Messier 30 is an unusual cluster. It's an ancient cluster, and yet it is filled with blue stars, stars that tend to age and die more quickly than other types of stars. Astronomers have termed these unusually old blue stars "blue stragglers," and they believe that there are two reasons these stars still exist.

Some of the blue stragglers in Messier 30 are vampires; when they get near a more massive star, they are able to siphon off hydrogen from that star, effectively lengthening its life. But more recent studies have found that some of the stars are the results of high-powered collisions. When two older stars collide head-on, it restokes their nuclear fusion, resulting in larger, seemingly younger blue stars than before.

Vampires and collisions rejuvenate stars [Hubble Information Centre via Bad Astronomy]

Gelatinous orbs, etc. A downloadable montage of all four, at the link. [Hubble]

A clash among members of a galactic grouping called Stephan's Quintet.

A panoramic portrait of a colorful assortment of 100,000 stars residing in the crowded core of Omega Centauri

An eerie pillar of star birth in the Carina Nebula rises from a sea of greenish-colored clouds.

The Trifid Nebula not only appears to have three lobes when observed from afar, but closer inspection reveals that it is actually made of three distinct types of nebula clouds. This image comes from the La Silla Observatory in Chile, and it shows off, in the visible spectrum, the beauty of the Trifid Nebula's three part cosmic factory.

The first part is visible here as the blue section at the top of the image. This is referred to as a reflection nebula. It's basically a giant hazy dust cloud that scatters light shed by newly created stars. The brightest stars born in the Trifid Nebula glow blue, so that mixed with the predominantly blue scattering of this dust cloud creates the blue haze at the top of the Trifid Nebula.

The pink area in the middle of the nebula is due to a pretty typical emission nebula. When the predominant gas in this nebula, hydrogen, is heated by the very new stars in this region, it shines red.

The dark bands that originally earned the nebula its name are actually dark nebulae, or strips of light-obscuring dust. This dust is mostly coalesced from previous star births within the nebula. Eventually, within these darker strips, more gas and dust will pull together, creating new stars.

When taken together, these three component nebulae could be seen as the environs of the very beginning of the star cycle, a sort of factory floor for star creation. It could also be seen as the factory showroom, as these newly created stars interacting with space dust creates a pretty stunning spectacle.

Trisected Nebula Seen in Fresh Detail [LiveScience]

Star trails reflect the rotation of the Earth, showing how the stars seem to spin in concentric circles around a fixed point in the sky. Photographers who want to capture these trails take several short-exposure pictures over a period of days, weeks, or even months. The resulting pictures are unique, because the camera is able to capture subtle differences in chemical make-up and color that the human eye is unable to discern. Thus, the individual rings are far brighter and more varied than you might expect from simply looking up at the stars yourself.

Star Trails: Secret Paintings of the Night Sky [Environmental Graffiti]

The new images are built out of only the sharpest, clearest pictures of the star. These sharp images are composited together to create one highly detailed image. The whole process is called "lucky imaging," and it has led to new information about how this star loses so much mass.

The picture shows large plume of gas jetting out from the star's surface. The plume is almost as large as our solar system, and it could help explain where so much of Betelgeuse's mass is going. It also makes for a really beautiful image.

Sharpest views of Betelgeuse reveal how supergiant stars lose mass [via EurekaAlert]

(Image: ESO/L. Calçada)

Betelgeuse is so large and bright (and so relatively close) that it's had its surface photographed and its size measured, and it appears larger than most other stars when viewed by the Hubble Telescope. But it's getting older and, like its red giant counterparts, dying. But unlike other red giants, which scientists have observed swelling before death, Betelgeuse is shrinking.

According to Live Science:

In 1993, measurements put Betelgeuse's radius at about 5.5 astronomical units (AU), where one AU equals the average Earth-sun distance of 93 million miles, or about 150 million km. Since then it has shrunk in size by 15 percent. That means the star's radius has contracted by a distance equal to the orbit of Venus.

"To see this change is very striking," said Charles Townes, a UC Berkeley professor emeritus of physics. "We will be watching it carefully over the next few years to see if it will keep contracting or will go back up in size."

Scientists don't know if this is normal behavior, a potential harbinger of its imminent demise or part of an inevitable decline. For the moment, though, Betelgeuse continues to shine as bright as ever.

Popular Giant Star Shrinks Mysteriously [Live Science]

According to NASA, studying NGC 2841 has helped an international team of astronomers discover that stars flow out of the "hot, dense nurseries" and then disperse to form the smooth distribution pattern that we usually see in similar spiral galaxies. This image is a composite of three different images from the Spitzer Space Telescope. The shorter wavelengths are represented in blue, and the show the oldest stars, plus foreground stars in our own galaxy. Green represents the medium wavelengths, and red is the longest wavelengths. [Spitzer Space Telescope]

A group of scientists from California using the Spitzer Space Telescope have examined the debris rings around six different white dwarfs, one of which is depicted above in this artist's rendering. What they found was that a lot of these shattered rocks were low in carbon but high in other minerals common to rocky planets in our solar system. Planets in our system are also low in carbon.

The researchers announced their findings at this week's meeting of the American Astronomical Society in Long Beach, CA. According to Centauri Dreams:

When a star like our Sun reaches the end of its life and becomes a red giant, it consumes any inner planets and perturbs the orbits of the surviving planets and asteroids. A white dwarf is the end result of this stellar expansion and subsequent collapse. Objects wrenched out of their former orbits should, like the asteroids in question, occasionally drift close enough to the star to be pulled apart by its gravity. Such a star, showing the excess infrared signature of a circumstellar disk that is likely caused by the tidal disruption of asteroids, is called a ‘polluted’ white dwarf.

