Habitable Zones & Global Climate: December 2013

We explore the general astrobiological significance of F-type main-sequence stars with masses between 1.2 and 1.5 Msun.

To date, scientists have confirmed the existence of more than 900 exoplanets circulating outside our solar system.

Earth's volatile elements (H, C, and N) are essential to maintaining habitable conditions for metazoans and simpler life forms.

The habitable zone (HZ) around a star is typically defined as the region where a rocky planet can maintain liquid water on its surface.

We present the results of simulations on the detectability of O2 in the atmosphere of Earth twins around nearby low mass stars using high resolution transmission spectroscopy.

In the redshift range 100<(1+z)<110, the cosmic microwave background (CMB) had a temperature of 273-300K (0-30 degrees Celsius), allowing early rocky planets (if any existed) to have liquid water chemistry on their surface and be habitable, irrespective of their distance from a star.

Using the powerful eye of NASA's Hubble Space Telescope, two teams of scientists have found faint signatures of water in the atmospheres of five distant planets.

The future biosphere on Earth (as with its past) will be made up predominantly of unicellular microorganisms.