Low-Frequency Observations of the Moon with the Murchison Widefield Array
A new generation of low-frequency radio telescopes is seeking to observe the redshifted 21 cm signal from the epoch of reionization (EoR), requiring innovative methods of calibration and imaging to overcome the difficulties of wide-field low-frequency radio interferometry. Precise calibration will b...
| Main Authors: | , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , |
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| Format: | Journal Article |
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IOP
2013
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| Subjects: | |
| Online Access: | http://hdl.handle.net/20.500.11937/18929 |
| _version_ | 1848749888203915264 |
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| author | McKinley, B. Briggs, Frank Kaplan, D. Greenhill, L. Bernardi, G. Bowman, Judd de Oliveira-Costa, A. Tingay, Steven Gaensler, B. Oberoi, Divya Johnston-Hollitt, M. Arcus, Wayne Barnes, D. Bunton, John Cappallo, Roger Corey, Brian Deshpande, Avinash DeSouza, Ludi Emrich, D. Goeke, Robert Hazelton, Bryna Herne, David Hewitt, Jacqueline Kasper, Justin Kincaid, Barton Koenig, R. Kratzenberg, Eric Lonsdale, Colin McWhirter, S. Mitchell, D. Morales, Miguel Morgan, Edward Ord, Stephen Pathikulangara, Joseph Prabu, T. Remillard, Ron Rogers, Alan Roshi, Anish Salah, J. Sault, Robert Shankar, N Udaya Srivani, K. Stevens, J. Subrahmanyan, R. Wayth, R. Waterson, Mark Webster, Rachel Whitney, Alan Williams, A. Williams, C. Wyithe, J. |
| author_facet | McKinley, B. Briggs, Frank Kaplan, D. Greenhill, L. Bernardi, G. Bowman, Judd de Oliveira-Costa, A. Tingay, Steven Gaensler, B. Oberoi, Divya Johnston-Hollitt, M. Arcus, Wayne Barnes, D. Bunton, John Cappallo, Roger Corey, Brian Deshpande, Avinash DeSouza, Ludi Emrich, D. Goeke, Robert Hazelton, Bryna Herne, David Hewitt, Jacqueline Kasper, Justin Kincaid, Barton Koenig, R. Kratzenberg, Eric Lonsdale, Colin McWhirter, S. Mitchell, D. Morales, Miguel Morgan, Edward Ord, Stephen Pathikulangara, Joseph Prabu, T. Remillard, Ron Rogers, Alan Roshi, Anish Salah, J. Sault, Robert Shankar, N Udaya Srivani, K. Stevens, J. Subrahmanyan, R. Wayth, R. Waterson, Mark Webster, Rachel Whitney, Alan Williams, A. Williams, C. Wyithe, J. |
| author_sort | McKinley, B. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | A new generation of low-frequency radio telescopes is seeking to observe the redshifted 21 cm signal from the epoch of reionization (EoR), requiring innovative methods of calibration and imaging to overcome the difficulties of wide-field low-frequency radio interferometry. Precise calibration will be required to separate the expected small EoR signal from the strong foreground emission at the frequencies of interest between 80 and 300 MHz. The Moon may be useful as a calibration source for detection of the EoR signature, as it should have a smooth and predictable thermal spectrum across the frequency band of interest. Initial observations of the Moon with the Murchison Widefield Array 32 tile prototype show that the Moon does exhibit a similar trend to that expected for a cool thermally emitting body in the observed frequency range, but that the spectrum is corrupted by reflected radio emission from Earth. In particular, there is an abrupt increase in the observed flux density of the Moon within the internationally recognized frequency modulated (FM) radio band. The observations have implications for future low-frequency surveys and EoR detection experiments that will need to take this reflected emission from the Moon into account. The results also allow us to estimate the equivalent isotropic power emitted by the Earth in the FM band and to determine how bright the Earth might appear at meter wavelengths to an observer beyond our own solar system. |
| first_indexed | 2025-11-14T07:28:05Z |
| format | Journal Article |
| id | curtin-20.500.11937-18929 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T07:28:05Z |
| publishDate | 2013 |
