In the show this time, Maria del Mar Rubio tells us about mass loss in massive stars, Dr Gemma Janssen talks about a new method for pulsar timing in this month's JodBite, and your astronomical questions are answered by Dr Michael Brown in Ask an Astronomer.
JodBite with Dr Gemma Janssen
Dr Gemma Janssen is a postdoctoral research assistant at the Jodrell Bank Centre for Astrophysics. Gemma's research involves the detection of gravitational waves using pulsar timing. Though detected indirectly three decades ago, the direct detection of gravitational waves has remained elusive. The Large European Array for Pulsars (LEAP) project is currently using five radio telescopes together as a phased array telescope for high-precision pulsar timing, with the goal of making the first direct detection.
Interview with Maria del Mar Rubio
Maria del Mar Rubio is a PhD student at the Centro de Astrobiologia, Spain. In this interview she tells us about stellar winds in massive stars, and how the mass-loss rates of luminous OB stars are inferred from several types of measurement. These mass-loss rates may need to be revised when clumping in the wind is taken into account, using state-of-the-art models.
Ask an Astronomer
Dr Michael Brown answers your astronomical questions:
- The first question comes from Mark Foskey, who says: "I frequently hear it explained that the Universe consists of about 5% regular matter, 23% dark matter and 72% dark energy. How is this bookkeeping done?"
- The second question is from Richard Elvin, who asks: "Can the temperature and pressure in a black hole's accretion disc reach sufficient levels to ignite nuclear fusion? Is this what powers an active galactic nucleus?"
Odds and Ends
A team from the Harvard-Smithsonian Center for Astrophysics has analysed data from the planet-hunting Kepler space telescope and now estimate that 6% of all red dwarf stars in our galaxy may have Earth-sized planets in the habitable zone of their systems. With some 75 billion red dwarfs in our galaxy, they estimate that these Earth-like planets would be only 13 light years apart from each other on average.
3D printers may be used to set up a lunar base. Architects Foster + Partners have joined with ESA to test the possibility of 3D printing using lunar soil. The firm devised a weight-bearing dome designed to shield against micrometeoroids and space radiation.
A group of small meteorites may have come to Earth from the planet Mercury, according to recent chemical analysis. Information from the Messenger spacecraft suggests that Mercury's surface has a smiliar composition to the meteorites, which are unlike any others yet found. A mission to the Mercurial surface may be a long way off, but it could be the only way to confirm whether we now have the first known meteorites from Mercury.
|JodBite:||Dr Gemma Janssen and Philippa Hartley|
|Interview:||Maria del Mar Rubio and Libby Jones|
|Ask An Astronomer:||Dr Michael Brown and Liz Guzman|
|Presenters:||Liz Guzman, Mark Purver, and Hector Vives|
|Editors:||Dan Thornton, Sally Cooper, Mark Purver and Christina Smith|
|Segment Voice:||Mike Peel|
|Website:||Mark Purver and Stuart Lowe|
|Cover art:||The Lovell Telescope, one part of the phased array telescope synthesised by the Large European Array for Pulsars project. CREDIT: Jodrell Bank Centre for Astrophysics, The University of Manchester|