The result of the mapping provide conclusive evidence that dark matter was the foundation for regular matter to group together and form galaxies, and clusters of galaxies.
"Dark Matter" is a form of matter that is completely undetectable with conventional means,
the reason for it to first to become theoretically apparent was due to the gravitational pull it exerts on other objects.
the study has been a long time coming, Hubble has dedicated 10% of its time over two years (approx. 1,000 hours) to complete the survey of the patch of sky being mapped,
as one would imagine, in the scheme of things this has been a fairly massive undertaking.
other telescopes have been involved in parts of the mapping including the Subaru telescope at the top of Mauna Kea and the VLT in Paranl which were used to calculate the distances' of the galaxes, along with the XMM-Newton X-RAY satellite used to map gas with galaxies and galactic clusters.
the period covered by the mapping is between 3.5 and 6.5 billion years ago.
there are still many discrepancies that are yet to be cleared up, and although there are many suggestions, along with the point that the discrepancies may not even exist there is insufficient data to ascertain this at this point in time,
more data is being collected which should enable further clarification.
bbc news provided a great analogy to many of the problems faced by astronomers trying to map the universe,
"For Astronomers, the challenge of mapping the Universe has been described as similar to mapping a city from night-time aerial snapshots showing only street lights"
I think that provides a great verbal illustration.
Other related posts:
ESA calling for voluteers for Mission to Mars
Bizarre hexagon shape on saturn.
INSAT-4B Launched Successfully
Comment by KJ, on 9-Jan-2007 15:05
Heh, Imagine using those pics as the pattern on that new laminate flooring you can get where you can put your own pictures into it.... Dark matter flooring! Just don't look too closely at it while drunk...