Feeds

Dim stars shed light on age of galaxy

Beryllium count gives the game away

  • alert
  • submit to reddit

Top three mobile application threats

A group of astronomers working on the Very Large Telescope (VLT) in Chile have determined that the galaxy is 13.6bn years old.

Its calculation of the age of the Milky Way is based on observations of two very faint stars in a local globular cluster, the BBC reports. Globular clusters are very concentrated clusters of stars which orbit galaxies, and contain some of the oldest stars still burning.

By measuring the amount of beryllium in each of the stars, the astronomers could calculate their age, since the element forms at a constant rate as stars burn. The team made its observations ib the 8.2m Kuyen telescope that is part of the VLT, using the UV-Visual Echelle Spectrograph.

Incidentally, some scientists think globular clusters may actually be remnants of smaller "dwarf" galaxies, caught in the gravitational maw of their larger counterparts. The implications this theory may have for these calculations is unclear.

The team carefully selected the stars they would measure, known as A0228 and A2111 in the NGC 6397 globular cluster. Star selection is vital because beryllium will burn up if the star has become too hot, making it useless as a benchmark.

Smaller stars are best, but are difficult to observe because they are so faint. Many of the larger stars, which burn faster and hotter, have already reached the giant phase of their evolution.

It is well known that the stars in globular clusters were not the first stars that ever burned in our galaxy: they contain elements that need supernovae to form. However, this new research has allowed scientists to calculate the interval between the first (now extinct) generation of stars and the ones we can still observe today.

By adding this number to the age of the stars, as determined by stellar evolution models, the team determined that the galaxy is 13.6bn years old, give or take 800m years.

Daniele Galli of INAF-Observatorio di Arcetri in Florence, Italy, told the BBC: "This is the first time we have obtained an independent determination of this fundamental value." ®

Related stories

Hubble loses an eye
Boffins baffled by suburban quasars
NASA seeks Hubble robot rescue input

High performance access to file storage

More from The Register

next story
Most Americans doubt Big Bang, not too sure about evolution, climate change – survey
Science no match for religion, politics, business interests
KILLER SPONGES menacing California coastline
Surfers are safe, crustaceans less so
Discovery time for 200m WONDER MATERIALS shaved from 4 MILLENNIA... to 4 years
Alloy, Alloy: Boffins in speed-classification breakthrough
LOHAN and the amazing technicolor spaceplane
Our Vulture 2 livery is wrapped, and it's les noix du mutt
Liftoff! SpaceX Falcon 9 lifts Dragon on third resupply mission to ISS
SpaceX snaps smartly into one-second launch window
R.I.P. LADEE: Probe smashes into lunar surface at 3,600mph
Swan dive signs off successful science mission
Opportunity selfie: Martian winds have given the spunky ol' rover a spring cleaning
Power levels up 70 per cent as the rover keeps on truckin'
Elon Musk's LEAKY THRUSTER gas stalls Space Station supply run
Helium seeps from Falcon 9 first stage, delays new legs for NASA robonaut
prev story

Whitepapers

Mainstay ROI - Does application security pay?
In this whitepaper learn how you and your enterprise might benefit from better software security.
Combat fraud and increase customer satisfaction
Based on their experience using HP ArcSight Enterprise Security Manager for IT security operations, Finansbank moved to HP ArcSight ESM for fraud management.
The benefits of software based PBX
Why you should break free from your proprietary PBX and how to leverage your existing server hardware.
Top three mobile application threats
Learn about three of the top mobile application security threats facing businesses today and recommendations on how to mitigate the risk.
3 Big data security analytics techniques
Applying these Big Data security analytics techniques can help you make your business safer by detecting attacks early, before significant damage is done.