And that's what we're seeing here.

SOURCE: Astronomical Journal.
Image via NASA/JPL-Caltech.

Professor John Learned suggested that a civilization could attempt to initiate communication with other advanced civilizations by making unnatural alterations to Cepheids, relatively rare stars that other civilizations are likely to study:

Cepheids dim and brighten regularly, in a pattern that depends on their brightness. This lets astronomers measure the distance to the stars, helping to resolve mysteries such as the Universe's age and how fast it is expanding. As such, any sufficiently advanced civilization would want to monitor such stars, the scientists reasoned.

To send messages using a Cepheid, Learned and his colleagues suggest that extraterrestrials might change the star's cycle. A Cepheid becomes dimmer as ionized helium builds up in its atmosphere. Eventually, the atmosphere expands and deionizes, restarting the cycle.

Firing a high-energy neutrino beam into a Cepheid could heat its core and brighten the star early - "just as an electric pulse to the heart can make it skip a beat," Learned says.

Thus, the Cepheids might provide an intergalactic network of relays, which distant societies could use to broadcast messages to one another. But don't go warming up those neutrinos yet:

[T]he galactic internet would be slow - a Cepheid with a roughly one-day period could transmit about 180 bits per year. Such a transmission would require roughly a millionth of the star's energy, the researchers estimate.

For the time being, it makes more sense to comb through the 100 years' worth of data researchers have collected on the Cephids, searching for irregularities in the pulsing power. Learned estimates:

"Analyzing that data would take a graduate student a couple of months, and just think if it turned out to be correct."

At least the university's indentured academics know how they'll be spending their school year.

'Galactic internet' proposed [Nature]

Researchers at NASA and Germany's Potsdam University observed the Peony nebula star, which by the way is about 100 times wider and 200 times heavier than our familiar sun. NASA offers more images, including a zoomed-in video view, of the Peony nebula at the link below.

Image via NASA/JPL-Caltech/Potsdam Univ.

Brightest Star in the Galaxy Has New Competition [Spitzer Space Telescope @ NASA]

Olson and his colleague Russell Doescher have made a name for themselves pioneering a field they call 'astroforensics.' Poring over historical texts (in this case Caesar's Commentary on the Gallic War), the two piece together bits of astronomical information that were recorded around the time of the event in question — phase of the Moon is a common one, as are the locations of Venus and the Sun, often recorded in paintings. In Shakespeare's "Hamlet" a 'bright star' is mentioned, and that was enough to get Olson thinking that it wasn't a star at all, but a Supernova that lit up the skies in 1572.

Knowing the phase of the Moon, Olson could calculate exact dates when, say, the tides would've been right in 55 BC for Caesar to make his landing near Dover. As it turns out, those same lunar and tidal conditions only present themselves once every few hundred years or so, and August 2007 was one of those dates. So Olson and company went to Dover, chartered a boat, and floated through the English channel, just as Caesar had done. Riding the same currents as the Romans, Olson showed that the evening of Caesar's arrival must have been August 22-23 in the year 55 AD rather than August 26-27, as generations of scholars before him had thought.

Caesar's landing was under duress — thousands of Celtic tribesmen greeted him with arrows and spears. But the Romans prevailed, and began an invasion that would lead to the formation of England.

Not all of Olson's work has as much historical import — he also likes following in the footsteps of Ansel Adams, and predicting when the waterfalls in Yosemite National Park will be moonlit as just the right angle so that their spray produces a rainbow — and he's calculated every time that will happen for the next two years. But CSI's got nothing on this guy, who needs nothing but the night sky to solve his cases.

Source: Sky & Telescope

According to a release from NASA:

"We found a clock that ticks slower and slower, and when it slows down too much, boom! The bomb explodes," says lead author Diego Altamirano of the University of Amsterdam in the Netherlands.

The bursts occur on a neutron star, which is the collapsed remnant of a massive star that exploded in a supernova. The neutron star belongs to a binary system that can be described as a ticking time bomb. Hydrogen and helium gas from a companion star spirals onto the neutron star, slowly accumulating on its surface until it heats up to a critical temperature. Suddenly, the hydrogen and helium begin to fuse uncontrollably into heavier elements, igniting a thermonuclear flame that quickly spreads around the entire star. The resulting explosion appears as a bright flash of X-rays.

These bursts, which can occur several times per day from the same neutron star, release more energy in just 10 to 100 seconds than our Sun radiates in an entire week. Put another way, the energy is equivalent to 100 fifteen-megaton hydrogen bombs exploding simultaneously over each postage-stamp-size patch of the neutron star's surface.

NASA satellite pins down time of explosions [Eurekalert]

The gravity from this cluster of galaxies forms a natural "zoom lens" that lets astronomers view a galaxy that formed just 700 million years after the Big Bang. You can just about glimpse the galaxy A1689-zD1 on the right side of the picture, inside the box. It's one of the youngest and brightest galaxies we've ever seen, formed during the cosmic "dark ages." Researchers believe the dark ages, when stars and galaxies started to form, lasted from 400,000 years to a billion years after the Big Bang — and this new discovery may have been one of the galaxies that helped end that era. [Spitzer Space Telescope]