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The Microlensing Observations in Astrophysics (MOA) telescope dome at the top of Mount John
Microlensing Observations in Astrophysics (MOA ) is a collaborative project between researchers in
New Zealand
[1] and
Japan ,
[2] led by Professor Yasushi Muraki of
Nagoya University .
[3] They use
microlensing to observe
dark matter ,
extra-solar planets , and
stellar atmospheres from the
Southern Hemisphere . The group concentrates especially on the detection and observation of
gravitational microlensing events of high magnification, of order 100 or more, as these provide the greatest sensitivity to extrasolar planets. They work with other groups in
Australia , the
United States and elsewhere. Observations are conducted at New Zealand's
Mt. John University Observatory using a 1.8 m (70.9 in)
reflector telescope built for the project.
[4]
In September 2020, astronomers using
microlensing techniques reported the detection, for the first time, of an
earth-mass
rogue planet unbounded by any star, and free floating in the
Milky Way galaxy .
[5]
[6] In January 2022 in collaboration with
Optical Gravitational Lensing Experiment (OGLE) they reported in a preprint the first
rogue BH
[7]
[8]
[9]
[10] while there have been others candidates
[11] this is the most solid detection so far as their technique allowed to measure not only the amplification of light but also its deflection by the BH from the microlensing data.
MOA telescope mirror images
Underside of main mirror
Camera assembly
Main mirror, side view
Planets discovered
The following planets have been announced by this survey, some in conjunction with other surveys.
See also
References
^ Staff (1995).
"MOA (Microlensing observtion in Astrophysics)" (PDF) .
Caltech . Retrieved 3 October 2020 .
^ Yock, Philip (2012). "Review article - A quarter century of astrophysics with Japan".
New Zealand Science Review . 69 (3).
arXiv :
1510.05688 .
^ Latham, David W.; Gaudi, B. Scott (2014). "Microlensing Observations in Astrophysics".
Encyclopedia of Astrobiology (PDF) . p. 1.
doi :
10.1007/978-3-642-27833-4_1850-2 .
ISBN
978-3-642-27833-4 . Retrieved 3 October 2020 .
^ Sumi, T.; et al. (1 July 2003).
"Microlensing Optical Depth toward the Galactic Bulge from Microlensing Observations in Astrophysics Group Observations during 2000 with Difference Image Analysis" .
The Astrophysical Journal . 591 (1): 204–227.
arXiv :
astro-ph/0207604 .
Bibcode :
2003ApJ...591..204S .
doi :
10.1086/375212 .
S2CID
118776894 . Retrieved 3 October 2020 .
^ Gough, Evan (1 October 2020).
"A Rogue Earth-Mass Planet Has Been Discovered Freely Floating in the Milky Way Without a Star" .
Universe Today . Retrieved 2 October 2020 .
^ Mroz, Przemek; et al. (29 September 2020).
"A terrestrial-mass rogue planet candidate detected in the shortest-timescale microlensing event" . The Astrophysical Journal . 903 (1): L11.
arXiv :
2009.12377 .
Bibcode :
2020ApJ...903L..11M .
doi :
10.3847/2041-8213/abbfad .
S2CID
221971000 .
^ Sahu, Kailash C.; Anderson, Jay; Casertano, Stefano; Bond, Howard E.; Udalski, Andrzej; Dominik, Martin; Calamida, Annalisa; Bellini, Andrea; Brown, Thomas M.; Rejkuba, Marina; Bajaj, Varun (25 May 2022).
"An Isolated Stellar-mass Black Hole Detected through Astrometric Microlensing" . The Astrophysical Journal . 933 : 83.
arXiv :
2201.13296 .
Bibcode :
2022ApJ...933...83S .
doi :
10.3847/1538-4357/ac739e .
S2CID
246430448 .
^ Lam, Casey Y.; Lu, Jessica R.; Udalski, Andrzej; Bond, Ian; Bennett, David P.; Skowron, Jan; Mroz, Przemek; Poleski, Radek; Sumi, Takahiro; Szymanski, Michal K.; Kozlowski, Szymon (31 May 2022).
"An Isolated Mass-gap Black Hole or Neutron Star Detected with Astrometric Microlensing" . The Astrophysical Journal Letters . 933 (1): L23.
arXiv :
2202.01903 .
Bibcode :
2022ApJ...933L..23L .
doi :
10.3847/2041-8213/ac7442 .
S2CID
246608178 .
^ Gianopoulos, Andrea (7 June 2022).
"Hubble Determines Mass of Isolated Black Hole Roaming Milky Way" . NASA . Retrieved 12 June 2022 .
^ O'Callaghan, Jonathan.
"Astronomers Find First Ever Rogue Black Hole Adrift in the Milky Way" . Scientific American . Retrieved 8 February 2022 .
^ Bennett, D. P.; Becker, A. C.; Quinn, J. L.; Tomaney, A. B.; Alcock, C.; Allsman, R. A.; Alves, D. R.; Axelrod, T. S.; Calitz, J. J.; Cook, K. H.; Drake, A. J. (10 November 2002).
"Gravitational Microlensing Events Due to Stellar‐Mass Black Holes" . The Astrophysical Journal . 579 (2): 639–659.
arXiv :
astro-ph/0109467 .
Bibcode :
2002ApJ...579..639B .
doi :
10.1086/342225 .
ISSN
0004-637X .
S2CID
44193135 .
External links
Forms of dark matter Hypothetical particles Theories and objects Search experiments
Direct detection Indirect detection Other projects
Potential
dark galaxies Related
Ground-based Space missions
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Related