Researchers plan to install the first Japanese radio telescope in Antarctica to study how stars are formed, enhancing the frozen continent’s reputation as the best location on Earth to observe cosmic phenomena.
The scientists from the University of Tsukuba and other institutions plan to transport the telescope on observation vessel Shirase to Syowa Station in Antarctica as early as in November.
It will then be hauled on a sled to its installation site 1,000 kilometers inland from Syowa Station.
Space observations are expected to start next fiscal year.
“We will be going all out toward elucidating the mechanism of star formation” Nario Kuno, an astronomy professor at the University of Tsukuba, said about the project.
Stars are created through gravitational pull in huge clouds of gases and dust particles.
The Japanese team said it intends to use the telescope to study the density and distribution of such gases by catching radio waves emitted by carbon monoxide.
“We will be examining the distribution of high-density gas in the galaxy,” Kuno said.
BATTLING THE ELEMENTS
Scientists from a range of countries carry out astronomical studies in Antarctica, taking advantage of its long stretches of clear, sunny days. In addition, water vapor that can block radio waves from space is relatively low in Antarctica.
The compact Japanese radio telescope is 30 centimeters in diameter. It will be set up near Dome Fuji Station at an altitude of 3,800 meters.
Observations will be conducted during the warmest times of the year, since temperatures there can drop to minus 40 degrees, even in summer.
Specialized countermeasures are planned to prevent the frigid cold from breaking the motor in the telescope, including using a heater, insulating the device and adopting low-temperature-resistant material for cables.
The National Institute of Polar Research and the Japan Meteorological Agency’s Meteorological Research Institute have conducted low-temperature tests on the telescope.
The Japanese team plans to dispatch research members for observation for six to seven weeks each summer. It is also looking to build a new observation base around the site for a larger 12-meter telescope.
The program to install the radio telescope in Antarctica started in 2004, but it was initially hampered by financial difficulties.
“Our priority is first and foremost ensuring that observations are done successfully, given concerns about whether we will be able to receive radio waves on site as instructed,” Kuno said.
PERFECT OBSERVATION SITE
The level of radio wave-blocking water vapor in Antarctica is estimated to be about one-tenth that in Hawaii, where many observation facilities, including the Subaru Telescope of the National Astronomical Observatory of Japan, are located.
Another stargazing advantage of Antarctica is its frequent days of high atmospheric transmissivity, which allows radio waves to more readily pass through the air.
Tohoku University in 2013, citing its atmospheric fluctuation survey in Antarctica, said high-altitude Dome Fuji Station is the “most ideal place on Earth for astronomical observation.”
“The type of radio wave monitoring we have in mind is only possible in Antarctica,” Kuno said. “Despite the challenging environment, we are confident that intriguing research results will emerge from observations there.”
The United States, China and Europe already have telescopes in Antarctica.
The South Pole Telescope (SPT), an observation base at the South Pole operated mainly by North American universities, started its observational mission in 2007.
The SPT, along with the Alma Observatory in Chile and a telescope in Hawaii, were used for imaging a black hole. The first such image of a black hole was released in 2019 by an international research team that included the National Astronomical Observatory of Japan.
China, which has raised its presence as a major space developer, has installed optical and radio telescopes measuring several tens of centimeters in diameter in Antarctica. The country plans to introduce a 60-cm telescope as part of its expanded research efforts.
NEUTRINO OBSERVATION
Antarctica is also home to a study center for neutrinos, an elementary particle that has been studied at Japan’s Kamiokande and Super-Kamiokande facilities.
IceCube in Antarctica, the world’s largest neutrino observatory, features 5,000 detectors embedded in a vertical shaft drilled 1.5 km to 2.5 km deep into the ice sheet. Its scale is equivalent to 800 Tokyo Domes.
Construction of IceCube began in 2004, and observations started in 2011.
Chiba University is one of the participating institutions involved in monitoring at IceCube.
Scientists from the university established a reliable method to capture any type of high-energy neutrino. In 2012, they were the first in the world to discover an ultra-high-energy neutrino.
In July this year, researchers from Chiba University and elsewhere released their findings based on 13 years of observational data from IceCube.
Their conclusion was that the main component of ultra-high-energy cosmic rays from outer space is not protons, as conventionally thought, but much heavier atomic nuclei.
IceCube is currently undergoing an upgrade, while plans are in place for a next-generation IceCube-Gen2 facility.
IceCube-Gen2 is expected to enter the construction phase around 2028 and have a sensitivity that is sevenfold or eightfold of that at IceCube.
IceCube’s upgrade entails implanting 700 high-performance detectors around existing ones, making their distribution denser.
IceCube has focused primarily on neutrino observations in the high-energy range. But the new arrangement should bolster neutrino observation performance in the low-energy band.
A building rehearsal was conducted in summer in the United States, and the upgrade is projected to be completed next year.
Shigeru Yoshida, an astronomy professor at Chiba University, which is responsible for developing the new detectors, expressed high expectations.
“We will be exploring neutrino astronomy even in the low-energy band,” he said. “Our specific hope is to identify celestial objects and capture the moment of a black hole’s birth while simultaneously leveraging probes in X-rays and visible light.”
AloJapan.com