WASP-24b
Encyclopedia
WASP-24b is a Hot Jupiter
detected in the orbit of the F-type star WASP-24
. The planet is approximately the same size and mass of Jupiter, but it orbits at approximately 4% of the mean distance between the Earth and the Sun every two days. WASP-24b was observed by SuperWASP
starting in 2008; after two years of observations, follow-ups led to the collection of the information that led to the planet's discovery.
project, a ground-based consortium aiming to discover planets that transit (cross in front of) their host stars with respect to Earth. 9,750 data points were collected for the light curve; the star was flagged as host to possible transit events, prompting a team of astronomers from Europe and the United States to conduct follow-up observations.
The Fibre-Fed Echelle Spectrograph (FIES) on the Roque de los Muchachos Observatory
's Nordic Optical Telescope
provided radial velocity
measurements for the system; additional calibrations during the observational period also provided the spectrum of the star. Ten Doppler spectroscopy
observations were collected between December 31, 2008 and April 10, 2009. Follow-ups between January 29, 2009 and July 26, 2009 were conducted using the CORALIE spectrograph
on the Leonhard Euler Telescope
at La Silla Observatory
, broadening knowledge of the star's spectrum, and collecting additional radial velocity measurements. These observations revealed that a body of planetary mass was orbiting the star. Analysis of the data led to the rejection of other false positive scenarios, and later, to the confirmation of the planet WASP-24b.
Because of the star's position in the sky, WASP-24 was visible to both the Faulkes Telescope North
on Maui and the Faulkes Telescope South
in Australia. The telescopes were used to observe the star's light, thereby detecting times when WASP-24b might have transited its star. The Faulkes telescopes collected data on two complete transits and one partial one. During this period, a nearby eclipsing binary star called N1 was considered and avoided to avoid contaminating the collected light samples.
Information collected by the Faulkes telescopes was extrapolated to reveal the characteristics of the star, and from there of the planet. The planet's discoverers compared it to HD 189733 b
, which resembles WASP-24b in orbit length
, mass, and radius. The planet's discovery was first reported on the SuperWASP website.
s (1,076 light years) away. The star is an estimated 1.129 times the mass
of the Sun. WASP-24 is also 1.147 times the radius of the star, making the star both larger and more massive than the Sun. WASP-24 has an effective temperature
is 6075 K, hotter than the Sun. WASP-24 has a high metallicity
; with [Fe/H] = 0.07, WASP-24 has 1.17 times the amount of iron measured in the Sun. The star's estimated age is 1.6 billion years old, although the star's age is not well-constrained.
WASP-24 has an apparent magnitude
of 11.3. It cannot be seen from Earth with the naked eye
.
that has a mass of 1.032 times the mass
of Jupiter. Its radius is 1.104 times the radius of Jupiter. In addition, with a mean distance of 0.0359 AU
between it and its star, where one AU is the average distance between the Earth and the Sun, WASP-24b completes an orbit every 2.3412083 days (roughly 57 hours). In comparison, Mercury
orbits the Sun every 87.97 days at a distance of 0.387 AU.
WASP-24b's orbital inclination is 83.64º, placing WASP-24b almost edge-on with respect to Earth and to its host star.
Hot Jupiter
Hot Jupiters are a class of extrasolar planet whose mass is close to or exceeds that of Jupiter...
detected in the orbit of the F-type star WASP-24
WASP-24
WASP-24 is an F-type star with the Hot Jupiter planet WASP-24b in orbit. WASP-24 is slightly larger and more massive than the Sun, but is more metal-rich and hotter than the Sun. However, it is probably not a part of the main sequence, as seen in its young age...
. The planet is approximately the same size and mass of Jupiter, but it orbits at approximately 4% of the mean distance between the Earth and the Sun every two days. WASP-24b was observed by SuperWASP
SuperWASP
SuperWASP is an international academic organisation performing an ultra-wide angle search for transiting extrasolar planets with the aim of covering the entire sky down to ~15th magnitude.-Equipment:...
starting in 2008; after two years of observations, follow-ups led to the collection of the information that led to the planet's discovery.
Discoveries
Between March 5, 2008 and March 9, 2009, WASP-24 was under the observation of both the Northern and Southern branches of the SuperWASPSuperWASP
SuperWASP is an international academic organisation performing an ultra-wide angle search for transiting extrasolar planets with the aim of covering the entire sky down to ~15th magnitude.-Equipment:...
project, a ground-based consortium aiming to discover planets that transit (cross in front of) their host stars with respect to Earth. 9,750 data points were collected for the light curve; the star was flagged as host to possible transit events, prompting a team of astronomers from Europe and the United States to conduct follow-up observations.
The Fibre-Fed Echelle Spectrograph (FIES) on the Roque de los Muchachos Observatory
Roque de los Muchachos Observatory
Roque de los Muchachos Observatory is an astronomical observatory located in the municipality of Garafía on the island of La Palma in the Canary Islands...
