SpaceJibe

December 19, 2008

‘Wet’ Early Universe: Water Vapor Detected At Record Distance

Filed under: Black Holes, Cosmology — bferrari @ 7:52 pm

CFHT, J.-C. Cuillandre, Coelum)

Discovery spectrum (insert upper right) showing water maser emission from the quasar MG J0414+0534 with high redshift. The background image, an HST near infrared image of the quasar, shows how the quasar appears broken up into four components by a foreground galaxy (diffuse source in the centre), acting as a gravitational lens and strengthening the signal by a factor of 35. The inset (lower right) with galaxy M87 shows how the quasar could be seen from nearby. (Credit: Milde Science Communication, Background Image: HST Archive data, Inset: CFHT, J.-C. Cuillandre, Coelum)

ScienceDaily (Dec. 19, 2008) — A research group led by graduate student Violette Impellizzeri from the Max Planck Institute for Radio Astronomy has used the 100 m Effelsberg radio telescope to detect water at the greatest distance from Earth so far. The water vapour was discovered in the quasar MG J0414+0534 at redshift 2.64, which corresponds to a light travel time of 11.1 billion years, a time when the Universe was only a fifth of the age it is today.

The water vapour is thought to exist in clouds of dust and gas that feed the supermassive black hole at the centre of the distant quasar. The detection was later confirmed by high-resolution interferometric observations with the Expanded Very Large Array.

The discovery of water in the early Universe was possible only due to the chance alignment of a foreground galaxy and the distant quasar MG J0414+0534. The foreground galaxy acts like a cosmic telescope, magnifying and distorting the light from the quasar forming four distinct images of the quasar. Without this gravitational lensing effect, 580 days of continuous observations with the 100 m telescope would have been needed instead of the 14 hours used to make this remarkable discovery. “Others have tried and failed to find water, and we knew we were looking for a very faint signal”, says Violette Impellizzeri, “so we thought of using a foreground galaxy like a cosmic magnifying glass to observe at a far greater distance and had to be persistent, and sure enough the line emission of water popped up.”

The detection of water from MG J0414+0534 with the Effelsberg radio telescope also occurred thanks to a touch of fortune. The object is within just the right redshift interval to stretch the line emission of the H2O molecule from its original frequency of 22 GHz to 6 GHz and so within the tuning range of the 6 GHz receiver installed at the telescope.

“It is interesting that we found water in the first gravitationally-magnified object we observed from the distant Universe”, says co-author John McKean. “This suggests that the water molecule may have been much more abundant in the early Universe than first thought, and can be used for further research into supermassive black holes and galaxy evolution at high redshift.”

The water emission was seen in the form of a maser, that is, beamed radiation similar to a laser, but at microwaves wavelengths. The signal corresponds to a luminosity of 10,000 times the luminosity of the Sun. Such astrophysical masers are known to originate in regions of hot and dense dust and gas. With the detection of water from MG J0414+0534 it is the first time such a dense gas component has been observed in the early Universe and shows that the conditions for the water molecule to form and survive already existed only 2.5 billion years after the Big Bang.

The story continues here: http://www.sciencedaily.com/releases/2008/12/081218122244.htm

Advertisements

Leave a Comment »

No comments yet.

RSS feed for comments on this post. TrackBack URI

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

Blog at WordPress.com.

%d bloggers like this: