May 2012 Night Skies over Tanzania

Venus, the evening star that has been adorning our western sky since October last year, now appears lower each day close to the horizon at sunset. By the end of the month, it will dip below the horizon, getting ready for a remarkable event, called the “Transit of Venus” on June 6 when it will pass directly in front of the Sun.

On June 6, Venus will be exactly in line and between the Earth and the Sun, so the event can be likened to an eclipse. During a normal solar eclipse, the Moon is able to cover up the face of the Sun since the Moon is close to us. However, during the Transit of Venus, the planet, which is very far away, will not be able to cover up the whole face of the Sun. It will appear as a tiny dot sliding slowly across the face of the Sun.

While the sun rises on June 6 in Tanzania, from 6:34 am, up to 7:49 am we will witness the end of the Transit as Venus slides out of edge of the Sun. You will need eclipse glasses to shut out the Sun’s dangerous glare to see the tiny dot of Venus crossing out of the Sun’s top right edge, as the transit ends.

The June 6 transit is the second in the pair of transits of Venus. The last one took place in 2004. Though the pairs are separated by a few years, each pair takes place after more than a century. Therefore, the next transit will take place after 105 years, in 2117. Prepare yourself not to miss this lifetime opportunity to view tiny Venus trying to “eclipse” the mighty Sun. For updates and details of the event, visit www.AstronomyInTanzania.or.tz.

Two other more familiar eclipses events precede this transit of Venus. One is a major world event of an Annular Solar Eclipse that will take place on May 20, mainly over the Pacific Ocean. The other is a Partial Lunar Eclipse on June 4 that will also take place over the Pacific. Therefore, we will not be able to see both these eclipses. However, you can follow them on the Internet.

The other planets that are visible in the night sky are the spectacular Saturn that is visible in the eastern skies, and red Mars overhead. Saturn is the most beautiful to catch in a telescope because of its remarkable flat system of rings. Mars is distinct as a reddish star, but it is now too far away to see any features on its surface using a telescope.

New Moon is on May 21, while Full Moon will be on June 4 both are dates when eclipses will be occurring on the other side of the world. This is not a coincidence. Solar eclipses can only occur at New Moon when the Moon is between the Sun and our Earth. Similarly, lunar eclipses will occur only at Full Moon since the Moon is directly opposite the Sun from Earth.

The Moon will be closest to Mars on May 28 and 29, while it will be close to Saturn and nearby star Spica on May 31 and June 1. Use these dates as markers to seek out Mars and Saturn in the skies. Mars is also recognized by its reddish coloured glow. Another way of distinguishing planets is by their light, which does not twinkle, while stars will be seen to twinkle distinctly.

We will see the last of the most recognizable Orion constellation this month, so go out and behold it lying low in the west, close to Taurus with its twinkling Pleiades cluster also called the ‘seven little sisters’. However, Gemini, Leo, and Cannis Major with its brightest star in the sky, Sirius, are easy to recognize in the mid skies. Towards the east, Virgo and Boots can be recognized by their brightest stars Spica and Arcturus, respectively while another constellation that is easy to recognize, Scorpio rises in the east. The south and north directions are also well marked by the southern cross and the big dipper whose stars are used to point out these directions.

Mar is close to the feet of Leo near its brightest star Regulus, while Saturn in close the brightest star, Spica, in Virgo.

The International Space Station can best be seen on June 6 when it will be extremely bright while crossing right across the middle of the sky, passing close to Mars in overhead sky. It will rise above the southwest horizon at about 6:39 pm and will cut through the middle of the sky, rising to 80 degrees, after which will it will cruise lower and will disappear lower in the northeast sky at 6:46 pm.

Another bright satellite that you can easily follow is the Tiangong 1 satellite which is the starting module on which China’s space station will be built. It is big enough to be bright when it passes overhead after sunset. This month it can be seen on May 27 from 7:07 pm when it will rise from the southwest horizon and cut through the middle of the sky towards the northeast. Before it reaches the other horizon, it will enter the earth’s shadow and disappear at 7:12 pm.

More details about viewing of ISS and other satellites and exact timings can be found at www.heavens-above.com and entering your location.

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