In a worrying development from the past week, a satellite slated to advance our understanding of dark energy just got zeroed out of NASA's budget.
The modern version of the story began in 1998/1999 with the announcement that supernovae at great distances are fainter than they ought to be. The interpretation of this measurement is that the universe is accelerating away from us.
This discovery resulted in a Nobel Prize for three U. S. scientists, one of whom was an undergraduate peer of mine at the University of Arizona by the name of Brian Schmidt!
As exciting as it was, the discovery was also bizarre and unexpected. Up until that time we had thought that the universe merely expanded like a balloon until it reached a maximum extent, and then closed back in on itself.
The discovery of dark energy, on the other hand, means that the universe is accelerating away from itself. In this sense dark energy gives us literally a dark future as the galaxies eventually will get so far apart that we will no longer see them in the night sky.
For the past 20 years astronomers have been trying to build a satellite to characterize this mysterious dark energy. The answer is a new space telescope, called WFIRST, which will have an aperture the same size as the famous Hubble Space Telescope. As an advantage, WFIRST will also have an outer barrel assembly salvaged from a former government satellite.
WFIRST, which could make exquisite observations of distant supernovae to inform our understanding of dark energy, was to launch in the mid-2020s. Now that it has just been zeroed out, NASA will have to take up new negotiations at the level of Congress to reinstate the project that will teach us the fate of our own universe.