Hubble spots ‘waterworld’ circling red-dwarf star
The State Column | Tuesday, February 21, 2012
NASA’s Hubble Space Telescope has spotted a new class of planet, a “waterworld” concealed by a soupy, vaporous atmosphere, according to a press release from HubbleSite. Scientists claim that the “waterworld,” or planet GJ1214b, is smaller than Uranus but bigger than Earth.
Zachory Berta of the Harvard-Smithsonian Center for Astrophysics (CfA) and his colleagues used NASA’s Hubble Space Telescope to spot the “waterworld.”
“GJ1214b is like no planet we know of,” Mr. Berta posited. “A huge fraction of its mass is made up of water,” he added.
The MEarth Project, which is headed up by CfA’s David Charbonneau, located the “waterworld” back in 2009. Scientists estimate that the “waterworld” is about 2.7 times Earth’s diameter and weighs nearly 7 times as much. Unlike the Earth, which orbits the Sun once a year, the “waterworld” orbits a red-dwarf star every 38 hours. Planet GJ1214b is 1.3 million miles away from the red-dwarf star, which means that it has a temperature of approximately 450 degrees Fahrenheit.
Mr. Charbonneau and his team of researchers first submitted a study titled “A super-Earth transiting a nearby low-mass star” in 2009. “We find that the planetary mass and radius are consistent with a composition of primarily water enshrouded by a hydrogen-helium envelope that is only 0.05% of the mass of the planet,” the abstract read. “As the star is small and only 13 parsecs away, the planetary atmosphere is amenable to study with current observatories,” the researchers added and over the next three years the team of scientists carefully examined the “waterworld.”
In 2010, CfA scientist Jacob Bean and his colleagues revealed that they had examined the atmosphere of the “waterworld,” reporting that it was primarily made up of water. The HubbleSite press release suggests that this observation could have been made based on the soupy, vaporous atmosphere of the “waterworld.”
Before Mr. Berta and his researchers had access to the Hubble Space Telescope’s Wide Field Camera 3 (WFC3), the team was limited as to what they could do to determine whether the planet was surrounded by haze or water vapor.
The researchers noted this predicament in the journal Nature back in December 2010: “In contrast to planets with masses similar to that of Jupiter and higher, the bulk compositions of planets in the so-called super-Earth regime (masses 2–10 times that of the Earth) cannot be uniquely determined from a measurement of mass and radius alone.”
Mr. Berta and the co-authors of the study deployed the WFC3 to study GJ1214b when it crossed in front of its host star. During such a transit, the star’s light is filtered through the planet’s atmosphere, providing evidence about the mix of gases.
“We’re using Hubble to measure the infrared color of sunset on this world,” Mr. Berta posited.
According to HubbleSite, hazes appear more transparent when exposed to infrared light than visible light so the Hubble Space Telescope is able to pinpoint the difference between a steamy and a hazy atmosphere.
Scientists contend that a thorough analysis of data from the Hubble Space Telescope suggests that planet GJ1214b has a dense atmosphere of water vapor.
“The Hubble measurements really tip the balance in favor of a steamy atmosphere,” Mr. Berta professed.
Researchers believe that the “waterworld” has a density of only about 2 grams per cubic centimeter, which means that GJ1214b has a lot more water than Earth does. Scientists believe that the density of the “waterworld” corresponds to an internal structure that would be vastly different than Earth’s.
“The high temperatures and high pressures would form exotic materials like ‘hot ice’ or ‘superfluid water,’ substances that are completely alien to our everyday experience,” Mr. Berta said.
Scientists believe that GJ1214b has migrated closer to its star over time. As the waterworld moved closer to its star, it would have passed through a habitable zone. However, the temperature on planet GJ1214b eventually grew to hot for habitation.
The “waterworld” is located in the direction of the constellation Ophiuchus. Due to the fact that the new exoplanet is only 40 light-years from Earth, it is likely that it will be studied by the James Webb Space Telescope at some point in the future. Unfortunately, the James Webb Space Telescope is not scheduled to launch until 2018.
A study with additional details of the discovery has been published in The Astrophysical Journal.
