US sets dark things as cosmic priorities

This will surely give thrust to the research in dark matter and dark matter:

Over ten years, the US$465-million observatory will also build up an unprecedented 100-petabyte database for astronomers trying to discern the nature of two mysterious factors that shape the Universe. One is dark matter, thought to be an unknown particle or family of particles beyond the standard model of physics. Hidden in vast quantities among the galaxies, dark matter generates a gravitational pull that has shaped the evolution of the Universe. The other factor is dark energy, the pervasive but mysterious phenomenon that is causing cosmic expansion to accelerate. Crucial data on both factors can be derived from a three-dimensional survey of the surrounding Universe that the LSST is well suited to provide.

“Increasingly, we are able to ask new questions by querying huge databases.”

"Increasingly, we are able to ask new questions by querying huge databases," says Tyson. "The key is to populate those databases with calibrated and trusted data."

The LSST is expected to help US astronomers regain some momentum in ground-based astronomy at a time when European facilities have begun to dominate the field. To that end, the survey stresses the need for a swift decision on which of two competing mega-telescopes should receive federal funding.

The proposed Thirty Meter Telescope, on Mauna Kea in Hawaii, and the Giant Magellan Telescope, envisioned for Las Campanas in Chile, are both supported by significant private money, and would have many times the light-gathering power and resolution of today's largest telescopes. Realistically, only one project will receive federal funds, which the survey recommends should be between $257 million and $350 million. Given that Europe has also prioritized a 42-metre telescope, the European Extremely Large Telescope, a choice needs to be made now to avoid a counterproductive stalemate.

In space, the decadal survey proposes the Wide Field Infrared Survey Telescope (WFIRST), a 1.5-metre instrument that will map the whole sky at near-infrared wavelengths. Such data would contain subtle clues — in the distance–brightness relationships of supernovae, the bending of light (microlensing) from background galaxies and the three-dimensional clustering of matter in space — that can be used to independently measure dark energy.

WFIRST is effectively a rebranding of the Joint Dark Energy Mission, a NASA–DOE collaboration. The new name, says one survey reviewer, signals that the $1.6-billion telescope is not a one-trick pony, but a way of serving other astronomical needs as well. The survey committee stresses, for example, that WFIRST could spot microlensing events caused when exoplanets — planets outside our Solar System — pass briefly in front of background stars in the Milky Way. Although the method is unsuitable for studying individual solar systems in detail, it promises, through its sheer number of discoveries, to provide an unbiased sample of the kinds of planetary systems prevalent in the Galaxy.