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PUKALANI Atop the summit of Haleakala, the world's largest digital camera is taking pictures of the night sky as part of a sky-surveying project to detect space objects that could threaten Earth.

Just the first phase of a state-of-the-art astronomy research program, the Panoramic Survey Telescope And Rapid Response System - Pan-STARRS - is the first of the next generation of sky surveying systems.

Its purpose could be significant to the future of the Earth as well - to identify and track objects in the solar system, asteroids and comets whose orbits could bring them uncomfortably close to Earth. The 1.8-meter telescope set up for the Haleakala Pan-STARRS is relatively small compared to the 4-meter and larger mirrors installed for cosmology research across the channel on Mauna Kea.

The design of the Pan-STARRS system is unique, according to Mike Maberry, associate director for external affairs with the University of Hawaii Institute for Astronomy.

Rather than having a single camera and giant telescope pointed into the night sky, the complete Pan-STARRS will utilize four cameras and telescopes all aligned and coordinated as PS1, PS2, PS3 and PS4 in a single observatory.

"The general idea is to have four cameras and four telescopes looking at the same spot in the sky," Maberry said.

By overlapping the four separate images, scientists will be able to monitor any kind of moving object in space, including and especially asteroids and comets - objects that can trace tracks that can run them into the Earth.

"By doing so we can sort of create movies of what the night sky looks like over the period of a decade," said Robert Jedicke, an IfA specialist on the Pan-STARRS project. "It really allows us to observe not only things that are stationary in the sky, like stars and galaxies, but also those things that move or change."

PS1, the first phase on Haleakala, is considered a prototype for the larger four-part system and is up and observing although it still is in a calibration phase.

"It's kind of like a test bed for the final system," said Nick Kaiser, associate director of national telescopes and Pan-STARRS' principal investigator, "It's a full-scale telescope with full-scale camera and it has all of the software we need to process the huge amounts of data that we generate."

PS1's imaging system will be operated from Maikalani, the IfA research center in Pukalani. According to Kaiser, it will work "in the same way that a commercial digital camera works."

The camera on PS1 can take a 1.44 gigapixel picture of the night sky - each image made up of 1.44 billion pixels. By comparison, a picture taken from a typical home digital camera may be five megapixels, or 5 million pixels. The images taken by PS1 will be roughly 280 times sharper and more detailed than the pictures from the 5-mp camera.

The cameras cost more than 280 times the price of a home camera - somewhere between $1 million and $5 million.

The detail allowed by the PS1 camera should allow Pan-STARRS researchers to detect dimly lit rocks just yards across and other faint objects spinning through the solar system.

The telescopes will have a 3-degree view of the night sky, which Maberry said is extremely wide for a telescope.

"What's amazing about Pan-STARRS is that it's got this amazing field of view," said Kaiser. "We can observe a region which is 40 times the area of the full moon in a single exposure."

"The power of Pan-STARRS is not in its magnification but in the area which it can cover and how faint we can detect objects," said Jedicke.

Kaiser said Pan-STARRS will scan the entire sky visible from Haleakala.

"We're going to be building up this incredible digital atlas of the entire sky, a sort of multicolored image of the entire sky, and also what we'll be doing is monitoring anything that moves or changes while we're doing this," he said.

It can also detect other phenomena such as supernovae or exploding stars as it scans, although the distant objects will be better seen by other observatories.

"We're going to detect upwards of a billion stars and roughly a billion galaxies," Kaiser said.

Maberry explained that the images from the Haleakala summit will be transferred to the Maui High Performance Computing Center in Kihei, where the data will be analyzed, sharpened, cleaned up, processed and catalogued. The digital data will then go to the IfA's Database and Moving Object Processing System in Manoa, where it will be analyzed further.

The data will then be sent out to the PS1 Science Consortium, the cooperating research institutions that will subject the data to even more searching questions.

PS1 Science Consortium is a collaborative effort involving universities and research institutions around the globe, with the UH Institute for Astronomy taking a lead role, along with the Massachusetts Institute of Technology.

PS1 was installed on Haleakala where it will have the maximum view of the night sky. According to Maberry, Haleakala is an ideal viewing site for Pan-STARRS because of the clean air and stable weather conditions at a high elevation.

"The very best telescopes need the very best sites," he said. "In other words, high above the dust and pollen, things that interfere with the telescope."

Haleakala is particularly favorable because the peak stays above the thermal inversion layer, the air mass rising 5,000 to 7,000 feet where dust, pollen and man-made pollutants tend to be held. At 10,000 feet, the Maui summit can provide clean and clear skies for viewing.

In the preparations for the installation of PS1 - although it used an existing facility - IfA consulted with a Native Hawaiian kupuna and cultural specialist.

"Workers who work at the observatories must receive 'sense of place' training so that they understand that they are in a sense working in a church," Maberry said.

A full archaeological, biological and geological survey of the site was prepared, he said.

"We have identified areas that are considered either for-sure archeological sites or potential archeological sites, and we will protect those sites as required by rules and regulation."

Funding for Pan-STARRS is from the Air Force Research Laboratories, which also support the Air Force Maui Optical Station (AMOS) on the summit. Over the past five years, the program has spent close to $10 million a year on developing the telescope as well as on software research and development.

Since the Air Force funds only for research, development and construction, a consortium of scientific institutions organized to fund the operation of PS1. The PS1 Science Consortium includes Johns Hopkins University and Durham University, each providing $10 million and in return having access to the data gathered by the telescope.

"The deal with them is that they get to enjoy the use of that (PS1) for three and a half years ," Kaiser said, "and at the end of that time, we hope to have the other telescopes completed and the plan is to have PS1 join PS2, PS3 and PS4 on Mauna Kea in a single observatory."

PS1 is in its final stages of commissioning, which means that the telescope is working, but needs to be finely calibrated to assure that camera and telescope are in alignment before it's ready for night sky surveying.

"What we're doing is we're making very fine adjustments to the mirrors and the telescope and the lens to tune it up," said Kaiser.

IfA hopes that by the end of the year, the calibrations will be completed and the survey of the night sky can begin.

"Hopefully the telescope will be scanning the sky, generating huge amounts of data and each morning we'll be able to come to work and find out what it discovered last night," Kaiser said.

* Steven Tonthat was a summer intern with The Maui News. He has returned to classes for the fall semester at the University of Hawaii at Manoa.