Frank Elmore Ross (1874-1960), an American astronomer and physicist, became the successor to E. E. Barnard at Yerkes Observatory. Barnard, of course, is the discoverer of the high proper motion of the star named after him, alerting us to its proximity. And as his successor, Ross would go on to catalog over 1000 stars with high proper motion, many of them nearby. Ross 128, now making news for what observers at the Arecibo Observatory are calling "broadband quasi-periodic non-polarized pulses with very strong dispersion-like features," is one of these, about 11 light years out in the direction of Virgo. Any nearby stars are of interest from the standpoint of exoplanet investigations, though thus far we've yet to discover any companions around Ross 128. An M4V dwarf, Ross 128 has about 15 percent of the Sun's mass. More significantly, it is an active flare star, capable of unpredictable changes in luminosity over short periods. Which leads me back to that unusual reception. The SETI...

‘Planetary mass binary’ is an unusual term, but one that seems to fit new observations of what was thought to be a brown dwarf or free-floating large Jupiter analog, and now turns out to be two objects, each of about 3.7 Jupiter masses. That puts them into planet-range when it comes to mass, as the International Astronomical Union normally considers objects below the minimum mass to fuse deuterium (13 Jupiter masses) to be planets. This is the lowest mass binary yet discovered. A team led by William Best (Institute for Astronomy, University of Hawaii) went to work on the L7 dwarf 2MASS J11193254–1137466 with the idea of determining what they assumed to be the single object’s mass and age. It was through observations with the Keck II telescope in Hawaii that they discovered the binary nature of their target. The separation between the two objects is about 3.9 AU, based upon the assumption that the binary is around 160 light years away, the distance of the grouping of stars called the...

Our theories of planet formation grow more mature as the exoplanet census continues, but I've always speculated about the first planets discovered and how they could have possibly been where we found them. The discovery of the planets around the pulsar PSR B1257+12 occurred in 1992, the work of the Polish astronomer Aleksander Wolszczan. Anomalies in its pulsation period -- this is a millisecond pulsar with a period of 6.22 milliseconds -- led Wolszczan and Dale Frail to produce a paper on the first extrasolar planets ever found. We wouldn't find such planets at all if it were not for the effect of their gravitational pull on the otherwise regular pulses from the pulsar. But how could the planets now know as Draugr, Poltergeist and Phobetor, the latter found in 1994, possibly have formed in such an environment? After all, a dense neutron star (a pulsar is a highly magnetized, rotating neutron star) is the result of a supernova that should have destroyed any planets nearby, making it...

Interesting news keeps coming out of the National Astronomy Meeting in the UK. Today it involves brown dwarfs and their distribution throughout the galaxy, a lively question given how recently we’ve begun to study these ‘failed stars.’ Maybe we need a better name than ‘brown dwarfs,’ for that matter, since these objects are low enough in mass that they cannot sustain stable hydrogen fusion in their core. In a murky intermediary zone between planet and star, they can produce planets of their own but straddle all our contemporary definitions. At the NAS meeting, an international team led by Koraljka Muzic (University of Lisbon) has reported on its work on brown dwarfs in clusters. It seems a sensible approach -- go to the places where young stars are forming and try to figure out how many brown dwarfs emerge alongside them. That could help to give us an overview, because the brown dwarfs we’ve already found (beginning with the first, in 1995) are generally within 1500 light years of...

The prospects for life around M-dwarf stars, always waxing and waning depending on current research, have dimmed again with the release of new work from Christina Kay (NASA GSFC) and colleagues. As presented at the National Astronomy Meeting at the University of Hull (UK), the study takes on the question of space weather and its effect on habitability. We know that strong solar flares can disrupt satellites and ground equipment right here on Earth. But habitable planets around M-dwarfs -- with liquid water on the surface -- must orbit far closer to their star than we do. Proxima Centauri b, for example, is roughly 0.05 AU from its small red host (7,500,000 km), while all seven of the TRAPPIST-1 planets orbit much closer than Mercury orbits the Sun. What, then, could significant flare activity do to such vulnerable worlds? Image: Artist’s impression of HD 189733b, showing the planet’s atmosphere being stripped by the radiation from its parent star. Credit: Ron Miller. Working with...