may2009nightskiesovertanzania

May Night Skies over Tanzania

By Dr. N. T. Jiwaji, ntjiwaji AT yahoo.com

After a very eventful 100 Hours of Astronomy event of the International Year of Astronomy in early April, and its success in involving the public all over the world, another world wide event is planned for 23-24 October 2009. It will be conducted under the title “Galilean Nights” in honour of Galileo who was the first to point a telescope at the heavens and started a revolution in scientific thinking. This event will give us another chance to take astronomy to the public and to attract interest in science and to make a larger impact on increasing the awareness of the importance of fundamental science in Tanzania.

May skies have remained relatively clear in spite of the rainy season. In fact because of the occasional rains the sky is washed clear of any dust leaving the sky sparking dark with much reduced light pollution in urban areas. Light pollution occurs when dust suspended in the skies scatters (redirects) the light back to the surface and hence the sky becomes too bright to observe fainter stars. If you get a clear night or with few clouds, use the opportunity – this is time to enjoy the stars.

However, the best view of the skies is from above the atmosphere. The famous Hubble Space Telescope was launched into orbit in 1990 after 7 years of staying in a store due to the grounding of all Space Shuttle missions after the Challenger disaster. Hubble has broken records after records in the images it has captured, especially since it captures pictures in true colours that we can see. It has been maintained regularly, with each mission increasing its capabilities, but during this mid-June overhaul it is undergoing major renovations that will increase its useful life until 2014.

During this repair mission of the Hubble Space Telescope there was a chance of the astronauts being hit by fragments from space wreckage caused by recent collisions of Russian and American space crafts and remnants of a Chinese space craft destroyed by a missile from the ground as a test by the Chinese. In fact a second space shuttle was kept ready in standby to be flown a rescue mission in case there was any space disaster that put the astronauts in danger.

Saturn is high in the sky still hugging close to the feet of Leo constellation. It shines with a sharply piercing light which you can distinguish only by closely watching it. While other stars’ pin-point size makes them twinkle due to atmospheric effects, the Saturn’s disc allows us to see it as a steady point. New Moon is on 24^th and soon after quarter phase, a half Moon will be close to Saturn on 31^st May.

Jupiter is beginning its residence in the evening skies but this month it still rises close to midnight. The next months will allow more comfortable viewing. The other visible planets are in the morning sky. Most interesting is the period from 19^th to 23^rd May when the Moon, Jupiter, Venus and Mars form an apparent line with the rising sun. This line is called the ecliptic along which you will see the solar system bodies since they are rotating in a flat plane.

In the night skies this month, the most recognizable constellation Orion bids us farewell and sets by 8 p.m. Leo, with an inverted question mark forming the head of the lion, and its lounging body dominates the overhead skies, though the full glory of this constellation can easily be obscured by city lights.

The Pointers, the Southern Cross in the southern sky and the Big Dipper in the northern sky, are well positioned from early evening and are high in the sky so they can be used to locate south and north directions (see map). Scorpio pops its front claws early in the evening and by 10 p.m. the sweeping, curving tail with the sting at its end formed by a close pair of stars easily made out.

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