Despite being among the brightest and easily identified clusters in the night sky, the trio of stars in Orion's Belt are actually among the least studied in astronomy. That's partly because the huge, far-seeing telescopes typically sent into space are designed to spot only the dimmest, most distant stars. But Orion's Belt will finally get its day in the sun with today's launch of a pair of tiny telescopes—the smallest to ever gaze into the heavens.
Dubbed the BRIght Target Explorer (BRITE), these two telescopes are each packed into separate 20cm ( 7.9-inch) cubes that weight about 17 pounds each. You can't very well fit something as acute as the Hubble into such a miniscule form factor. Instead, these nano-satellites are designed to track and record changes in these large stars' relative brightness levels. As such, the BRITES are equipped with low-end CCD photometers capturing light from 3cm dioptic telescopes with one BRITE sensitive to the red band of light, the other to blue band. This certainly doesn't sound very impressive but the BRITE satellite constellation is expected to deliver more and better-quality images than those of larger, ground-based observatories, focusing on asteroseismology (the study of the internal structures of pulsating stars).
Developed as part of the CanX-3 program at the Space Flight Laboratory (SFL) of the University of Toronto Institute of Aerospace Studies (UTIAS) in Toronto, Canada, the BRITE nano-satellites are designed to be easy to assemble and inexpensive to launch. They're orbit-agnostic, meaning they can observe their target stars regardless of the orbit they're in (and therefore don't need to be nudged into place by expensive rockets). Launching today from Satish Dhawan Space Centre in Sriharikota, India, the Polar Satellite Launch Vehicle C20 will simply drop them wherever once it leaves the atmosphere.
"SFL has demonstrated that nano-satellites can be developed quickly, by a small team and at a cost that is within reach of many universities, small companies and other organizations," says Cordell Grant, Manager of Satellite Systems for the Space Flight Laboratory at UTIAS. "A nano-satellite can take anywhere from six months to a few years to develop and test, but we typically aim for two years or less."
The BRITE program is not only the first nano-satellite system designed for astronomy (many other nano-sats have been launched previously but have been exclusively for Earth sciences) it is also the first system to work as a constellation. If successful, UTIAS officials hope the technology will help usher in an era of low cost, high-power nano-satellites as scientific platforms.