Feeds

Galactic spring-clean unveils missing quasars

Kim 'n Aggie would be proud

  • alert
  • submit to reddit

The smart choice: opportunity from uncertainty

A team of astronomers might have solved one of the mysteries of astrophysics with the discovery of a clutch of quasars, hiding behind clouds of dust. The discovery was made using data from NASA's Spitzer Space Telescope, and could explain previously mysterious levels of cosmic background radiation.

Quasars are very distant, but very strong sources of radio signals. The working theory is that they are located in the central cores of very distant galaxies, where matter falling into a supermassive black hole is turned into a blinding torrent of radiation.

Astronomers suspect that all quasars are surrounded by a dusty ring, and that this hides about half of them from our Earth-based line of sight. However, the cosmic X-ray background, primarily made up of emissions from quasars, suggests that there must be many more of the voracious objects than could be accounted for by those currently known about.

Examining data from Spitzer, the team found 21 examples of these lost quasars, hidden behind both a dust ring, and the dust of the galaxy itself. The objects were confirmed as quasars by the National Radio Astronomy Observatory's Very Large Array radio telescope, New Mexico, and the William Hershel Telescope on La Palma.

Alejo Martinez-Sansigre from the University of Oxford noted: "We were missing a large population of obscured quasars, which had been inferred from studies at X-ray frequencies. This newly discovered population is large enough to account for the X-ray background."

The trick now, he says, will be to work out why there are more hidden quasars than unobscured ones. ®

Related stories

Hubble sends back new pictures to mark 15 years in orbit
Life on earth follows 62 million year cycle
First galaxies arrived early, and overweight
Galactic prang fingered in star formation mystery
Astronomers spot first ever dark galaxy

Eight steps to building an HP BladeSystem

More from The Register

next story
Malaysian Airlines flight MH17 claimed lives of HIV/AIDS cure scientists
Researchers, advocates, health workers among those on shot-down plane
Mwa-ha-ha-ha! Eccentric billionaire Musk gets his PRIVATE SPACEPORT
In the Lone Star State, perhaps appropriately enough
MARS NEEDS OCEANS to support life - and so do exoplanets
Just being in the Goldilocks zone doesn't mean there'll be anyone to eat the porridge
The Sun took a day off last week and made NO sunspots
Someone needs to get that lazy star cooking again before things get cold around here
Diary note: Pluto's close-up is a year from … now!
New Horizons is less than a year from the dwarf planet
Boffins discuss AI space program at hush-hush IARPA confab
IBM, MIT, plenty of others invited to fill Uncle Sam's spy toolchest, but where's Google?
prev story

Whitepapers

Seven Steps to Software Security
Seven practical steps you can begin to take today to secure your applications and prevent the damages a successful cyber-attack can cause.
Consolidation: The Foundation for IT Business Transformation
In this whitepaper learn how effective consolidation of IT and business resources can enable multiple, meaningful business benefits.
Designing a Defense for Mobile Applications
Learn about the various considerations for defending mobile applications - from the application architecture itself to the myriad testing technologies.
Build a business case: developing custom apps
Learn how to maximize the value of custom applications by accelerating and simplifying their development.
Consolidation: the foundation for IT and business transformation
In this whitepaper learn how effective consolidation of IT and business resources can enable multiple, meaningful business benefits.