An international team of scientists has discovered a wave or oscillation in Saturn’s atmosphere. For over 20 years, NASA scientists have been studying temperature changes in the upper atmosphere of Saturn using data from several telescopes on Mauna Kea and, more recently, up-close information from the Cassini spacecraft. The findings show temperature fluctuations rippling back and forth like a wave above and below Saturn’s equator. The Subaru Telescope played an important role in the project, and two Subaru astronomers contributed to the team’s success. The study shows a common link to similar phenomena on Earth and Jupiter, and further research hopes to determine why Saturn’s atmospheric temperature changes with the seasons.
Small Distant Galaxies Confirm Galaxy Formation Theories
April 7 , 2008
Small Distant Galaxies Confirm Galaxy Formation Theories
A team of international astronomers from Ehime University, Tohoku
University, and the California Institute of Technology studied a group
of newborn galaxies 12.5 billion light years away. The scientists
discovered 80 small galaxies using the Subaru Telscope, and conducted
follow-up observations with the Advanced Camera for Surveys on the
Hubble Space Telescope. As result, they have discovered that 17 out of 80 galaxies have only the size of 4000 light years. This was the first time the HST had completed
a systematic study of the detailed shapes of newborn galaxies. The
results identified galaxies 10 to 30 times smaller than current known
galaxies. This will reaffirm the theory that small newborn galaxies have
combined repeatedly to become larger galaxies over the past 10 billion
years. The observations show scenes of galactic formation anticipated
through theoretical studies.
(Japanese only)
Supernova Study Reveals Hidden Wonders and New Understandings
April 7 , 2008
Supernova Study Reveals Hidden Wonders and New Understandings
A collaborative team of researchers from the University of Tokyo,
Hokkaido University, and Hiroshima University carried out
multi-wavelength observations of supernova (SN) 2006jc using the Subaru
Telescope's Faint Object Camera And Spectrograph (FOCAS), the MAGNUM
Telescope and KANATA Telescope, as well as the infrared astronomical
satellite AKARI. The optical observations with the Subaru Telescope
were conducted over a 6-month period and revealed
sudden fading of SN 2006jc only 2 months after the explosion.
Together with the AKARI infrared observations, the team pinpointed
the site of dust formation in the supernova ejecta. Furthermore, a comparison
between theoretical calculations and physical observations illustrated
a scenario under which a massive star with more than 40 solar masses
undergoes extensive mass loss during its life that ultimately ends with
a supernova explosion.
(Japanese only)
Dozens of Gravitationally Lensed Galaxies Discovered in Distant Universe
February 20 , 2008
Dozens of Gravitationally Lensed Galaxies Discovered in Distant Universe
International astronomers on the COSMOS project announced a large
catalogue of strong gravitational lenses in the distant Universe.
Based on the observations with Hubble Space Telescope and several
ground-based telescopes including the Subaru Telescope, a staggering
67 new gravitational lensed galaxies were identified around massive
elliptical and lenticular galaxies. This sample demonstrates the
rich diversity of strong gravitational lenses, and, if this sample
rate has statistical significance, there would be nearly half a
million similar gravitational lenses in total over the whole sky.
Once more lenses are found, a census of galaxy masses in the Universe
can be created.
A Lightweight Disk Around a Lightweight Star May Harbor Earth-like Planet
February 8 , 2008
A Lightweight Disk Around a Lightweight Star May Harbor Earth-like Planet
A team of Japanese astronomers resolved a circumstellar disk around the young lightweight star FN Tau. The diminutive star is located in a star-forming region toward the Constellation Taurus at a distance 460 light years from Earth. This research group used the Coronagraphic Imager with Adaptive Optics (CIAO) at the Subaru Telescope to directly image FN Tau and the lightweight disk of planet-forming material surrounding it. This star is merely 100 thousand years old and weighs only one tenth of the Sun.
Supernovae are Not Spherical (or round) - Subaru Dissects the Interior of
Exploding Stars
January 31 , 2008
Supernovae are Not Spherical (or round) - Subaru Dissects the Interior of Exploding Stars
A research team of astronomers from Tokyo University, Hiroshima University and so on, observed 15 supernovae at 200 or more days after the explosion, using FOCAS at Subaru Telescope. Contrary to the
traditional view as spherically symmetric expansion, they revealed
that supernovae are commonly asymmetric. The final stage of a massive
star's life and the supernova explosion mechanism are still big
mysteries. This study boosts the research of not only the
supernovae but also another mysterious object - Gamma Ray Bursts.