Jupiter (Upper right) and Mercury (Lower left)
I had a clear western sky last night at 18:45 / 6.45pm that I see Mercury (on the right) has moved upper to close Jupiter that  it has showed to compare I saw last Monday 14th. (See photo of Monday 14th.)

Hopefully tonight after 18:00 / 6pm I will look west for Mercury passing above Jupiter at twilight sky.

The image showed below that you could find it tonight.

Jupiter (Upper left) and Mercury (Lower right)
The image was captured by Derek Rowley, Milton Keynes, UK at 18:30 / 6.30pm.

Mercury passes Jupiter in bright twilight around March 15th.

Mercury
This month (March 2011) is your best chance to spot Mercury all year, because Mercury reaches the highest sky and longest evening apparition.

Plus the best this week
Mercury in the evening  west to spend the week from Saturday 12th March 2011  to Friday 18th March 2011 within 5 degrees of Jupiter, and better to use a binocular to overlook Mercury alone, the pairing is absolutely unmistakable.

Thanks, Sky & Telescope for animation
Find a spot with a clear, open view low to the west, and you can watch Mercury passing Jupiter in twilight from March 13 to 16. Click here for a Sky & Telescope’s  animation!

Sunset Planets
Mars and Saturn are meeting at a particular place with Venus to form a skinny triangle in the sunset sky in the West. When the sun sets tonight, go outside and look West.

Venus pops out of the twilight first, followed by Saturn, then Mars by binoculars or a small telescope.

See the SkyMap for tonight (Monday 26th July 2010), also Friday 30th July 2010 and Saturday 31st July 2010 when Saturn and Mars are only 2^o apart.

Transit of Mercury
Occasionally, Mercury can seen acrossing the Sun known as “Transit of Mercury” (movie) – the last time, it was happened on 7th  November 2003, before that it was 15th November 1999 but it was not visible from the United Kingdom, back to 10th November 1973 for the last Mercury transit visible from these parts. (I was five years old, no-body told me! )

Looking forward to the next transit was in November 2006 but again – we were not right place at the right time, then we have to wait for next 13 years since 2006 until May 2016 to see our next Transit of Mercury from the United Kingdom.

Transits of Mercury can happen in May or November.  November transits occur at intervals of 7, 13, or 33 years ; May transits only occur at intervals of 13 or 33 years. The last three transits occurred in 1999, 2003 and 2006  -  the next one will be in 2016, but not this year! – you can wait five more years!

In 2003, I had seen the “Transit of Mercury”, where I was with Milton Keynes Deaf Astronomical Society  with other members.
(See the VideoClip).

Mercury is at its greatest distance east from the Sun this evening, so you will see every evenings that Mercury is sloping low, lower and lowest meanwhile Venus is rising high, higher, and highest.

Click here for enlarge image.

Catch Mercury close to Venus in twilight in the western.

See the SkyMap.
See my archive :-  Friday 26th March 2010.

Facts
Mercury is the smallest of the four inner planets (Mars, Earth, Venus and Mercury) and difficult to observe because it is never more than 28 degrees from the Sun, and small angular diameter at greatest elongation but  it would be easily to be spot them tonight by naked eye or binoculars, and through by a small telescope for Mercury’s phases ~ 60% sunlit.

Click here for enlarge image.

Mercury
The closest planet to the Sun, does re-appearance in the evening skies very low in the west during the last week of March that you may just catch a glimpse of Venus and Mercury  before it sets on the horizon by a naked eye.

Both planets are the best to be seen, at altitude, 9 degrees on March 31st at 20:00 / 8pm (BST) in the constellation of Pisces (The Fishes).

Mercury is at greatest western elongation from the Sun.

See the diagram:- greatest western elongation.

Mercury is in the constellation of  Sagittarius (The Archer), visible in the eastern sky before sunrise.