's Nordic Optical Telescope
Nordic Optical Telescope
The Nordic Optical Telescope is an astronomical telescope located at Roque de los Muchachos Observatory, La Palma in the Canary Islands. First light came in 1988, with regular observing beginning in 1989. It is funded by Denmark, Sweden, Iceland, Norway and Finland...
provided radial velocity
Radial velocity
Radial velocity is the velocity of an object in the direction of the line of sight . In astronomy, radial velocity most commonly refers to the spectroscopic radial velocity...
measurements for the system; additional calibrations during the observational period also provided the spectrum of the star. Ten Doppler spectroscopy
Doppler spectroscopy
Doppler spectroscopy, also known as radial velocity measurement, is a spectroscopic method for finding extrasolar planets. It involves the observation of Doppler shifts in the spectrum of the star around which the planet orbits....
observations were collected between December 31, 2008 and April 10, 2009. Follow-ups between January 29, 2009 and July 26, 2009 were conducted using the CORALIE spectrograph
CORALIE spectrograph
The CORALIE spectrograph is an echelle type spectrograph used for astronomy. This instrument used with a telescope to measure star spectra for the Doppler effect to detect the presence of extrasolar planets by the radial velocity method...
on the Leonhard Euler Telescope
Leonhard Euler Telescope
Leonhard Euler Telescope, or Swiss 1.2-m Leonhard Euler Telescope, is a diameter aperture reflecting telescope at the Geneva Observatory at La Silla Observatory. It is use for astronomy, and runs the CORALIE echelle spectrograph to search for planets. Its first planet discovery was of one in orbit...
at La Silla Observatory
La Silla Observatory
La Silla Observatory is an astronomical observatory in Chile with three telescopes built and operated by the European Southern Observatory organisation, and several others are partly maintained by ESO...
, broadening knowledge of the star's spectrum, and collecting additional radial velocity measurements. These observations revealed that a body of planetary mass was orbiting the star. Analysis of the data led to the rejection of other false positive scenarios, and later, to the confirmation of the planet WASP-24b.
Because of the star's position in the sky, WASP-24 was visible to both the Faulkes Telescope North
Faulkes Telescope North
The Faulkes Telescope North is a clone of the Liverpool Telescope, and is located at Haleakala Observatory in the U.S. state of Hawaii.The telescope is owned and operated by LCOGT. This telescope and its sister telescope Faulkes Telescope South are used by research and education groups across the...
on Maui and the Faulkes Telescope South
Faulkes Telescope South
The Faulkes Telescope South is a clone of the Liverpool Telescope and is located at Siding Spring Observatory. It is a Ritchey-Chrétien telescope....
in Australia. The telescopes were used to observe the star's light, thereby detecting times when WASP-24b might have transited its star. The Faulkes telescopes collected data on two complete transits and one partial one. During this period, a nearby eclipsing binary star called N1 was considered and avoided to avoid contaminating the collected light samples.
Information collected by the Faulkes telescopes was extrapolated to reveal the characteristics of the star, and from there of the planet. The planet's discoverers compared it to HD 189733 b
HD 189733 b
HD 189733 b is an extrasolar planet approximately 63 light-years away in the constellation of Vulpecula . The planet was discovered orbiting the star HD 189733 on October 5, 2005, when astronomers in France observed the planet transiting across the face of the star. The planet is classified as a...
, which resembles WASP-24b in orbit length
Orbital period
The orbital period is the time taken for a given object to make one complete orbit about another object.When mentioned without further qualification in astronomy this refers to the sidereal period of an astronomical object, which is calculated with respect to the stars.There are several kinds of...
, mass, and radius. The planet's discovery was first reported on the SuperWASP website.
Host star
WASP-24 is a F-type star located 330 parsecParsec
The parsec is a unit of length used in astronomy. It is about 3.26 light-years, or just under 31 trillion kilometres ....
s (1,076 light years) away. The star is an estimated 1.129 times the mass
Solar mass
The solar mass , , is a standard unit of mass in astronomy, used to indicate the masses of other stars and galaxies...
of the Sun. WASP-24 is also 1.147 times the radius of the star, making the star both larger and more massive than the Sun. WASP-24 has an effective temperature
Effective temperature
The effective temperature of a body such as a star or planet is the temperature of a black body that would emit the same total amount of electromagnetic radiation...
is 6075 K, hotter than the Sun. WASP-24 has a high metallicity
Metallicity
In astronomy and physical cosmology, the metallicity of an object is the proportion of its matter made up of chemical elements other than hydrogen and helium...
; with [Fe/H] = 0.07, WASP-24 has 1.17 times the amount of iron measured in the Sun. The star's estimated age is 1.6 billion years old, although the star's age is not well-constrained.
WASP-24 has an apparent magnitude
Apparent magnitude
The apparent magnitude of a celestial body is a measure of its brightness as seen by an observer on Earth, adjusted to the value it would have in the absence of the atmosphere...
of 11.3. It cannot be seen from Earth with the naked eye
Naked eye
The naked eye is a figure of speech referring to human visual perception unaided by a magnifying or light-collecting optical device, such as a telescope or microscope. Vision corrected to normal acuity using corrective lenses is considered "naked"...
.
Characteristics
WASP-24b is a Hot JupiterHot Jupiter
Hot Jupiters are a class of extrasolar planet whose mass is close to or exceeds that of Jupiter...
that has a mass of 1.032 times the mass
Jupiter mass
Jupiter mass , is the unit of mass equal to the total mass of the planet Jupiter . Jupiter mass is used to describe masses of the gas giants, such as the outer planets and extrasolar planets. It is also used in describing brown dwarfs....
of Jupiter. Its radius is 1.104 times the radius of Jupiter. In addition, with a mean distance of 0.0359 AU
Astronomical unit
An astronomical unit is a unit of length equal to about or approximately the mean Earth–Sun distance....
between it and its star, where one AU is the average distance between the Earth and the Sun, WASP-24b completes an orbit every 2.3412083 days (roughly 57 hours). In comparison, Mercury
Mercury (planet)
Mercury is the innermost and smallest planet in the Solar System, orbiting the Sun once every 87.969 Earth days. The orbit of Mercury has the highest eccentricity of all the Solar System planets, and it has the smallest axial tilt. It completes three rotations about its axis for every two orbits...
orbits the Sun every 87.97 days at a distance of 0.387 AU.
WASP-24b's orbital inclination is 83.64º, placing WASP-24b almost edge-on with respect to Earth and to its host star.