Galaxy has Billions of Earths

From the bbc.co.uk article:

There could be one hundred billion Earth-like planets in our galaxy, a US conference has heard.

Dr Alan Boss of the Carnegie Institution of Science said many of these worlds could be inhabited by simple lifeforms.

He was speaking at the annual meeting of the American Association for the Advancement of Science in Chicago.

So far, telescopes have been able to detect just over 300 planets outside our Solar System.

Very few of these would be capable of supporting life, however. Most are gas giants like our Jupiter, and many orbit so close to their parent stars that any microbes would have to survive roasting temperatures.

But, based on the limited numbers of planets found so far, Dr Boss has estimated that each Sun-like star has on average one “Earth-like” planet.

This simple calculation means there would be huge numbers capable of supporting life.

Read the article here.

Update:
It is interesting how this article above compares to this other article I mentioned April 21, 2008. You’ve got to love science.

Top 5 Bets for Extraterrestrial Life in the Solar System

Enceladus

From wired.com

If we ever do find extraterrestrial life in the solar system, it’s probably much more likely to look like a few cells than a walking-and-talking green man. Nonetheless, finding any kind of life beyond Earth would be extraordinary. Here are our best hopes:

Read the article here.

Cosmology: Top 10 articles from 2008

From the newscientist.com article:

Understanding the origin and nature of the universe has been a goal of humans since they first lifted their eyes to the night sky. In the past decade, results that should help us to answers these questions have been pouring in, as cosmology has turned from a theoretical field to an experimental science.

Since its redesign last month, New Scientist has been making the last 12 months’ articles free for everyone to read. Here, in case you missed them, are our top 10 in-depth articles on cosmology

Why Einstein was wrong about relativity

The void: Imprint of another universe?

The hunt for the Un-universe

2008: Does time travel start here?

Is dark matter mystery about to be solved?

Dark energy may just be a cosmic illusion

Black holes may lurk in unexpected places

Inflation deflated: the big bang’s toughest test

Lithium: The hole in the big bang theory

Awaiting a messenger from the multiverse
 

Read the articles here.

Stonehenge builders had geometry skills to rival Pythagoras

From the independent.co.uk article:
Stone Age Britons had a sophisticated knowledge of geometry to rival Pythagoras – 2,000 years before the Greek “father of numbers” was born, according to a new study of Stonehenge.

Five years of detailed research, carried out by the Oxford University landscape archaeologist Anthony Johnson, claims that Stonehenge was designed and built using advanced geometry.

The discovery has immense implications for understanding the monument – and the people who built it. It also suggests it is more rooted in the study of geometry than early astronomy – as is often speculated.

Mr Johnson believes the geometrical knowledge eventually used to plan, pre-fabricate and erect Stonehenge was learnt empirically hundreds of years earlier through the construction of much simpler monuments.

He also argues that this knowledge was regarded as a form of arcane wisdom or magic that conferred a privileged status on the elite who possessed it, as it also featured on gold artefacts found in prehistoric graves.

Read the article here.

Historic pictures sent from Mars

From the bbc.co.uk article:
A Nasa spacecraft has sent back the first historic pictures of an unexplored region of Mars.

The Mars Phoenix lander touched down in the far north of the Red Planet, after a 680 million-km (423 million-mile) journey from Earth.

The probe is equipped with a robotic arm to dig for water-ice thought to be buried beneath the surface.

It will begin examining the site for evidence of the building blocks of life in the next few days.

Read the article here.

Video simulates a spectacular supernova

From the cosmosmagazine.com article:
Simulating spectacular supernovae could help unlock some of the darkest secrets of the cosmos, say scientists. They are using the world’s fastest supercomputer – the Argonne Blue Gene/P – to model exploding stars.

During these video simulations a seemingly innocuous yellow dot appears in the centre of the star. The dot stretches and mushrooms into a gigantic ball of nuclear energy, pushing through to the surface of the star, blistering out and eventually enveloping the star in an immense nuclear deflagration. Watch a video of one of the simulations here.

In reality the process would take less than five seconds and yield an unimaginable quantity of energy. The energy released during the detonation alone is equivalent to 1,027 hydrogen bombs.
…
The whole process of simulating a supernova takes three days using the Argonne Blue Gene/P (BGP) supercomputer, but would take around 1,000 years using an ordinary desktop computer.

Read the rest of the article and see the video here.

Catch Mercury at Its Best

From the skyandtelescope.com article:
Most people have never knowingly seen Mercury. That’s a pity, because viewing the innermost planet is very rewarding, whether you use a telescope, binoculars, or just your unaided eyes.

