A cloudy super-Earth is raising questions.
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Science Recorder | Delila James | Wednesday, January 01, 2014
Astronomers are having a tough time figuring out what some super-Earths are made of–thanks to layers of high-altitude clouds blanketing the planets.
The name “super-Earth” is just a bit misleading. In fact, these planets bear little resemblance to planet Earth. The term “super-Earth” only refers to the mass of the planet and doesn’t suggest anything
about its surface characteristics or potential for life.
Super-Earths are exoplanets–planets outside our solar system–that are larger than Earth but smaller than Neptune. And despite being rather common in our Milky Way, scientists still know very little about them. Super-Earths could be watery worlds or gas balls like Jupiter with atmospheres similar to Earth’s or completely different. Unlocking their mysteries would not only enhance understanding of how planets and solar systems form, but help narrow down the search for intergalactic life forms.
In 2009, astronomers discovered a super-Earth exoplanet, classified as GJ 1214b, that is 2.7 times the size of Earth, a relatively nearby 40 light years away in the constellation Ophiuchus, and races around its red dwarf star once every 38 hours. The problem was, despite being otherwise well-suited for study, scientists remained puzzled because they couldn’t determine its composition.
Now, NASA’s Hubble Space Telescope is shedding some light (literally) on the mystery by allowing scientists to observe GJ 1214b as it passes in front of, or transits, its host star. This gives them the chance to study the planet as starlight filters through its atmosphere. The researchers look for changes in certain wavelengths of light, which indicate what chemicals are in the atmosphere, and for apparent changes in the planet’s observed size. For example, a watery world would make it look bigger because water vapor is opaque when seen through certain colored filters and blocks starlight.
Completely contrary to the research team’s expectations, even with Hubble’s precision, they observed no apparent change in the size of the planet. According to lead author Laura Kreidberg of the University of Chicago and her colleagues, this could only mean that GJ 1214b was blanketed in a cloud cover composed not of water, but of zinc sulfide or potassium chloride. The team’s paper is published in the journal Nature.
While it’s nice to have the mystery partly solved, the downside is that the planet’s clouds, like those here on Earth, reduce visibility. So, whether GJ 2114b is home to any sort of biological activity is likely to remain a mystery for the time being.
The name “super-Earth” is just a bit misleading. In fact, these planets bear little resemblance to planet Earth. The term “super-Earth” only refers to the mass of the planet and doesn’t suggest anything
about its surface characteristics or potential for life.
Super-Earths are exoplanets–planets outside our solar system–that are larger than Earth but smaller than Neptune. And despite being rather common in our Milky Way, scientists still know very little about them. Super-Earths could be watery worlds or gas balls like Jupiter with atmospheres similar to Earth’s or completely different. Unlocking their mysteries would not only enhance understanding of how planets and solar systems form, but help narrow down the search for intergalactic life forms.
In 2009, astronomers discovered a super-Earth exoplanet, classified as GJ 1214b, that is 2.7 times the size of Earth, a relatively nearby 40 light years away in the constellation Ophiuchus, and races around its red dwarf star once every 38 hours. The problem was, despite being otherwise well-suited for study, scientists remained puzzled because they couldn’t determine its composition.
Now, NASA’s Hubble Space Telescope is shedding some light (literally) on the mystery by allowing scientists to observe GJ 1214b as it passes in front of, or transits, its host star. This gives them the chance to study the planet as starlight filters through its atmosphere. The researchers look for changes in certain wavelengths of light, which indicate what chemicals are in the atmosphere, and for apparent changes in the planet’s observed size. For example, a watery world would make it look bigger because water vapor is opaque when seen through certain colored filters and blocks starlight.
Completely contrary to the research team’s expectations, even with Hubble’s precision, they observed no apparent change in the size of the planet. According to lead author Laura Kreidberg of the University of Chicago and her colleagues, this could only mean that GJ 1214b was blanketed in a cloud cover composed not of water, but of zinc sulfide or potassium chloride. The team’s paper is published in the journal Nature.
While it’s nice to have the mystery partly solved, the downside is that the planet’s clouds, like those here on Earth, reduce visibility. So, whether GJ 2114b is home to any sort of biological activity is likely to remain a mystery for the time being.
Read more: http://www.sciencerecorder.com/news/does-cloudy-super-earth-hold-life-weather-may-be-factor/#ixzz2pffUQpEA
