CANADA-FRANCE-HAWAII TELESCOPE / 2003|
The largest camera in the world on a telescope, MegaPrime, is operating on Mauna Kea. The upper end is installed on the top ring of the telescope, and the rest of MegaPrime is protected by a cover, seen in the picture as a black and silver structure.
New Mauna Kea camera
sees big picture
The wide-field device helps researchers
investigate broad expanses of the sky
By Helen Altonn
The largest camera in the world on a telescope is operating now on one of the oldest observatories on Mauna Kea, the Canada-France-Hawaii Telescope.
"Its field of view, the amount you can see in the sky, is basically four times bigger than any camera in the world," said University of Hawaii astronomer Scott Sheppard.
Working with the new MegaPrime instrument in recent months, Sheppard and David Jewitt, a colleague in the UH Institute for Astronomy, and associates have discovered a number of new satellites around Jupiter.
The Canada-France-Hawaii Telescope, with a 3.6-meter mirror, appears small compared with its giant 8- to 10-meter neighbors on the Big Island mountain, said Christian Veillet, MegaPrime executive director and project manager.
However, he said the CFHT "has been heavily used for a lot of good science" and is not out of date.
"With the new camera, we are one step further," he said. The telescope will be competitive for many years with the camera putting it in the forefront of optical astronomy, he said.
"It is definitely the largest one by a good margin for people to be able to observe a large area of the sky at once."
MegaPrime was in development six years in a collaboration between CFHT, French and Canadian institutes and industrial contractors.
MegaPrime gives astronomers a field of view of 1 degree by 1 degree -- the size of four full moons.
Built atop the telescope, MegaPrime has specially designed optics and a 340-megapixel digital camera made in France called MegaCam.
Sheppard said the instrument can be used to do wide-field imaging for all astronomy.
Instead of taking a series of pictures and putting them together to get a panoramic view, he explained, only one or two images are needed with a camera as big as MegaPrime.
Observations of large blocks of sky at very high resolution will allow scientists to see details of millions of faint objects.
They will be able to look for small objects around planets or on the outskirts of the solar system, watch dying stars explode in remote galaxies, study ripples of space due to unseen matter or detect new phenomena.
Veillet said scientists have been taking a lot of pictures to fine-tune the camera. "We're very close now to the final configuration, so the coming month, we'll be working for science, mainly."
UH astronomers and a team in Canada were the first to use the camera to look at moons of Jupiter, he said.
They announced last month that they had found seven new moons circling Jupiter, raising the total to 47.
"Because it's such a wide field of view, it allows us to search the area around Jupiter more efficiently," Sheppard said.
"In one night with the camera, we could search the whole area. With another camera it would take four or more nights to do it."
The CFHT had been pioneering with the use of large detectors through a series of mosaics. The last one, in use the past four years, was made of 12 Charge Coupled Devices, the silicon chips used in digital cameras.
It was the largest contiguous mosaic in use on an astronomical telescope and produced "amazing pictures," according to a description of the telescope.
But MegaPrime is expected to open a new era in wide-field imaging of the sky.
Veillet said the CFHT is in a unique position that complements bigger telescopes on Mauna Kea with a narrow field of view, and they work collaboratively.
"It is very important us to have kind of a niche and provide something others can't."