Home > Astronomy, Astrophysics, Galaxies, General Astronomy, Quasars > Intergalactic Magnifying Glasses Could Help Astronomers Map Galaxy Centres

Intergalactic Magnifying Glasses Could Help Astronomers Map Galaxy Centres


An international team of astronomers may have found a new way to map quasars, the energetic and luminous central regions typically found in distant galaxies. Team leader Prof. Andy Lawrence of the Royal Observatory Edinburgh presents the new results on Monday 1 July at the RAS National Astronomy Meeting in St Andrews, Scotland.

If a star passes too close to a giant black hole found in the centre of a galaxy, it will be shredded by the strong gravitational field. This should produce a flare-up in the brightness of an otherwise normal looking galaxy that then fades over a few months. In a large scale survey Prof. Lawrence and his team studied galaxies to search for this effect, finding flare-ups but with very different behaviour to predictions.

In the new survey, the quasars are typically around 8 billion light years away, whereas the galaxies that host them are 3.4 billion light years distant. It could be that the estimated galaxy distances are wrong and that the black holes in the centre of the galaxies have flared up dramatically. But past studies of thousands of well known quasars have never shown events on this scale.

If however the estimated galaxy distances are right, then Prof. Lawrence and his team believe they are looking at a distant quasar through a foreground galaxy. Normally this has little effect on the light of the quasar, but if a single star in the foreground galaxy passes exactly in front of the quasar, it can produce a gravitational focusing of the light which makes the background quasar seem temporarily much brighter.

Full Story: http://www.ras.org.uk/news-and-press/224-news-2013/2296-intergalactic-magnifying-glasses-could-help-astronomers-map-galaxy-centres

Advertisements
  1. No comments yet.
  1. No trackbacks yet.

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

%d bloggers like this: