Bakersfield Night Sky – November 18, 2017
By Nick Strobel
The closest star to our solar system, a small red-dwarf star called Proxima Centauri might have another planet besides the one discovered last year in August. The first planet found orbiting Proxima Centauri resides in Proxima’s habitable zone and is slightly bigger than Earth. The latest findings are from a team that used the super-powerful ALMA observatory in Chile that observes in the millimeter and sub-millimeter wavelengths. At these wavelengths cold dust and molecular clouds glow most strongly. The array of 66 high-precision antennae observes objects at these wavelengths with very high resolution—ten times better than the Hubble Space Telescope.
The team led by Guillem Anglada from Spain pointed ALMA at Proxima Centauri to see if it had a cold, dusty belt circling further out from Proxima than the planet that would be similar to the Kuiper Belt that exists around our sun just outside the orbit of Neptune. Sure enough, Proxima Centauri has a dust belt around it. After a while the dust would get cleared out unless something like a planet is around to stir up the small rocks and get them to collide with each to replenish the dust stock. There is the hint of the dust disk being lopsided which might be due to a planet embedded within the disk. This is similar to the misshapen dust belt around the bright star Fomalhaut that we now know is due to a large planet orbiting Fomalhaut. There will definitely be more observations of Proxima Centauri!
A couple of other interesting stories are not astronomy research but, rather related to the International Space Station (ISS). The first is right in our own backyard at NASA’s Armstrong Flight Research Center at Edwards. Last Saturday, Sierra Nevada Corporation had a successful free-flight test of their Dream Chaser spacecraft. Looking like a miniature space shuttle, the craft will be able to haul up to 12,125 pounds of cargo up to the ISS beginning in 2019. That will bring to three, the number of companies able to fly delivery missions for NASA (the other two are SpaceX and Orbital ATK).
The second is about the farming operation on ISS. There are now three distinct plant crops growing on ISS. It is more a proof of concept operation than something the astronauts could live off of but they were able to harvest some of the greens at the end of October for some salad. The greens are Mizuna mustard, Waldmann’s green lettuce and Outredgeous Red Romaine lettuce. Besides the nutrition benefits of fresh green leafy vegetables, the plants give a psychological boost to astronauts aboard ISS. The plants are a direct tangible link to Earth for the astronauts who spend weeks to months far from friends and family and the rest of humanity.
The knowledge we gain from the ISS farm operation will be critical for human flights to and living on Mars as well any base we may establish on the moon. Although we think we are such advanced, rational beings, we are also social beings with emotional and instinctual ties to our home planet that we can’t just turn off like a robot can. Having the greenery that we can touch and eat will go a long, long way to keeping off-world humans sane. Furthermore, the bases on the moon and Mars will need to be self-sufficient, not getting deliveries from Earth like we can do for ISS. We’re also learning what microbes are necessary to grow plants away from Earth. In addition the plants can help convert the carbon dioxide we breathe out into the oxygen we breathe in.
Back here on Earth, more specifically, Bakersfield, tickets are on sale for the traditional holiday showings of “Season of Light” at the William M Thomas Planetarium on November 30 and December 7. After a tour of the evening sky, we’ll look at the origin of many of our holiday traditions and rituals we observe around the winter solstice— not only Christian and Jewish, but also Celtic, Nordic, Roman, Irish, Mexican and Hopi. “Season of Light” also explains the astronomy of the winter solstice and ends with possible astronomical explanations for the “Star of Bethlehem”. All throughout is great music, so come enjoy a night under the stars!
Two nights from now (on Nov 20), look for a thin waxing crescent moon just to the right of Saturn just after sunset (see the first chart below). Using binoculars you may be able to spot Mercury one-and-a-half fields of view below the moon and Saturn. At the end of the month you’ll see Mercury even closer to Saturn. On Thanksgiving the moon will be a fat crescent in the southwest after sunset. First Quarter is on November 26.
Director of the William M Thomas Planetarium at Bakersfield College
Author of the award-winning website www.astronomynotes.com