metal-poor stars tagged posts

In a new study, astronomers report novel evidence regarding the limits of planet formation, finding that after a certain point, planets larger than Earth have difficulty forming near low-metallicity stars.

Using the sun as a baseline, astronomers can measure when a star formed by determining its metallicity, or the level of heavy elements present within it. Metal-rich stars or nebulas formed relatively recently, while metal-poor objects were likely present during the early universe.

Previous studies found a weak connection between metallicity rates and planet formation, noting that as a star’s metallicity goes down, so, too, does planet formation for certain planet populations, like sub-Saturns or sub-Neptunes.

Yet this work is the first to observe that under current theories...

A star’s chemical composition strongly influences the ultraviolet radiation it emits into space and thus the conditions for the emergence of life in its neighborhood.

Stars that contain comparatively large amounts of heavy elements provide less favourable conditions for the emergence of complex life than metal-poor stars, as scientists from the Max Planck Institutes for Solar System Research and for Chemistry as well as from the University of Göttingen have now found. The team showed how the metallicity of a star is connected to the ability of its planets to surround themselves with a protective ozone layer. Crucial to this is the intensity of the ultraviolet light that the star emits into space, in different wavelength ranges...

The plane of our Galaxy as seen in infrared light from the WISE satellite. The bulge is a distinct component and most of its mass resides in a boxy/peanut bulge, which is in cylindrical rotation. An ancient population, estimated to be 1% of the mass of the bulge, has been detected kinematically detected in the inner Milky Way and does not cylindrically. Instead, this population is likely to have been one of the first parts of the Milky Way to form. Credit: NOAO/AURA/NSF/AIP/A. Kunder

An international team has discovered that the central 2000 light years within the Milky Way Galaxy hosts an ancient population of stars >10 billion years old and their orbits in space preserve the early history of the formation of the Milky Way...