble University, France.

A red dwarf is much cooler than our Sun, so the habitable zone of a red dwarf is much closer to its star. This planet is 14 times closer to its star than our planet is to the sun.

This is all speculative on my part (I'd appreciate an astronomer weighing in), but I have some question whether stars much smaller than our sun actually have a habitable zone. Being that close to a star - even a star as dim a red dwarf - might be too radioactive for life to develop.

The other potential problem is tidal lock. A celestial body that closely orbits another larger celestial body tends to present the same face to that larger body. The best example is the Moon. We always see one face of the Moon. If the "habitable zone" of a small star put it within tidal lock range, one side of the planet would be boiling and the other side would be frozen. That would not be conducive to life either.

Congradulations to the French team that discovered this planet! May it be the first of many.

UPDATE:

From the comments Karl Hallowell adds:

The problem with red dwarf stars is that they still have significant stellar flares. And that can be quite lethal at the distances that one needs to be to keep warm.

UV radiation isn't a significant problem. The spectrum of a "black body" drops rapidly from the peak (Gliese 581 has a temperature of 3,478 K while the Sun has a temperature of 5785 K). Given that for the planet to be "Earth-like" in temperature, it must be receiving similar amounts of total energy from the star. Hence, it probably receives less UV than we do from the Sun. It also probably receives less visible light (usable for photosynthesis) as well.

So the background radiation environment is probably better, but the stellar flares probably make the environment extremely hazardous to most Earth life...

And Vadept:

According to the story I read on Yahoo, it IS tidally locked. That would suggest that if there is life, it probably exists in the "twilight" regions of the world.

Really, though, the great advent of "C" isn't that they found a world that might contain life, it's that they found an earthlike world in a habitable band of the star. This isn't a Super Jupiter within an AU of the star.

This means, to my mind, not only is the technology to find MORE earth-like worlds there, but that, if they could find one so "easily" (after looking at a mere hundred stars), then there's probably quite a few of these out there. If there's quite a few of them, it's quite likely we will find a planet with undoubtadly the right mix for life...

Thanks for the great comments.

Posted by Stephen Gordon at 02:52 PM | Permalink | Comments (8)

Recent discoveries suggest that Brown Dwarfs, the get-no-respect Rodney Dangerfields of stellar types, act kind of like those mysterious pulsars with their super-powerful blasts of radiation, only on a smaller, brown-dwarf-appropriate scale:

How pulsars produce their radiation has been a problem in astrophysics for 40 years.

This is because we have little understanding of how hot, electrified gas, or plasma, behaves in the extreme conditions present at a pulsar.

Brown dwarfs are now the second class of stellar object known to produce persistent levels of extremely bright, "coherent" radiation.

Greg Hallinan from the National University of Ireland in Galway and his colleagues used the Very Large Array radio telescope in New Mexico to observe a very cool, rapidly rotating brown dwarf called TVLM 513-46546.

Dr Hallinan said: "Our research shows that these objects can be fascinating and dynamic systems, and may be the key to unlocking this long-standing mystery of how pulsars produce radio emissions.

"It looks like brown dwarfs are the missing step between the radio emissions we see generated at Jupiter and those we observe from pulsars".

A while back I called on readers to submit their best ideas as to what use brown dwarfs could be put to. At the time, I believe there were some who saw this exercise as the worst kind of fanciful speculation, but now I feel that I stand vindicated.

After all, the practical uses we might have for brown dwarfs will almost certainly get us started on what do with all those pulsars!

Posted by Phil Bowermaster at 11:04 AM | Permalink | Comments (0)