Researchers from Imperial College London and the University of Barcelona have used data from astronomical surveys to measure a standard distance that is central to our understanding of the expansion of the universe, a much more accurate method than calculations related to general relativity. 

The new study is the first to measure it using observed data. A standard ruler is an object which consistently has the same physical size so that a comparison of its actual size to its size in the sky will provide a measurement of its distance to earth.  Previously the size of this standard ruler has only been predicted from hypothetical models that rely on general relativity to explain gravity at large scales. 

Titan is Saturn's largest moon and the only planetary body outside Venus, Earth and Mars to have fields of wind-blown dunes on its surface.

Undiscovered Worlds and Pale Blue Dots

May 9th 2015 will see the inauguration of Cornell University's new Institute for Pale Blue DotsDetails here.

The first image of a "pale blue dot" was sent back by Voyager 1.  The "dot" is a single pixel.

"all of human history has happened on that tiny pixel, which is our only home"
Carl Sagan, speech at Cornell University, October 13th 1994
Why does the new space craft look like a capsule?  The simple fact is that between a capsule and a space plane like the shuttle, a capsule is the better vehicle for a direct return trip from interplanetary space to Earths surface. 
People my age, early-mid 30's, and younger look at a space capsule as being an artifact from a past era.  The 1960's and 1970's were the age of the capsule.  Then in the 1980's and 1990's we had the Space Shuttle Program in full swing.  The shuttle was so much more than a spacecraft.  As president Reagan put it the Shuttle was a symbol of our aspirations for freedom. 

In the below it can be said that he dedicated a Shuttle launch to people who 20 years latter would become the Taliban.