Crisscrossing Rhea

Crisscrossing Rhea

[SOURCE: saturn.jpl.nasa.gov]

Spitzer Sees Crystal ‘Rain’ in Outer Clouds of Infant Star

Spitzer Sees Crystal 'Rain' in Outer Clouds of Infant Star

PASADENA, Calif. — Tiny crystals of a green mineral called olivine are falling down like rain on a burgeoning star, according to observations from NASA’s Spitzer Space Telescope.

This is the first time such crystals have been observed in the dusty clouds of gas that collapse around forming stars. Astronomers are still debating how the crystals got there, but the most likely culprits are jets of gas blasting away from the embryonic star.

“You need temperatures as hot as lava to make these crystals,” said Tom Megeath of the University of Toledo in Ohio. He is the principal investigator of the research and the second author of a new study appearing in Astrophysical Journal Letters. “We propose that the crystals were cooked up near the surface of the forming star, then carried up into the surrounding cloud where temperatures are much colder, and ultimately fell down again like glitter.”

[SOURCE: spitzer.caltech.edu]

Space Calendar May 30 – June 5 2011

Space related activities and anniversaries for May 30 – June 5 2011. Fetched live every week from NASA JPL

If you want the complete list going more than a year ahead then see the Space Calendar at NASA JPL.

Astronomers Unveil Most Complete 3-D Map of Local Universe

Astronomers Unveil Most Complete 3-D Map of Local Universe

Today, astronomers unveiled the most complete 3-D map of the local universe (out to a distance of 380 million light-years) ever created. Taking more than 10 years to complete, the 2MASS Redshift Survey (2MRS) also is notable for extending closer to the Galactic plane than previous surveys – a region that’s generally obscured by dust.

Karen Masters (University of Portsmouth, UK) presented the new map today in a press conference at the 218th meeting of the American Astronomical Society.

[SOURCE: www.cfa.harward.edu]

The Spitzer Photo Atlas of Galactic “Train Wrecks”

The Spitzer Photo Atlas of Galactic

Five billion years from now, our Milky Way galaxy will collide with the Andromeda galaxy. This will mark a moment of both destruction and creation. The galaxies will lose their separate identities as they merge into one. At the same time, cosmic clouds of gas and dust will smash together, triggering the birth of new stars.

To understand our past and imagine our future, we must understand what happens when galaxies collide. But since galaxy collisions take place over millions to billions of years, we can’t watch a single collision from start to finish. Instead, we must study a variety of colliding galaxies at different stages. By combining recent data from two space telescopes, astronomers are gaining fresh insights into the collision process.

[SOURCE: www.cfa.harward.edu]

NASA’s Hubble Finds Rare Blue Straggler Stars in the Milky Way’s Hub

NASA's Hubble Finds Rare Blue Straggler Stars in the Milky Way's Hub

Probing the star-filled, ancient hub of our Milky Way, NASA’s Hubble Space Telescope has found a rare class of oddball stars called blue stragglers, the first time such objects have been detected within our galaxy’s bulge.

The size and nature of the blue straggler population detected in the bulge will allow astronomers to better understand if the bulge is exclusively old stars, or a mixture of both young and old stars. In addition, the discovery provides a new test case for formation models of the blue stragglers themselves.

Blue stragglers — so named because they seem to be lagging behind in their rate of aging compared with the population from which they formed — were first found inside ancient globular star clusters half a century ago. They have been detected in many globular and open clusters, as well as among the stars in the solar neighborhood. But they have never been seen inside the core of our galaxy until Hubble was trained on the region.

[SOURCE: hubblesite.org]

Five Orbs

Five Orbs

[SOURCE: saturn.jpl.nasa.gov]

How to Learn a Star’s True Age

How to Learn a Star's True Age

For many movie stars, their age is a well-kept secret. In space, the same is true of the actual stars. Like our Sun, most stars look almost the same for most of their lives. So how can we tell if a star is one billion or 10 billion years old? Astronomers may have found a solution – measuring the star’s spin.

“A star’s rotation slows down steadily with time, like a top spinning on a table, and can be used as a clock to determine its age,” says astronomer Soren Meibom of the Harvard-Smithsonian Center for Astrophysics.

Meibom presented his findings today in a press conference at the 218th meeting of the American Astronomical Society.

[SOURCE: www.cfa.harward.edu]

Kepler’s Astounding Haul of Multiple-Planet Systems

Kepler's Astounding Haul of Multiple-Planet Systems

NASA’s Kepler spacecraft is proving itself to be a prolific planet hunter. Within just the first four months of data, astronomers have found evidence for more than 1,200 planetary candidates. Of those, 408 reside in systems containing two or more planets, and most of those look very different than our solar system.

In particular, the Kepler systems with multiple planets are much flatter than our solar system. They have to be for Kepler to spot them. Kepler watches for a planet to cross in front of its star, blocking a tiny fraction of the star’s light. By measuring how much the star dims during such a transit, astronomers can calculate the planet’s size, and by observing the time between successive events they can derive the orbital period – how long it takes the planet to revolve around its star.

[SOURCE: www.cfa.harward.edu]

Hubble Views the Star that Changed the Universe

Hubble Views the Star that Changed the Universe

Though the universe is filled with billions upon billions of stars, the discovery of a single variable star in 1923 altered the course of modern astronomy. And, at least one famous astronomer of the time lamented that the discovery had shattered his world view.

The star goes by the inauspicious name of Hubble variable number one, or V1, and resides in the outer regions of the neighboring Andromeda galaxy, or M31. But in the early 1900s, most astronomers considered the Milky Way a single “island universe” of stars, with nothing observable beyond its boundaries. Andromeda was cataloged as just one of many faint, fuzzy patches of light astronomers called “spiral nebulae.”

Were these spiral nebulae part of the Milky Way or were they independent island universes lying outside our galaxy? Astronomers didn’t know for sure, until Edwin Hubble found a star in Andromeda that brightened and faded in a predictable pattern, like a lighthouse beacon, and identified it as V1, a Cepheid variable. This special type of star had already been proven to be a reliable distance marker within our galaxy.

[SOURCE: hubblesite.org]