Shop at Amazon US

Contributions

If you like the website and want to contribute to the running costs then please do so below. All contributions are most welcome.

PayPal - The safer, easier way to pay online.

Mercury starts November on the eastern side of the Sun and for the early part of the month is visible in the evening twilight for observer's located at equatorial and southern hemisphere latitudes. After passing through inferior conjunction on November 17th, Mercury then moves out to the west of the Sun before reappearing in the morning sky during the last week of November.

The planet should then be visible as a morning star for much of the remainder of the year. On November 25th, for observers located at 51.5N (e.g. London, England), Mercury is located a little over 6 degrees above the southeastern horizon, 45 minutes before sunrise. The altitude of Mercury then increases each morning until it peaks at nearly 10 degrees on December 4th, the date of greatest elongation west. On this date, Mercury is 21 degrees west of the Sun. The planet then moves back towards the Sun appearing a little lower each morning until about the last week of December, when it becomes lost to the bright twilight glare.

Due to the angle of the ecliptic, the visibility of Mercury this time is not quite so good from southern hemisphere locations. For example, from Sydney, Australia (34S), Mercury is less than 2 degrees above the horizon, 30 minutes before sunrise on November 25th. It then rises to about 7 degrees around December 10th before gradually creeping back down. As with northern hemisphere observers, the planet will be lost to the bright glare of the Sun before the end of December.

Also visible in the morning sky are the planets Venus and Saturn. The relative positions of the three planets, along with magnitude 1.0 star Spica are shown below. From November 25th to December 30th, Mercury's magnitude increases from 0.9 to -0.5. Venus of course is much brighter at about magnitude -3.9, while Saturn shines at magnitude 0.8.

Mercury, Venus, Saturn, Spica and the Moon - NH - November and December 2012

Mercury, Venus, Saturn, Spica and the Moon - SH - November and December 2012

The morning of December 5th is a good opportunity to spot the three planets and Spica as they will appear almost in line. On this day, Mercury is relatively bright at mag -0.4, Venus brilliant at -3.9, Saturn at magnitude 0.8 and Spica at magnitude 1.0.

Mercury, Venus, Saturn, Spica as seen from London on December 5, 2012

Mercury, Venus, Saturn, Spica as seen from Sydney on December 5, 2012