June 9th, 2007
“Boring” light from red dwarf star Gliese 581 means better odds for extraterrestrial life in that planetary system, according to University of British Columbia astronomer Jaymie Matthews.
Read the full text here:
"Boring Star May Mean Livelier Planet: UBC Astronomer"
June 30th, 2007
MOST celebrates its fourth birthday today, a day before Canada celebrates
the nation’s birthday. And to mark the occasion, the Canadian Space Agency
and the MOST Science Team are giving Canadian students, amateur astronomers
and stargazing enthusiasts the chance to make their own discoveries with
this tiny but powerful space observatory.
The MOST (Microvariability & Oscillations of STars) satellite was launched
four years ago today from a Russian cosmodrome, aboard a former Soviet
nuclear missile. It was intended to be a one-year mission, but has
exceeded every expectation of mission planners since blasting into space.
The science MOST has accomplished sometimes sounds more than astromedicine
than astrophysics: performing “ultrasound” on stellar embryos, diagnosing
the skin complexion and hyperactivity of a pre-teen sun, and taking the
pulses of stellar senior citizens. MOST has also begun the search for Terra
Nova – looking for Earths around other stars - and the study of weather on
planets beyond the Solar System (see also
UBC Media Release).
While the exoplanetary science and many other discoveries by MOST were never
part of the original mission plan, the Canadian Space Agency and the MOST
Team had planned from the start to give ordinary Canadians a chance to
observe with their space telescope, 820 km above the Earth. “MOST was
nicknamed the “Humble Space Telescope” before launch. It has since become
“The Little Telescope That Could”. Now MOST can also stand for “My Own Space
Telescope”, announced Dr. Matthews today. “You don’t have to be a rocket
scientist to wonder about the universe, and Canada’s students and amateur
astronomers have ‘the right stuff’ to explore those cosmic wonders.”
All Canadians will have the chance to submit proposals for scientific
observations with MOST. The MOST Science Team will select one or more of
the best proposals that are feasible with the satellite. MOST will then
collect the observations and the Team will work with the winners to analyse
and publish the results.
Information on MOST capabilities, a target selection tool,
and on-line proposal submission form can be found at
"MOST = My Own Space Telescope - Canadians' opportunity to propose MOST science".
So start thinking of the science you might be able to do with Canada's space telescope.
August 10th, 2007
Sometimes two stars can be better than one. MOST was
intended to study single stars, but it has discovered previously
unrecognised eclipsing binaries, and monitored a binary containing a
white dwarf and an active red dwarf star.
August 15th, 2007
Among the MOST guide stars used for spacecraft pointing in June 2006,
we found a binary star consisting of two hot massive B-type stars with
an orbital period of only 2.27 days. This system, HD 313926, stood out
because it has the highest orbital eccentricity among such short-period
B-type binaries. The fact that the orbit of HD 313926 has not yet become
circular suggests that the system is very young, even compared to other
young B stars. The analysis, led by MOST Science Team member Dr. Slavek
Rucinski (Director of the David Dunlap Observatory), will appear in the
Monthly Notices of the Royal Astronomical Society.
In the Hyades star cluster (visible to the eye in the constellation
Taurus) is a binary system, V471 Tau, containing a K2 dwarf and a white
dwarf. Only ten days of MOST monitoring revealed seven flares of the red
dwarf whose energies were among the highest ever observed in that star,
despite the fact that the MOST photometry indicated less surface spots
than seen in the past. If this star undergoes seven powerful flares in
a week and a half when near a minimum in its activity cycle, we wouldn't
want to be close to it during maximum activity! Partly simultaneous
optical spectroscopy from the David Dunlap Observatory (DDO) indicate
that activity is less concentrated on the surface of the red dwarf
directly beneath the white dwarf, whose proximity is believed to be a
major factor in raising activity on its companion. These results will
appear in The Astronomical Journal next month, in a paper with lead
authors Krzysztof Z. Kaminski (Astronomical Observatory, Adam Mickiewicz
University, Poznan, Poland) and MOST Science Team member Slavek Rucinski.
Both papers can be downloaded from the MOST Science Page and the data
will be available soon in the MOST Public Data Archive, accessible via the Science
Image (above right):
The Hyades star cluster. Image credit:
Palomar Sky Survey
Procyon and eta Bootis revisited. MOST reobserved these
two stars in 2005, to extend the original investigations of acoustic
oscillations (or lack thereof) in these somewhat evolved solar-type stars.
New data reduction and analysis techniques were developed to better
identify and correct for background variations due to scattered Earthshine
in the MOST photometry. These were applied to the 2005 data, and used to
reexamine the 2004 light curves. The results reaffirm the null detection
of oscillation modes in the 2004 MOST photometry of Procyon, puzzling due
to the fact they were reported in groundbased spectroscopy. The evidence
for such oscillations in eta Bootis persists, but the Procyon null
detections, and the comparison of 2004 and 2005 eta Boo results, indicate
that pulsation modes are probably short-lived in both stars. This work,
led by MOST Science Team member David Guenther (St. Mary's University,
Institute for Computational Astrophysics) and with major contributions by
University of Vienna doctoral student Thomas Kallinger, will appear in the
journal Communications in Asteroseismology. An electronic version of the
paper can be downloaded from the MOST Science page, and the data are now
in the MOST Public Data Archive, accessed via the Science page.
Coming attraction: In January/February of this year, Procyon was
reobserved yet again by MOST and we obtained the best photometry ever
achieved in the four years of the satellite's science operations. These
results will be appearing soon.