Category Astronomy/Space

Exoplanets similar to Earth.
Credit: NASA

Scientists have shown that water is likely to be a major component of those exoplanets (planets orbiting other stars) which are between 2 to 4X the size of Earth. It will have implications for the search of life in our Galaxy. The work is presented at the Goldschmidt conference in Boston.

The 1992 discovery of exoplanets orbiting other stars has sparked interest in understanding the composition of these planets to determine, among other goals, whether they are suitable for the development of life. Now a new evaluation of data from the exoplanet-hunting Kepler Space Telescope and the Gaia mission indicates that many of the known planets may contain as much as 50% water. This is much more than the Earth’s 0.02% (by weight) water content...

Planetary nebula HuBi 1 (left) and another planetary nebula Abell39 (right, 6800 light years away from our solar system). Abell39 is an archetypal, textbook case of a spherical nebula surrounding a bright central star (a white dwarf), its nebula composes of hydrogen-rich ionized gas. HuBi 1, its central star has undergone a “born-again” event ejecting metal-rich material into the old, hydrogen-rich nebula, has a double-shell structure – a hydrogen-rich outer shell and a nitrogen-rich inner shell.
Credit: (HuBi 1 image adopted from Guerrero, Fang, Miller Bertolami, et al., 2018, Nature Astronomy, tmp, 112. Image credit for Abell39: The 3.5m WIYN Telescope, National Optical Astronomical Observatory, NSF. URL: https://www.noao.edu)

International team discovers an inside-out nebula surrounds a ...

Oldest rock on Earth: Acasta River gneiss (stock image). Credit: © Xenomanes / Fotolia

Scientists have found that 4.02-billion-year-old silica-rich felsic rocks from the Acasta River, Canada – the oldest rock formation known on Earth – probably formed at high temperatures and at a surprisingly shallow depth of the planet’s nascent crust. The high temperatures needed to melt the shallow crust were likely caused by a meteorite bombardment around half a billion years after the planet formed. This melted the iron-rich crust and formed the granites we see today. These results are presented for the first time at the Goldschmidt conference in Boston (14 August), following publication in the peer-reviewed journal Nature Geoscience.

The felsic rocks (rocks rich in silica/quartz) found at the Acast...

Artist’s view of a sunset over KELT-9b. The nearby warm blue star covers 35° in the planet’s sky, about 70 times the apparent size of the sun in the Earth’s sky. Under this scorching sun, the planet’s atmosphere is warm enough to shine in reddish-orange tones and vaporize heavy metals such as iron and titanium. Credit: Denis Bajram Read more at: https://phys.org/news/2018-08-iron-titanium-atmosphere-exoplanet.html#jCp

Metal vapors have been detected in the atmosphere of an ‘ultra-hot Jupiter’ by a team of astronomers. Exoplanets, planets in other solar systems, can orbit very close to their host star. When, in addition to this, the host star is much hotter than our Sun, then the exoplanet becomes as hot as a star...