Cosmic Beacon Images

Here we show the distribution of quasars from the 2dF survey.  Our galaxy is situated at the centre of the plot.  Each point represents a quasar.  The low density radial strips are regions which are yet to be observed.  With the 2dF survey we can detect quasars to distances of about  14 billion light years.
 

A summary of redshift surveys that have been used to measure structure in the Universe.  We show the number of objects (either quasars or galaxies) in each survey verses the volume of the Universe that the survey covers. The volume is calculated assuming a cosmological model with a critical density (Omega_0=1).  The extreme luminosity of quasars allows us to survey a much larger (up to a factor of ~100) volume of the Universe than is possible with normal galaxies. The 2dF QSO Redshift Survey (2QZ) is indicated in red.

A visual representation of all the data in the survey.  Each horizontal line is the spectrum of one quasar, with the blue (short wavelength) end to the left and the red (long wavelength) end to right.  The spectra are ordered vertically by increasing redshift.  Thus, the strong features seen in the spectra of the quasars can be seen to move redwards (right) at higher redshift (top). The vertical features are due the absorption of
quasar light by the earth's atmosphere.

The 2-degree Field instrument on top of the Anglo-Australian Telescope.

For low resolution image click here.
For high resolution image click here.

The 2dF robotic fibre positioner in action.  Each red dot is the end of a back illuminated optical fibre.  The robot grabs each fibre in turn, positioning them to match the position of objects on the sky.  Each fibre is positioned to within 0.01mm in less than six seconds per fibre.

For low resolution image click here.
For high resolution image click here.

The density of quasars surveyed with 2dF in our Universe.  The circle defines the limits of the observable Universe (assuming omega_0=1). Our galaxy is at the centre of the sphere.  The low density radial strips are regions which are yet to be observed.