SPITZER SECONDARY ECLIPSES OF WASP-18b

Journal Article · Sun Nov 20 04:00:00 EST 2011 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/742/1/35; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA)· OSTI ID:21612608

Nymeyer, Sarah; Harrington, Joseph; Hardy, Ryan A; Stevenson, Kevin B; Campo, Christopher J; Blecic, Jasmina; Bowman, William C; Britt, Christopher B. T.; Cubillos, Patricio ^[1]; Madhusudhan, Nikku ^[2]; Collier-Cameron, Andrew; Maxted, Pierre F. L. ^[3]; Loredo, Thomas J ^[4]; Hellier, Coel; Anderson, David R ^[5]; Gillon, Michael ^[6]; Hebb, Leslie ^[7]; Wheatley, Peter J ^[8]; Pollacco, Don ^[9]

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1. Planetary Sciences Group, Department of Physics, University of Central Florida, Orlando, FL 32816-2385 (United States)
2. Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States)
3. School of Physics and Astronomy, University of St. Andrews, North Haugh, Fife KY16 9SS (United Kingdom)
4. Center for Radiophysics and Space Research, Space Sciences Building, Cornell University, Ithaca, NY 14853-6801 (United States)
5. Astrophysics Group, Keele University, Staffordshire ST5 5BG (United Kingdom)
6. Institut d'Astrophysique et de Geophysique, Universite de Liege, Allee du 6 Aout 17, Bat. B5C, 4000 Liege (Belgium)
7. Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37235 (United States)
8. Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom)
9. Astrophysics Research Centre, School of Mathematics and Physics, Queen's University, University Road, Belfast BT7 1NN (United Kingdom)

The transiting exoplanet WASP-18b was discovered in 2008 by the Wide Angle Search for Planets project. The Spitzer Exoplanet Target of Opportunity Program observed secondary eclipses of WASP-18b using Spitzer's Infrared Array Camera in the 3.6 {mu}m and 5.8 {mu}m bands on 2008 December 20, and in the 4.5 {mu}m and 8.0 {mu}m bands on 2008 December 24. We report eclipse depths of 0.30% {+-} 0.02%, 0.39% {+-} 0.02%, 0.37% {+-} 0.03%, 0.41% {+-} 0.02%, and brightness temperatures of 3100 {+-} 90, 3310 {+-} 130, 3080 {+-} 140, and 3120 {+-} 110 K in order of increasing wavelength. WASP-18b is one of the hottest planets yet discovered-as hot as an M-class star. The planet's pressure-temperature profile most likely features a thermal inversion. The observations also require WASP-18b to have near-zero albedo and almost no redistribution of energy from the day side to the night side of the planet.

• OSTI ID: 21612608
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 742; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ALBEDO
ATMOSPHERES
BRIGHTNESS
CAMERAS
ECLIPSE
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
PLANETS
SATELLITE ATMOSPHERES
STARS
TEMPERATURE INVERSIONS
WAVELENGTHS