Observing

  • 01-10-2014

    Stargazing in November 2014

    The November Night Sky

    The General Weather patterns

    November continues with the weather pattern of October. Very occasionally an Indian summer will mellow the temperatures in the day, but the nights are then misty and foggy. Mostly, however, November is wet and temperature seldom fall below zero.

    From Earth

    Throughout this month, the ecliptic becomes steeper at sunset; rising from a shallow angle of about 18º at the beginning to about 26º at the end of the month, and evening twilight is shortening. Chilly nights are usual at this time of year so greater care should be taken to wrap up appropriately. The night skies are lengthening less rapidly now, and the Andromeda Galaxy is overhead in the best position to observe it mid-evening. The glorious winter skies are showing their promise with the arrival of Orion fully above the horizon by 21:30 in the middle of the month. The belt of Orion points north-west to the Pleiades and south-east to Sirius (below the horizon at this time) which will become available next month at a reasonable time in the evening.

    The Sun

    The Sun passes from Libra into Scorpius on the 24th and into Ophiuchus on the 30th of the month. Even though the Sun no longer reaches the elevation it does in the summer, it is worth reminding members that sunlight contains radiation across the spectrum that is harmful to our eyes and that the projection method should be used, or else, use the society’s solar telescope. Ask experienced members for help if you want to observe the Sun. If you attempt to observe Mercury and Saturn in the morning twilight, be very aware the Sun rises soon after.

    The Moon


    The Full Moon is on 6th at about 22:30 in the constellation of Ares.

    The Last Quarter is on 14th at about 15:15 in the constellation of Leo.

    The New Moon is on 22nd at about 12:30 in the constellation of Libra.

    The First Quarter is on 29th at about 10:00 in the constellation of Aquarius.

    The Moon is at perigee (nearest Earth) on the 27th and at apogee (most distant from Earth) on the 15th.

    The moon of course does the converse to the Sun and is culminating higher in the sky at night.

    The Planets

    Mercury -- is at greatest western elongation on the 1st and rises nearly two hours before the Sun. This is the best time to observe it this month.

    Venus -- is emerging from superior conjunction which occurred on the 25th October, closely following the Sun down and is not visible most of this month. Then again, you would be very fortunate to see it in the evening twilight at the end of the month.

    Mars -- is very poorly placed, low in the south-west at sunset, and follows the Sun down like this for the next eight months or so.

    Jupiter -- begins its evening appearances; rising before midnight on the 1st, and is becoming progressively more accessible in the morning sky. It can be found in the constellation of Leo. By the end of the month Jupiter will rise about 22:00. A photo-opportunity occurs when Jupiter rises with the last quarter Moon at midnight on the 24th. As opportunities for observing Jupiter improve, it is worth reminding members that there is much to see in a decent telescope. The Great Red Spot is visible, of course, even though it is much smaller than usual for some unknown reason, but also visible are the Galilean Moons with their accompanying shadows at this time. If you have good seeing you may well make out the belts too.

    Saturn -- is at conjunction on the 18th and is mostly unobservable this month. You would be very fortunate to see it in the morning twilight at the end of the month.

    Uranus -- is, in theory, a naked eye object with a magnitude of 5.71, but probably not with our skies. It can be found on the 15th culminating at about 21:30 in the constellation of Pisces at RA 0h 49m 29s, Declination 4º 33' 24". Binoculars, used at a dark site, should make the planet visible as a tiny greenish dot, about 42° above the horizon. On the 4th, in the evening twilight, the Moon passes just above and very close to Uranus providing a good opportunity to find Uranus without too much trouble.

    Neptune -- culminates 28° above the horizon at around 19:00 on the 15th of the month and can be observed at reasonable times throughout the month. It can be found at this time at RA 22h 27m 41s, Declination -10º 26' 39" (in Aquarius). With a magnitude of 7.88 you might like to use a telescope rather than binoculars.

    Meteors

    The Taurids can be seen emanating over the eastern horizon at sunset in the east from the 20th October to 30th November. Its maximum is wide-ranging, peaking around the 1st and 12th of November, with double radiants between Taurus and Aries. The Moon interferes with observations around the 12th this year, but the shower can produce slow, but brilliant meteors with a ZHR ~ 10 so don’t give up. This shower is associated with Comet P/Encke.

    The Leonids can be seen emanating over the eastern horizon at about 11:00 pm from the 15th to 20th November. Its maximum is on the night of the 17th/18th. With a ZHR ~ 15, the Leonids can provide very fast, magnificent displays, with persistent trains from its radiant around the neck of Leo. The rates are variable, but generally good. The Leonid meteor shower is not one of the best, but it does produce a spectacular meteor storm every 32/33 years when the Earth passes through its meteor swarm. Many thousands of meteors per hour can be seen for a short period of time, shooting across the sky. The next such storm is expected in the 2030s. The Leonids are associated with Comet P/Tempel-Tuttle.


    Cepheus (Pronounced Sea-Fee-us)

    Pegasus can be seen due south and high in the sky at around 22.00 in the middle of October, and is the most prominent constellation at this time of the year. The 'Square of Pegasus' consists of four second or third magnitude stars, and this vast asterism is fairly obvious because other bright stars are absent from inside the borders of the square. An interesting experiment is to count the number of stars you can see with and without a pair of binoculars.


    To find Cepheus, trace an imaginary line from the Plough’s pointers on past Polaris

    At an equal distance on the opposite side from the Plough is Cepheus, a circumpolar constellation and therefore visible no matter what the season or time of night. Face north in mid-April at around 22:00 to see Cepheus sit atop the Milky Way on a throne to the right of his queen Cassiopeia. The legs and seat of his throne make a rough square.

    On the Ursa Major side of Cassiopeia, it looks like a house (or throne) sitting on the Milky Way. The back of the seat comes to a point at the top above his head.

    As legend suggests, Cepheus is a fairly innocuous constellation and its brightest star, Alderamin, has a magnitude of only 2.4. The name seems to derive from medieval Arabic, Adh-Dhira' al-Yamin meaning ‘Right Forearm’. In about 5300 years’ time, because of precession, it will become the pole star, as it was around 18,000 B.C.

    It was in this constellation in 1784 that English astronomer John Goodricke first measured the regular variations in brightness of the star δ Cephei. His measurements were included in a report to the Royal Society and δ Cephei became the definitive Cepheid variable, in honour of Goodrickes work. Goodricke himself was something of a tragic figure. He was born a deaf-mute and died at the age of only 21 years, without ever seeing the importance of his work realised. Although in his paper to the Royal Society he had forecast that, "Such enquiries may probably lead to some better knowledge of the fixed stars, especially of their constitution and the cause of their remarkable changes."

    In the early years of the twentieth century Henrietta Leavitt established the relationship between the brightness of these stars and their period of variability. This period-luminosity relationship made it possible to find the distance to celestial objects as far away as the nearest galaxies.


    David J Thomas

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