The problem with Mercury is that it never strays far in the sky from the Sun, so it’s usually visible only very close to the horizon in bright twilight. But people at mid-northern latitudes (the US and most of Canada, Europe, and Asia) have an extraordinarily good opportunity to view the elusive planet on evenings in May 2008. Throughout most of the month, Mercury is high above the western horizon a half hour after sunset, and it’s still reasonably high even an hour after sunset, when the Sun’s glow is quite subdued.

As always when it’s visible in the evening, Mercury is brightest at the beginning of the apparition, fading from magnitude -0.8 on May 1st to 0.3 on May 12th. That’s nearly a threefold decrease, but magnitude 0.3 is still dazzlingly bright.

Read the reast of the article here.

ET Likely Doesn’t Exist, Finds Math Model

From the discovery.com article:
Earth-like planets have relatively short windows of opportunity for life to evolve, making it highly doubtful intelligent beings exist elsewhere in the universe, according to newly published research based on a mathematical probability model.

Given the amount of time it has taken for human beings to evolve on Earth and the fact that the planet will no longer be habitable in a billion years or so when the sun brightens, Andrew Watson, with the United Kingdom’s University of East Anglia in Norwich, says we are probably alone.

Earthlings overcame horrendous odds — Watson pegs it at less than 0.01 percent over 4 billion years — to achieve life. The harsh reality is that we don’t have much time left.

Read the rest of the article here.

Found! Oldest galaxy pile-up

From abc.net.au:
Astronomers have discovered the most distant galactic collisions yet, a cluster of early galaxies caught merging into one giant galaxy when the universe was just a toddler.

The galactic ‘proto-cluster’, named LBG-2377, is a whopping 11.4 billion light-years away and in the past.

It provides a window into a time well after the universe inflated and spread matter far and wide.

But it was still a time when all of that matter was coalescing to make the clusters and super-clusters of galaxies that collectively create the cobwebby structure of matter in the modern universe.

The team used the volcano-top Keck Telescope in Hawaii to capture the image of the galaxies in the act of coming together at about two billion years after the Big Bang.

The discovery was originally part of a broader survey of distant galaxies.

“This particular system showed up as a particularly bright one,” says Dr Jeff Cooke, a postdoctoral researcher at the University of California at Irvine (UCI).

Cooke and his colleagues publish their discovery in the online astrophysics bulletin astro-ph, accessible via the arXiv website.

To be so bright at such a distance, LBG-2377 must be about 10 times the mass of the Milky Way, say the researchers.

They gleaned the number of galaxies involved in the merger from LBG-2377′s spectra of light, which contain multiple galactic signals.

Equally important is the fact that the galaxies have been caught in the act of firing up loads of young stars that are very bright in ultraviolet light.

“It wasn’t at all what I expected,” Cooke says. “The event is so violent and catastrophic and they are creating so many new stars” that it shines far brighter than any other galaxies or clusters of galaxies at such a distance.

“It’s definitely the furthest merging galaxy cluster.”

Read the rest of the article here.

Clashing magnetic fields blast solar winds

From the abc.net.au article:
The solar wind paints earth’s skies with auroras and pushes solar sails through space. But just how the streams of electrically charged particles flow out of the sun has been a mystery until now.

Like most phenomena associated with stars, the process is violent, international scientists have discovered.

Pockets of hot gases on the sun’s surface, which pool around bright knots of magnetic activity, spurt out into space when the sun’s snarling, snaking magnetic fields collide.

“[The phenomenon] has been debated for many years,” says Professor Louise Harra, a University College London researcher who this week unveiled the sun’s secret at a Royal Astronomical Society meeting in Belfast.

Harra planned to show images from the orbiting Hinode spacecraft showing magnetic fields linking two bright spots on the sun.

The spots are nearly 500 million kilometres apart, a distance equivalent to 40 earths placed side by side.

When the magnetic fields smashed into each other, charged gases flew out in all directions, forming the solar wind.

“It is fantastic to finally be able to pinpoint the source,” Harra says, adding that the next step is to figure out how the wind is transported through the solar system.

The solar wind permeates the solar system, defining its shape and scope, as it blasts along at 200 kilometres per second on the slow days.

During snappier binges, strong gusts blasting into earth’s magnetic bubble can have a myriad ramifications from the beautiful and benign aurora above earth’s poles to the shutdown of power and communications systems on the planet.

Read the rest of the article here.