No X-ray telescopes, but how about dark energy telescopes?

An artist's rendition of the GEMS X-ray telescope. Courtesy of www.nasa.gov

Astronomy has been a hot topic the past week. Venus aside, NASA is planning on scrapping one project but might look into using some old spy toys.

That first bit of unfortunate news comes from a budget review of the Gravity and Extreme Magnetism Small Explorer X-ray telescope, GEMS for short, which was projected to cost 20-30% more than the maximum of $135 million set by NASA. So far the project has cost NASA $43.5 million and the decision to terminate it will cost it another $13 million. Scientists involved in the project had appealed the decision today.

GEMS was designed to study regions around black holes and neutron stars by studying the bent X-ray light coming from these extremely mass-dense objects. The driving force of the increased costs of the project were the challenges in developing some of the technologies that would have gone into the telescopes. There goes one new toy that could have gone up into orbit in a few years.

If that decision is final, there's still another new set of telescopes NASA can work with, or rather they are a set of oldies acquired from the National Reconnaisance Office. In a plan presented at the National Academy of Sciences to the public by physicist and former astronaut John Grunsfeld, NASA could use these telescopes, which they had acquired last year, to study dark matter.

To be brief on the details of these telescopes, they were meant to be spy satellites and have a shorter focal length than what would be needed to do what the Hubble does, among other properties setting it apart from a space telescope. However, some of those features are fairly close what a telescope would need to study dark matter. With much of the hardware in place, re-purposing one of these relics could save NASA a lot of money over a similar project starting from scratch, but given NASA's impulsiveness to cancel GEMS over a cost infraction, it's tough to say whether they would go forward with this plan and appropriate the funds. In addition, the launch of this possible telescope would not occur until after 2020, years after Hubble is expected to be decommissioned and its replacement, the big-ticket James Webb Space Telescope, to be in orbit.

In case you missed something else about Hubble from last week, NASA astronomers are predicting a collision between two galaxies: our Milky Way and Andromeda. Before you start scrambling to buy galactic collision insurance — or become a con artist — it's not going to actually happen for about four billion years. Chances are nothing physically will collide within the Andromeda galaxy and ours, given the vast stretches of "empty space" (dark matter for the more astronomically informed) permeating between stars and planets.

The big thing that the denizens of Earth will notice four billion years from now is a massive change in the night sky, at least compared to today, where the lights of Andromeda's stars will seem a whole lot brighter.

—Ian Yu, Managing Editor