The Night Sky This Month: November 2016

The Leonids

Constellations

In the early evening, the “Summer Triangle” consisting of the brightest stars in Cygnus, Lyra and Aquila appears in the southern sky before moving overhead and traveling progressively westwards as the night advances. To this asterism’s east can be found the constellations of Pegasus and Andromeda, which also contains the beautiful Andromeda Nebula (M31).

Looking further north can be found Cassiopeia and Perseus, while rising in the east during the latter part of the evening can be seen the constellation of Taurus, complete with its two striking star clusters, the Hyades and Pleiades. The winter constellation of Orion also rises to prominence in the east as the night progresses.

Meteor Showers

November offers two meteor showers, the first being the Northern Taurids that peak on about the 10th of the month, and the more productive Leonids, that peak on the night of 17/18 November. Below are some more details:

– The Northern Taurids are associated with comet 2P/Encke, and this year, Earth will be passing through a part of its debris trail that is particularly rich in large particles, which means that observers should see some spectacularly bright meteors, if not actual fireballs, in the hours between moonset and dawn. This shower is active for around 10 days, and although it is not known to be very productive, the lack of bright moonlight after the 7th should make for good meteor spotting conditions.

– The Leonids are associated with the comet 55P/Temple-Tuttle, but sadly, no more than about 15 or so meteors per hour are expected this year. This year, the Leonids fall midway in its 33-year cycle between maximums, which means that a repeat of the 1999 event when more than 3 000 meteors per hour were seen will only happen again in about 15 to 16 years’ time. Furthermore, the peak will occurs when the Moon is still nearly full, meaning that in 2016 the Leonids are unlikely to produce quite as spectacular a celestial event as seen in past years.

The Moon

Hadley Rille Since the month of November does not offer much in the way of planetary viewing this year, it might be more profitable to spend time learning about the Maria, or “oceans of stone” on the near side of Moon. The Maria, Latin for “Seas”, are vast impact basins that were flooded with lava in the Moon’s distant past, but much can still be learned about the geological evolution of the Moon by observing, and studying the fractures, rilles, and other features in and around the edges of any Mare.

The image below shows one of the more famous rilles, aka collapsed lava tubes, on the Moon; the famous Hadley Rille running along the south-eastern rim of the Mare Imbrium. While the lava tubes on Hawaii are similar in structure and origin, this particular Rille became famous because Apollo 15 landed close to it.

Moon Phases

New Moon: 29th
First Quarter: 7th
Full Moon: 14th
Last Quarter: 21st

The Planets

– Mercury only becomes visible low on southwestern horizon by the third week of the month, but it will gain some altitude as it approaches a position of maximum elongation from the Sun, which position it reaches around the middle of December. Given clear skies, it might just be possible to spot Mercury on the 23rd of the month, when it will be close to Venus.

Venus starts November setting in the west around 2 hours after the Sun, but sets progressively later until by month’s end, it will set around 3 hours after the Sun. During the month, the planets’ brightness will increase from magnitude -4.0 to -4.2, but since its phase will decrease from 78% to 70%, its overall brightness will remain largely unchanged throughout the month. Look for Venus as it moves eastward out of Ophiuchus on the 9th, and into Sagittarius, where on the 17th of the month, it will be just 7.5 minutes of arc below Lamda Sagittarri, the 2.8 magnitude star that marks out the “lid” of the Teapot asterism.

– Mars is now racing eastward through the constellations Sagittarius and Capricornus, but as it does, it dims from magnitude +0.4 to +0.6. While it is still (barely) visible low on the southern horizon, its angular diameter of only about 7 seconds arc makes it too small for any surface detail to be visible.

Jupiter is now the only pre-dawn planet in the sky, rising about 2.5 hours before the Sun at the beginning of the month. As the month wears on however, it will rise progressively earlier, to rise at about 2:20 UT (GMT) by month’s end. Early risers should be able to find the King of the Planets about 20 or so degrees above the southeastern horizon during the first days of the month, and about 10 degrees higher during the last week of November. Even though Jupiter is now smaller and dimmer that it has been in a long while, it still shines at a magnitude of -1.7 and shows a disc 32 arc seconds across, which should make it easy to spot in the constellation Virgo.

-Saturn might still be visible to observers in the southern reaches of the UK, around 10 degrees above the southwestern horizon, but as the month wears on, it will sink lower towards the elliptic, effectively rendering it invisible for most observers in the northern hemisphere for the next several years. Observers who want to get a last, good look at Saturn can look for it in the southern reaches of the constellation Ophiuchus, about 7 degrees or so to the upper leftward of the star Antares in the constellation Scorpius.