| publisher | IOP |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-189292017-09-13T16:00:10Z Low-Frequency Observations of the Moon with the Murchison Widefield Array McKinley, B. Briggs, Frank Kaplan, D. Greenhill, L. Bernardi, G. Bowman, Judd de Oliveira-Costa, A. Tingay, Steven Gaensler, B. Oberoi, Divya Johnston-Hollitt, M. Arcus, Wayne Barnes, D. Bunton, John Cappallo, Roger Corey, Brian Deshpande, Avinash DeSouza, Ludi Emrich, D. Goeke, Robert Hazelton, Bryna Herne, David Hewitt, Jacqueline Kasper, Justin Kincaid, Barton Koenig, R. Kratzenberg, Eric Lonsdale, Colin McWhirter, S. Mitchell, D. Morales, Miguel Morgan, Edward Ord, Stephen Pathikulangara, Joseph Prabu, T. Remillard, Ron Rogers, Alan Roshi, Anish Salah, J. Sault, Robert Shankar, N Udaya Srivani, K. Stevens, J. Subrahmanyan, R. Wayth, R. Waterson, Mark Webster, Rachel Whitney, Alan Williams, A. Williams, C. Wyithe, J. first stars Interferometric Moon reionization techniques extraterrestrial intelligence dark ages A new generation of low-frequency radio telescopes is seeking to observe the redshifted 21 cm signal from the epoch of reionization (EoR), requiring innovative methods of calibration and imaging to overcome the difficulties of wide-field low-frequency radio interferometry. Precise calibration will be required to separate the expected small EoR signal from the strong foreground emission at the frequencies of interest between 80 and 300 MHz. The Moon may be useful as a calibration source for detection of the EoR signature, as it should have a smooth and predictable thermal spectrum across the frequency band of interest. Initial observations of the Moon with the Murchison Widefield Array 32 tile prototype show that the Moon does exhibit a similar trend to that expected for a cool thermally emitting body in the observed frequency range, but that the spectrum is corrupted by reflected radio emission from Earth. In particular, there is an abrupt increase in the observed flux density of the Moon within the internationally recognized frequency modulated (FM) radio band. The observations have implications for future low-frequency surveys and EoR detection experiments that will need to take this reflected emission from the Moon into account. The results also allow us to estimate the equivalent isotropic power emitted by the Earth in the FM band and to determine how bright the Earth might appear at meter wavelengths to an observer beyond our own solar system. 2013 Journal Article http://hdl.handle.net/20.500.11937/18929 10.1088/0004-6256/145/1/23 IOP fulltext |
| spellingShingle | first stars Interferometric Moon reionization techniques extraterrestrial intelligence dark ages McKinley, B. Briggs, Frank Kaplan, D. Greenhill, L. Bernardi, G. Bowman, Judd de Oliveira-Costa, A. Tingay, Steven Gaensler, B. Oberoi, Divya Johnston-Hollitt, M. Arcus, Wayne Barnes, D. Bunton, John Cappallo, Roger Corey, Brian Deshpande, Avinash DeSouza, Ludi Emrich, D. Goeke, Robert Hazelton, Bryna Herne, David Hewitt, Jacqueline Kasper, Justin Kincaid, Barton Koenig, R. Kratzenberg, Eric Lonsdale, Colin McWhirter, S. Mitchell, D. Morales, Miguel Morgan, Edward Ord, Stephen Pathikulangara, Joseph Prabu, T. Remillard, Ron Rogers, Alan Roshi, Anish Salah, J. Sault, Robert Shankar, N Udaya Srivani, K. Stevens, J. Subrahmanyan, R. Wayth, R. Waterson, Mark Webster, Rachel Whitney, Alan Williams, A. Williams, C. Wyithe, J. Low-Frequency Observations of the Moon with the Murchison Widefield Array |
| title | Low-Frequency Observations of the Moon with the Murchison Widefield Array |
| title_full | Low-Frequency Observations of the Moon with the Murchison Widefield Array |
| title_fullStr | Low-Frequency Observations of the Moon with the Murchison Widefield Array |
| title_full_unstemmed | Low-Frequency Observations of the Moon with the Murchison Widefield Array |
| title_short | Low-Frequency Observations of the Moon with the Murchison Widefield Array |
| title_sort | low-frequency observations of the moon with the murchison widefield array |
| topic | first stars Interferometric Moon reionization techniques extraterrestrial intelligence dark ages |
| url | http://hdl.handle.net/20.500.11937/18929 |