Ireland has been urged to become involved in a new international space observation project that will study ultraviolet radiation, writes John Moore.
Astronomers throughout the world are losing the ability to see objects at the ultraviolet end of the spectrum, researchers have warned. Ageing telescopes will soon mean scientists will not be able to read ultraviolet wavelengths coming in from space.
A Trinity College Dublin astronomer specialising in UV wavelength observation will tomorrow propose a way to reverse this situation, however. Dr Brian Espey is scheduled to tell a meeting of astronomers he believes the Republic should join a world consortium planning to build a new UV observatory.
Seeing astronomical objects in ultraviolet light helps astronomers understand better how our universe works. As most of this light is absorbed by the Earth's atmosphere, the observations have to be made from space using orbiting observatories.
As one of the main UV orbiting observatories on board the Hubble Space Telescope failed just a month ago, and the remaining observatories with UV capability are about to reach retirement age soon, astronomers are getting worried that they'll soon have no way of observing UV light.
Espey, of Trinity's physics department, will tomorrow address the Astronomical Science Group of Ireland (ASGI) general meeting at University College Dublin. He will outline a set of proposals that UV astronomers like him might take to solve the problem.
"One of those proposals could fill the UV gap in the future," says Espey. "It includes Ireland joining a global consortium of countries in a project to build a World Space Observatory (WSO)."
Right now two main satellites scan the UV skies. The Far-Ultraviolet Spectroscopic Explorer (FUSE), which Espey uses, is currently providing high-resolution spectra of faint objects, while the Galaxy Evolution Explorer (GALEX) is carrying out an all-sky survey of over a million galaxies.
FUSE is already two years passed its mission lifetime and GALEX is expected to finish in 2005. Astronomers also had access to the STIS (Space Telescope Imaging Spectrograph) instrument fitted on board NASA's Hubble but that device failed last month.
NASA previously planned a shuttle mission to upgrade Hubble and replace STIS with another spectrograph called the COS (Cosmic Origins Spectrograph), however, last January they decided to cancel it, stating astronaut safety as the reason.
"What's happened now will maybe leave us blind for possibly 10 years," says Dr Simon Jeffery of the Armagh Observatory who will also be attending the UCD meeting tomorrow. "There's really nothing concrete planned that has solid funding backing." Jeffery will outline proposals that the UK Particle Physics and Astronomy Research Council and the European Space Agency might bring forward plans to finance a UV mission, possibly the WSO. The estimated cost of building the WSO would be in the region of $250 (€207) million. The observatory would have a mirror 1.7 metres in diameter, and would be 40 to 50 times sharper than the Hubble device. It could be launched some time between 2007 and 2010.
Already about 20 countries are interested in joining and each would be expected to make "in-kind" contributions of expertise, finance or hardware. The Russians are planning to contribute telescope technology, while the Germans might contribute a spectrograph.
"There is an outside chance that one of our institutions building space instrument here could help in that way also," says Espey. "What we mainly need right now, however, is agreement, and hopefully something set in stone or agreed upon on what we intend to do for the future."
The ASGI meeting will be held in Lecture Theatre C in the Science Block starting at about 10 a.m. tomorrow.
See http://fuse.pha.jhu.edu and http://wso.vilspa.esa.es