NASA Telescopes Detect Jupiter Like Storm on The Small Star - Astrophysicists have found what seems to be a small star with a giant, cloudy storm, by means of data from NASA's Spitzer and Kepler space telescopes. The dark storm is akin to Jupiter's Great Red Spot: a persistent, raging storm bigger than the Earth.
"The star is the size of Jupiter, and its storm is the size of Jupiter's Great Red Spot," said John Gizis of the University of Delaware, Newark. "We know this newly discovered storm has lasted at least two years, and possibly longer." Gizis is the lead author of a new study appearing in The Astrophysical Journal.
While planets have been known to have cloudy storms, this is the best proof yet for a star that has one. The star, called W1906+40, fits in to a thermally cool class of objects called L-dwarfs. Some L-dwarfs are considered stars as they fuse atoms and produce light, as our sun does, while others, called brown dwarfs, are known as "failed stars" for their lack of atomic fusion.
The L-dwarf in the study, W1906+40, is believed to be a star based on approximations of its age (the older the L-dwarf, the more probable it is a star). Its temperature is around 3,500 degrees Fahrenheit (2,200 Kelvin). That may sound scorching hot, but as far as stars go, it is comparatively cool. Cool enough, in fact, for clouds to form in its atmosphere.
"The L-dwarf's clouds are made of tiny minerals," said Gizis.
Spitzer has observed other cloudy brown dwarfs before, discovering evidence for short-lived storms lasting hours and possibly days.
In the new study, the astrophysicists were capable of studying variations in the atmosphere of W1906+40 for two years. The L-dwarf had primarily been discovered by NASA's Wide-field Infrared Survey Explorer in 2011. Later, Gizis and his team realized that this object happened to be situated in the same region of the sky where NASA's Kepler mission had been staring at stars for years to hunt for planets.
Kepler identifies planets by looking for dips in starlight as planets pass in front of their stars. In this case, astrophysicists knew observed dips in starlight weren't coming from planets, but they believed they might be looking at a star spot -- which, like our sun's "sunspots," are an outcome of concentrated magnetic fields. Star spots would also cause dips in starlight as they rotate about the star.
Follow-up observations with Spitzer, which detects infrared light, revealed that the dark patch was not a magnetic star spot but a colossal, cloudy storm with a diameter that could hold three Earths. The storm rotates around the star approximately every 9 hours. Spitzer's infrared measurements at two infrared wavelengths probed different layers of the atmosphere and, together with the Kepler visible-light data, helped reveal the existence of the storm.
While this storm looks different when observed at various wavelengths, astrophysicists say that if we could somehow travel there in a starship, it would look like a dark mark near the polar top of the star.
The scientists plan to look for other stormy stars and brown dwarfs using Spitzer and Kepler in the future.
"We don't know if this kind of star storm is exceptional or common, and we don't why it persists for so long," said Gizis.
"The star is the size of Jupiter, and its storm is the size of Jupiter's Great Red Spot," said John Gizis of the University of Delaware, Newark. "We know this newly discovered storm has lasted at least two years, and possibly longer." Gizis is the lead author of a new study appearing in The Astrophysical Journal.
While planets have been known to have cloudy storms, this is the best proof yet for a star that has one. The star, called W1906+40, fits in to a thermally cool class of objects called L-dwarfs. Some L-dwarfs are considered stars as they fuse atoms and produce light, as our sun does, while others, called brown dwarfs, are known as "failed stars" for their lack of atomic fusion.
The L-dwarf in the study, W1906+40, is believed to be a star based on approximations of its age (the older the L-dwarf, the more probable it is a star). Its temperature is around 3,500 degrees Fahrenheit (2,200 Kelvin). That may sound scorching hot, but as far as stars go, it is comparatively cool. Cool enough, in fact, for clouds to form in its atmosphere.
"The L-dwarf's clouds are made of tiny minerals," said Gizis.
Spitzer has observed other cloudy brown dwarfs before, discovering evidence for short-lived storms lasting hours and possibly days.
In the new study, the astrophysicists were capable of studying variations in the atmosphere of W1906+40 for two years. The L-dwarf had primarily been discovered by NASA's Wide-field Infrared Survey Explorer in 2011. Later, Gizis and his team realized that this object happened to be situated in the same region of the sky where NASA's Kepler mission had been staring at stars for years to hunt for planets.
Kepler identifies planets by looking for dips in starlight as planets pass in front of their stars. In this case, astrophysicists knew observed dips in starlight weren't coming from planets, but they believed they might be looking at a star spot -- which, like our sun's "sunspots," are an outcome of concentrated magnetic fields. Star spots would also cause dips in starlight as they rotate about the star.
Follow-up observations with Spitzer, which detects infrared light, revealed that the dark patch was not a magnetic star spot but a colossal, cloudy storm with a diameter that could hold three Earths. The storm rotates around the star approximately every 9 hours. Spitzer's infrared measurements at two infrared wavelengths probed different layers of the atmosphere and, together with the Kepler visible-light data, helped reveal the existence of the storm.
While this storm looks different when observed at various wavelengths, astrophysicists say that if we could somehow travel there in a starship, it would look like a dark mark near the polar top of the star.
The scientists plan to look for other stormy stars and brown dwarfs using Spitzer and Kepler in the future.
"We don't know if this kind of star storm is exceptional or common, and we don't why it persists for so long," said Gizis.
No comments