Read more: http://www.thestatecolumn.com/articles/2012/02/21/hubble-spots-waterworld-circling-red-dwarf-star/#ixzz1n5Y3N7rl
NASA’s Hubble Space Telescope has spotted a new class of planet, a “waterworld” concealed by a soupy, vaporous atmosphere, according to a press release from HubbleSite. Scientists claim that the “waterworld,” or planet GJ1214b, is smaller than Uranus but bigger than Earth.
Zachory Berta of the Harvard-Smithsonian Center for Astrophysics (CfA) and his colleagues used NASA’s Hubble Space Telescope to spot the “waterworld.”
“GJ1214b is like no planet we know of,” Mr. Berta posited. “A huge fraction of its mass is made up of water,” he added.
The MEarth Project, which is headed up by CfA’s David Charbonneau, located the “waterworld” back in 2009. Scientists estimate that the “waterworld” is about 2.7 times Earth’s diameter and weighs nearly 7 times as much. Unlike the Earth, which orbits the Sun once a year, the “waterworld” orbits a red-dwarf star every 38 hours. Planet GJ1214b is 1.3 million miles away from the red-dwarf star, which means that it has a temperature of approximately 450 degrees Fahrenheit.
Mr. Charbonneau and his team of researchers first submitted a study titled “A super-Earth transiting a nearby low-mass star” in 2009. “We find that the planetary mass and radius are consistent with a composition of primarily water enshrouded by a hydrogen-helium envelope that is only 0.05% of the mass of the planet,” the abstract read. “As the star is small and only 13 parsecs away, the planetary atmosphere is amenable to study with current observatories,” the researchers added and over the next three years the team of scientists carefully examined the “waterworld.”
In 2010, CfA scientist Jacob Bean and his colleagues revealed that they had examined the atmosphere of the “waterworld,” reporting that it was primarily made up of water. The HubbleSite press release suggests that this observation could have been made based on the soupy, vaporous atmosphere of the “waterworld.”
Before Mr. Berta and his researchers had access to the Hubble Space Telescope’s Wide Field Camera 3 (WFC3), the team was limited as to what they could do to determine whether the planet was surrounded by haze or water vapor.
The researchers noted this predicament in the journal Nature back in December 2010: “In contrast to planets with masses similar to that of Jupiter and higher, the bulk compositions of planets in the so-called super-Earth regime (masses 2–10 times that of the Earth) cannot be uniquely determined from a measurement of mass and radius alone.”
Mr. Berta and the co-authors of the study deployed the WFC3 to study GJ1214b when it crossed in front of its host star. During such a transit, the star’s light is filtered through the planet’s atmosphere, providing evidence about the mix of gases.
“We’re using Hubble to measure the infrared color of sunset on this world,” Mr. Berta posited.
According to HubbleSite, hazes appear more transparent when exposed to infrared light than visible light so the Hubble Space Telescope is able to pinpoint the difference between a steamy and a hazy atmosphere.
Scientists contend that a thorough analysis of data from the Hubble Space Telescope suggests that planet GJ1214b has a dense atmosphere of water vapor.
“The Hubble measurements really tip the balance in favor of a steamy atmosphere,” Mr. Berta professed.
Researchers believe that the “waterworld” has a density of only about 2 grams per cubic centimeter, which means that GJ1214b has a lot more water than Earth does. Scientists believe that the density of the “waterworld” corresponds to an internal structure that would be vastly different than Earth’s.
“The high temperatures and high pressures would form exotic materials like ‘hot ice’ or ‘superfluid water,’ substances that are completely alien to our everyday experience,” Mr. Berta said.
Scientists believe that GJ1214b has migrated closer to its star over time. As the waterworld moved closer to its star, it would have passed through a habitable zone. However, the temperature on planet GJ1214b eventually grew to hot for habitation.
The “waterworld” is located in the direction of the constellation Ophiuchus. Due to the fact that the new exoplanet is only 40 light-years from Earth, it is likely that it will be studied by the James Webb Space Telescope at some point in the future. Unfortunately, the James Webb Space Telescope is not scheduled to launch until 2018.
A study with additional details of the discovery has been published in The Astrophysical Journal.
Read more: http://www.thestatecolumn.com/articles/2012/02/21/hubble-spots-waterworld-circling-red-dwarf-star/#ixzz1n5Y3N7rl
