BRITE-Toronto
   HOME

TheInfoList



OR:

BRITE-Constellation is an ongoing space mission carrying out two-band photometry in wide fields with a constellation of six (presently, three operational) BRIght Target Explorer (BRITE) nanosatellites. The mission was built by a consortium of three countries, Canada, Austria, and Poland, each operating two BRITE satellites. The six satellites were launched into low-Earth orbits between February 2013 and August 2014. Each satellite is a cube-shaped spacecraft with sides of hosting an optical telescope of aperture feeding an uncooled CCD with a field of view of approximately 20° × 24°. The satellites were intended for photometry of the brightest stars in single passband located in the blue (three satellites) or red (the other three satellites) part of the optical range.


Early history

The idea of using
microsatellite A microsatellite is a tract of repetitive DNA in which certain Sequence motif, DNA motifs (ranging in length from one to six or more base pairs) are repeated, typically 5–50 times. Microsatellites occur at thousands of locations within an organ ...
for scientific observations, especially for photometry of bright stars, was born during discussions on possible designs for Canada's first scientific satellite. Discussions led by Kieran Carroll and Slawek Rucinski (
University of Toronto The University of Toronto (UToronto or U of T) is a public university, public research university whose main campus is located on the grounds that surround Queen's Park (Toronto), Queen's Park in Toronto, Ontario, Canada. It was founded by ...
) led to three concepts, including a wide-field imager for photometric measurements. A design concept for an astronomical nano-satellite was developed in 2002 by the
Institute for Aerospace Studies An institute is an organizational body created for a certain purpose. They are often research organisations (research institutes) created to do research on specific topics, or can also be a professional body. In some countries, institutes ca ...
at the
University of Toronto The University of Toronto (UToronto or U of T) is a public university, public research university whose main campus is located on the grounds that surround Queen's Park (Toronto), Queen's Park in Toronto, Ontario, Canada. It was founded by ...
under the
Canadian Advanced Nanospace eXperiment Program The Canadian Advanced Nanospace eXperiment (CanX) program is a Canadian CubeSat nanosatellite program operated by the University of Toronto Institute for Aerospace Studies, Space Flight Laboratory (UTIAS/SFL). The program's objectives are to inv ...
as Can X-3 in cooperation with a team of Canadian astronomers, headed by Slavek Rucinski, as a first fully three-axis stabilized satellite of 20 cm × 20 cm × 20 cm size. In September 2004, a workshop on nano-satellites for astronomy was organized in Vienna in cooperation with the
Austrian Space Agency The Austrian Space Agency, officially known since 2005 as the Aeronautics and Space Agency (German: Agentur für Luft- und Raumfahrt), is an organization whose purpose is to coordinate Austrian space exploration-related activities. It has been in ...
(ASA, now Aeronautics and Space Agency of the FFG). A proposal from the Institute of Communication Networks and Satellite Communications of the
Graz University of Technology Graz University of Technology (, short TU Graz) is a public research university located in Styria, Austria. It was founded in 1811 by Archduke John of Austria and is the oldest science and technology research and educational institute in Austria. ...
, led by Otto Koudelka, for funding of BRITE-Austria (TUGSat-1) was accepted by ASA in 2006 and was built at TUG in cooperation with SFL. In March 2005 a program for improving the infrastructure of Austrian Universities was established by the Austrian Ministry of Science and Technology, to which the
University of Vienna The University of Vienna (, ) is a public university, public research university in Vienna, Austria. Founded by Rudolf IV, Duke of Austria, Duke Rudolph IV in 1365, it is the oldest university in the German-speaking world and among the largest ...
submitted a proposal for
UniBRITE UniBRITE-1 is, along with TUGSAT-1, one of the first two Austrian satellites to be launched. Along with TUGSAT, it operates as part of the BRIght Target Explorer constellation of satellites. The two spacecraft were launched aboard the same rocke ...
(PI: Werner W. Weiss), which was accepted in October 2005 and UniBRITE was ordered at SFL. Following an initiative by Slavek Rucinski, Aleksander Schwarzenberg-Czerny (
CAMK CAMK, also written as CaMK or CCaMK, is an abbreviation for the Ca2+/calmodulin-dependent protein kinase class of enzymes. CAMKs are activated by increases in the concentration of intracellular calcium ions (Ca2+) and calmodulin. When activated, ...
) was able to obtain funding for two Polish BRITE satellites at the end of 2009. Following that, the
Canadian Space Agency The Canadian Space Agency (CSA; ) is the national space agency of Canada, established in 1990 by the ''Canadian Space Agency Act''. The President of the Canadian Space Agency, president is Lisa Campbell (civil servant), Lisa Campbell, who took ...
(CSA) finally funded BRITE-Toronto and BRITE-Montréal (PI:
Anthony Moffat Anthony (Tony) F.J. Moffat is an emeritus professor of astronomy at the Université de Montréal in Montreal, Quebec, Canada. He was appointed as a fellow of the Royal Society of Canada in 2001. Moffat's research focuses on massive stars ( Wolf-R ...
,
University of Montréal A university () is an institution of tertiary education and research which awards academic degrees in several academic disciplines. ''University'' is derived from the Latin phrase , which roughly means "community of teachers and scholars". Univ ...
) in 2011. Hence, BRITE-Constellation was born as a collaboration between Austria, Canada and Poland.


