CASCA/UBC: The BRITE Constellation Satellite Mission
The smallest space telescopes in the history of the Space Age will soon start unlocking the secrets of the largest stars in the history of the universe.
BRITE Constellation represents new frontiers in aerospace technology and astrophysical science. BRITE stands for “BRIght Target Explorer,” because the targets in the sky for this mission are the most luminous stars in our galaxy. It’s a “constellation” because there will eventually be six BRITE satellites in orbit, monitoring the sky regularly for years to come.
Each BRITE satellite — about the size and mass of a car battery — houses a small optical telescope feeding a CCD detector. Canadian aerospace technology is at the heart of the BRITE design, and Canadian astronomers have partnered with colleagues in Austria and Poland to make the mission a reality. Each country is contributing a set of twins to the planned sextuplet of satellites. The first two BRITE nanosatellites were launched in late February, and it’s expected all six will be in orbit by the end of 2014.
How can such small satellites tackle big questions in astrophysics?
Focusing on the brightest stars in the sky, visible on a clear dark night with the unaided eye, the tiny BRITE eyes will measure subtle changes in the brightnesses of these stars. The changes can be oscillations in brightness due to actual physical vibrations of the star, which astronomers translate into the otherwise hidden internal structure through a technique called stellar seismology. The changes can be due to spots on the stars’ surfaces — bad complexions which alternate between ‘breakouts’ and ‘clear skin’, like our Sun’s 11-year sunspot activity cycle. The changes can also be due to ejections of gas from a star’s surface, like the Sun’s wind and its flares.
Sometimes the changes are not due to the star itself, but caused by a planet passing in front of the star, causing dips in the star’s apparent brightness.
BRITE Constellation will capture all these types of changes in hundreds of stars to be monitored, and the mission is expected to discover new planets.
The brightest stars you see when you look up at night happen to be among the truly brightest stars in the galaxy.
Some are stars many times the mass of the Sun, which will soon die in spectacular supernova explosions. (To an astronomer, “soon” can mean millions of years from now, but in some cases, maybe only centuries. Or maybe it’s happened to one of these stars, but the light signal of the explosion is still en route to Earth.)
These massive stars are currently shedding gas into space through powerful high-speed “winds.” Those winds, and the eventual supernova explosions when these stars die, are how the raw materials that made the Earth — and us — were injected into space to become the ingredients of later generations of stars and planets. By studying the vibrations and the winds of these stars, the BRITE team will shed new light on how the atoms in your body were created and distributed throughout interstellar space.
Many of the brightest stars in the Earth’s night sky not massive stars, but red giants and supergiants, hundreds of times the diameter of our Sun. They are examples of other suns in the galaxy approaching their own deaths. They are dying not with a bang, like the massive stars, but with a whimper. This is the future fate of our own Sun, and BRITE data will help astronomers revise their version of the final chapters in the biography of our home star.
Press Contacts:
Leslie Sage
CASCA Press Officer
+1 301-675-8957
cascapressofficer@gmail.com
Chris Balma
Director, UBC Science Communications
+1 604-822-5082
balma@science.ubc.ca
Science Contact:
Prof. Jaymie Matthews
University of British Columbia
+1 604-822-2696
matthews@astro.ubc.ca
Prof. Jaymie Matthews (University of British Columbia), a member of the BRITE Executive Science Team, will describe the BRITE Constellation mission and its scientific goals to fellow astronomers during his talk at the annual meeting of CASCA (the Canadian Astronomical Society / Societe d’Astronomie Canadienne) at the University of British Columbia, at 12:15 pm PDT on Tuesday, 28 May 2013. Details of the CASCA 2013 meeting can be found at http://casca2013.phas.ubc.ca/
