Artist’s concept of the super-Earth exoplanet Gliese 667 Cb.
Would that prove life exists there? Not necessarily, says a new study. The research team performed the simulation experiments in a specially designed Planetary HAZE ( PHAZER ) chamber in the lab of Sarah Hörst, assistant professor of Earth and Planetary Sciences and the paper’s co-author. Each mixture was exposed to two different kinds of energy – plasma and UV light – that can trigger chemical reactions in planetary atmospheres.
Our experiments produced oxygen and organic molecules that could serve as the building blocks of life in the lab, proving that the presence of both doesn’t definitively indicate life, says Chao He, assistant research scientist in the Johns Hopkins University Department of Earth and Planetary Sciences and the study’s first author. Nearly 4,000 exoplanets have been discovered so far, orbiting distant stars.
Scientists have been debating whether this planet has an atmosphere like Earth and Venus, or just a rocky core and no atmosphere, like Mercury. Researchers say the atmosphere of this mysterious planet could contain nitrogen, water and even oxygen – molecules found in our atmosphere, too – but with much higher temperatures throughout.
Understanding this planet will help us address larger questions about the evolution of rocky planets, Renyu Hu astronomer at NASA’s Jet Propulsion Laboratory, Pasadena, California, said.
Renyu Hu, astronomer and co-author of a study published in The Astronomical Journal, developed a method of studying exoplanet atmospheres and surfaces, and had previously only applied it to sizzling, giant gaseous planets called hot Jupiters.
Astrophysicists at the University of Toronto have found that a close encounter with Jupiter about four billion years ago may have resulted in another planet’s ejection from the Solar System altogether.
“Nitrogen isotopes tell a story about oxygenation of the surface ocean, and this oxygenation spans hundreds of kilometers across a marine basin and lasts for somewhere less than 50 million years” , said lead author Matt Koehler. “The deep ocean was likely anoxic, or without oxygen, at the time”. But the record of life on Earth is not confined to the Earth. But scientists are still sifting through the wealth of data Kaguya collected there. The team’s results are published in the October issue of The Astronomical Journal.
Imaginary Picture of Kepler-13 A b
Thomas Beatty, assistant research professor of astronomy at Penn State and the lead author of the study. Beatty’s team targeted planet Kepler-13Ab because it is one of the hottest of the known exoplanets. Its dayside temperature is nearly 5,000 degrees Fahrenheit. Even at their much colder temperatures, most of our solar system’s gas giants also have warmer temperatures at higher altitudes. The team notes that they made their discovery after examining how the host star’s light passed through the exoplanet’s atmosphere.
New results about potentially habitable exoplanets are always tantalizing. There are also pragmatic reasons for studying photosynthesis. But how similar to Earth might such distant worlds really be?
The researchers found evidence that both planets likely have seasons and stable climates, just as Earth does. It is one of five known planets in that planetary system and orbits within the habitable zone, even though its host star is a red dwarf. The axial variations of Earth have been largely kept in check by the Earth’s large moon, which Mars doesn’t have.
Illustration of the James Webb Space Telescope, current as of September 2009. Top side, public domain
Finding other Earth-like planets is the holy grail of exoplanet research. Water has been implied previously on individual exoplanets, but this work concludes that water-rich planets are common. It will have implications for the search of life in our Galaxy. The next generation space telescope, the James Webb Space Telescope, will hopefully characterize the atmosphere of some of them. Hopefully atmosphere observations in the future – of thick steam atmospheres – can support or refute the new findings.
NASA said its Hubble Space Telescope has discovered carbon dioxide in the atmosphere of “hot Jupiter” planet HD 189733b, which orbits a nearby star 63 light years from Earth. Mark Swain of NASA’s Jet Propulsion Laboratory in Pasadena, California, used Hubble’s near-infrared camera and multi-object spectrometer to study infrared light from the planet. Studying planets like GJ 1132b may help us understand Venus evolution. Today, the agency announced that a team of scientists has confirmed seven Earth-sized exoplanets orbiting TRAPPIST-1, a star located just 39 light-years away from our Sun. Three of the planets may even be able to support liquid water and perhaps, life.
Image Credit: – ESO / CC BY 4.0