Launches and the status of the mission

The six BRITE nanosatellites were lifted into low-Earth orbits in four independent launches carried out by three space agencies:
Indian Space Research Organisation The Indian Space Research Organisation (ISRO ) is India's national List of government space agencies, space agency, headquartered in Bengaluru, Karnataka. It serves as the principal research and development arm of the Department of Space (DoS), ...
(two Austrian satellites),
Roscosmos The State Corporation for Space Activities "Roscosmos", commonly known simply as Roscosmos (), is a State corporation (Russia), state corporation of the Russian Federation responsible for space science, space flights, List of space agencies, c ...
(two Canadian satellites and Polish BRITE-Lem), and
China National Space Administration The China National Space Administration (CNSA) is a government agency of the People's Republic of China headquartered in Haidian District, Haidian, Beijing, responsible for civil space administration and international space cooperation. These ...
(Polish BRITE-Heweliusz). Details of the launches are summarised in the table below. Canadian BRITE-Montréal failed to detach from the launcher for unknown reasons and was lost. The other five satellites successfully passed the commissioning phase and began regular observations. The nominal lifetime of the BRITE satellites was foreseen to be two years. Due to problems with the attitude control system (ACS), observations with UniBRITE were suspended in August 2019, more than six years after its launch. About a year later, in May 2020, BRITE-Lem started to suffer from similar problems and observations with this satellite, also after more than six years in orbit, were suspended. Currently, the three remaining satellites, BRITE-Austria, BRITE-Toronto and BRITE-Heweliusz, are still active. Regardless of their status, observations with the BRITE satellites, and thus the entire mission, are expected to be completed by the end of 2024.


Satellites

BRITE satellites are made up of the following subsystems: * The Attitude Control System (ACS), which consists of reaction wheels, magnetorquers, magnetometer, Sun sensors and star trackers. The system ensures that the satellites are stabilized with an accuracy of approximately 1'. * A telescope (refractor) with an aperture diameter of 3 cm. The refractor consists of 5 lenses with an effective focal length of 7 cm, providing a field of view of 24 degrees in diameter. To avoid saturation during exposures, the detectors are placed out of focus, making BRITE images intentionally defocused. An exception is BRITE-Heweliusz, whose optics consists of 4 lenses and its detector is placed on the opposite side of the focal plane than for the other satellites. This results in a slightly smaller field of view for this satellite. * Each BRITE satellite is equipped with one interference filter, either blue (BAb, BMb and BLb) or red (UBr, BTr and BHr). The blue filter transmits light in the range of 395-456 nm, the red filter, in the range of 549-693 nm, as shown in the figure. * The detectors on-board BRITE satellites are rectangular KAI-11002 4072 × 2720 pixels CCD chips. A small vignetting leads to an effective observed area of approximately 20° × 24°. The temperatures at which they operate on board the BRITE satellites range between 0 °C and 40 °C. The image scale in the detector plane amounts to 21 arcsec per pixel. * On-board computers for data storage, maintenance and operating the ACS. * Solar cells located on the sides of the satellite and a Li-ion battery to provide power for on-board systems when the satellite is in the Earth's shadow. * Communication antenna for transmission between satellite and ground stations, operating in S-band.


References


External links


BRITE-Constellation web pageBRITE-Constellation WikiCanadian Space Agency
{{Orbital launches in 2014 Student satellites Satellites of Canada