Mortal as I am, I know that I am born for a day. But when I follow at my pleasure the serried multitude of the stars in their circular course, my feet no longer touch the earth - Ptolemy
Russian rocket disaster
The unmanned Progress M-12M cargo ship which was due to replenish supplies on the ISS did not reach the correct orbit after launch and fell back to Earth. On board were three tonnes of supplies including food, but the loss is not detrimental to the astronauts on board the ISS as the last Space Shuttle flight delivered enough food to last them approximately a year. The current crew may be asked to remain on board the ISS for longer than scheduled and that will create a medical issue. Astronauts are only allowed to work on the space station for a certain length of time to limit their exposure to the intense radiation from the Sun. An investigation has been launched to discover the cause of the failure of the robotic rocket.
Mira - an important star
The first variable star to be discovered was omicron Ceti, commonly named Mira (Latin meaning 'the amazing one'). It fluctuates between first and tenth magnitude, making it one of the brightest periodic variables. Mira's strange behaviour pattern, including disappearing from view for part of its cycle, led astronomers to mistakenly assume it was a nova (exploding star). At the time of its scientific discovery in 1596, most people had a geocentric world-view (in which the Earth is at the centre of the universe and every other heavenly body revolved around it). To voice a different theory was considered heresy and many people, including philosopher Giordano Bruno, died for their beliefs. The study of Mira added to the weight of evidence which eventually led towards the now scientifically-accepted heliocentrism. This month Mira will reach its maximum brightness, putting it on par with the likes of Aldebaran, Arcturus, Betelgeuse and Sirius. Mira is a red giant star so even though it is 420 light years away it will appear as bright as those familiar stars to us.
September 2011 Diary Dates
- 01: Comet Garradd close to the Coathanger asterism in Vulpecula
- 04: First quarter Moon above Antares (alpha Scorpii)
- 09: Piscids meteor shower peak
- 12: Full Moon (the Harvest Moon) in the Circlet (another asterism) of Pisces
- 13: Mira (omicron Ceti) could reach 1st magnitude
- 17: Moon near The Pleiades
- 23: Mars 5° north of Moon
- 23: Autumn equinox (Northern Hemisphere)
- 25: Last crescent Moon near Regulus (alpha Leonis)
- 27: New Moon
- 30: Mars passes through Messier 44 ('Praesepe' aka the Beehive Cluster in Cancer)
Chat about your celestial observances at the H2G2 Astronomy Society. Comment on anything in this edition of Babe Among the Stars by starting a new conversation below.