Japan Searches Beyond Our Solar System . . .
Looking for New Worlds in Deep Space
Japan's Akari Infrared Observatory in Space
Satellites Rockets Surveying the Moon Exploring Planets
Japan's huge new Subaru Telescope is the world's largest telescope using a single mirror. The optical infra-red telescope, with its enormous, delicate 8.3-meter mirror, is positioned at the 13,796 ft. summit of the giant volcano Mauna Kea in Hawaii. The Subaru saw its "First Light" on January 28, 1999.
Operated by the National Astronomical Observatory of Japan (NAOJ), the $350-million Subaru Telescope can peer farther out than ever before from Earth's surface into some of the darkest corners of the universe.
Subaru is the Japanese word for the Pleiades star system, known to astronomers as the Seven Sisters.
Not only is Sabaru the world's largest infra-red telescope, it has the world's largest one-piece reflective mirror. It is a huge 26.9 ft. (8.2 meters) in diameter, yet only 7.9 inches (20 cm) thick, the mirror has more or less the same proportions as a contact lens.
Of course, images can be distorted by a mirror of that size so the Subaru is mounted on a computer-controlled support that has 261 small motors with screens and sensors -- actuators -- that push and pull the mirror to the right shape as needed. That lets the telescope detect clearly faint objects in remote areas of the Universe.
The telescope building is cylindrical, rather thana dome, so it can resist the wind. The mirror is adjusted by two parallel computers 100 times a second to counteract atmospheric turbulence, which would create twinkling stars.
On the volcano. The Subaru's precision mirror was polished for three years at the Corning Glass Works in New York state. It was trucked to Pittsburgh, loaded on a barge and floated down the Ohio River to the Mississippi, then down river to New Orleans. The mirror crossed the Gulf of Mexico on a larger ship, went through the Panama Canal, and crossed the Pacific to Hawaii where it was placed on a trailer hauled up the side of Mauna Kea. The journey lasted six weeks.
The mirror arrived at the observatory in November 1998, joining an elite group of international observatories atop Mauna Kea, including Keck 1 and Keck 2, listed in the 1998 Guinness Book of World Records as the world's largest. Their primary mirrors are composed of 36 segments and total 10 meters (32.8 feet) in diameter.
Mauna Kea is enjoyed by astronomers because it offers 325 nights a year of perfectly clear star-gazing and possibly the cleanest air on Earth. It is a one-hour drive up from Hilo, the nearest city, from tropical climate to snow-capped peak. At the top of the mountain is a clutch of observatories manned by astronomers from the United States, Britain, France, Canada, the Netherlands and Japan.
First Light. Astronomers refer to the first use of a telescope -- the first time light is reflected in its mirror -- as First Light.
The Sabaru's first actual observations began on Jan. 4, 1999. They created a number of spectacular images including photos of the planets Saturn and Jupiter, the Orion Nebula, the Trapezium, Orion's KL Region, star clouds in the Andromeda galaxy, a Seyfert 1 spiral galaxy known as NGC 4051, the Hickson Compact Group 40 galaxies near each other, the Abell 851 galaxy some five billion lightyears from Earth, and the most-distant known quasar, labeled SDSS J033829.31+002156.3, some 14 billion lightyears away.
Some First Light Photos by Japan's Sabaru Telescope:
Japan's Akari Infrared Telescope in Space:
Japan's Astro-F infrared astronomy observatory was launched February 21, 2006, on a three-stage solid-fuel M-5 rocket from the Uchinoura Space Center near Kagoshima on the southern tip of Kyushu Island.
JAXA artist's concept of Japan's Akari, formerly known as Astro-F, infrared astronomy observatory in space.
In orbit, the satellite was renamed Akari, which means light.
Akari will spend 18 months using its 27-inch aperture telescope to conduct an all-sky survey of energy received at infrared wavelengths.
The satellite's working lifetime is controlled by the amount of liquid helium it has stored on board. Some 45 gallons are necessary to chill the telescope and science instruments to six degrees Kelvin. That's -450° Fahrenheit, near absolute zero. The helium should last about 550 days.
The super-cold temperature increases the sensitivity of the instruments. After the liquid helium is exhausted, mechanical coolers will allow some observations to continue for five years.
Peering through dust. The new satellite will detect infrared light arriving at Earth from as many as 10 million objects scattered across the Universe.
Akari will look through thick clouds of cosmic dust that hide newborn stars from visible-light telescopes down on Earth. It also will study:Akari will extend the work completed some two decades earlier by the old Infrared Astronomical Satellite (IRAS). The IRAS infrared observatory was a project of the United States, United Kingdom and the Netherlands.
- brown dwarf stars not big enough to begin fusion and become a full-fledged star.
- active star-forming galaxies. Up to 10 million may be in range.
- extra-solar planetary systems, disks of dust around stars within 1,000 lightyears of Earth.
- previously undetected comets, maybe as many as 50.
IRAS conducted the first comprehensive infrared survey. Akari will improve upon the IRAS sky map by one order of magnitude.
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