Jupiter shines extremely brightly together with the brightest star Sirius shines in the sky in the overhead in the night skies, while the second brightest star Canopus shines nearer the south.  However, the limelight is taken this month by Mars and Mercury which show movement in the skies.


Mars is nearing opposition on May 22 when it will be in a straight line alignment with Sun and Earth in between. At opposition the full face of the planet is lit by the Sun which is behind us at night.  At this time the planet rises at sunset and sets at sunrise with overhead position at midnight.  Mara is also currently moving closer to Earth and will be closest to Earth on 30 May at 75 million kilometers so its angular size is biggest while its full face is lit by the Sun, hence Mars can be easily spotted as a bright red dot in the night.  Currently it is rising in the East at 8 pm positioned inside the mouth of Scorpio near its red star Antares and nearby extremely bright Jupiter.  You can differentiate between the two red objects by the way the star Antares twinkles while Mars shines with a steady light.  At opposition on May 22 it will rise at sunset just outside the Scorpio’s mouth well and noticeably away from the red Antares and Jupiter.   It has not been closest since 2003 and will not be seen as brightly until the next opposition in 2018.



Furthermore, Mars is undergoing retrograde (opposite) motion in the sky.  All celestial objects move from west to east as they shift day after day across the background stars.  You will have noticed that the Moon shifts day by day from West at new moon phase until it reaches full moon phase in the East after 15 days.  Currently Mars can be seen inside the mouth of Scorpio near the red star Antares and brilliant Jupiter.  By May 22 you will notice that its position will have shifted westwards in retrograde motion to outside Scorpio’s mouth and will continue to do so until it is well away from Scorpio by the end of June.  It will end its retrograde westward movement on June 29 and will then move eastwards resuming its normal movement into the mouth of Scorpio, past red Antares and brilliant Jupiter and further eastwards until the next cycle which will be in 2018.


Mercury will make its appearance during the day on May 9 when it will cross the face of the Sun from 2 pm to sunset.  This called a transit which occurs when an inner planet Mercury or Venus are exactly aligned in a straight line with the planet between the Sun and Earth.  Usually there is always a slight angle between the three objects hence transits do not occur frequently.  This is similar to what happens during a solar eclipse when the Moon comes between the Sun and Earth. Again this does not happen every month since there is a slight misalignment of the three object.



The last transit of Mercury was in November 2006 while the next Mercury transit will be in November 2019.  Venus last transited the Sun in June 2012 and the next Venus transit will not occur until after more than a century in 2117.  Historically transits were used to determine the distance from the Sun to Earth by observing the transit simultaneously from different latitude positions.  The paths the planet across the face of the Sun will be different at different latitudes and from this the distance from Sun to Earth can be determined. 



Transits can be seen by projecting the image of the Sun through a telescope or a pinhole onto a white screen that has been shaded from surrounding light so that you can make out the tiny dot as it crosses the image of the face of the Sun.  IT IS DANGEROUS TO LOOK AT THE SUN DIRECTLY. You can time the moments of first contact of Mercury with the Sun on May 9 expected at 14:12:11, as well as the path of Mercury across the Sun and share your measurements with other enthusiasts on the internet and combine those measurements to get your own determination of the distance of Sun from Earth.


You should also prepare yourself for the major event of the Annular Solar Eclipse that will occur on September 1 this year, centered over southern Tanzania and visible across the whole of Tanzania with more than 90 percent of the Sun covered.  It will also be visible across almost the entire African continent with coverage decreasing towards north and south of Africa.  The central path of the eclipse will cross southern Tanzania from Katavi to Mbeya to Ruvuma and in an approximately 100 kilometer-wide path the Sun will be covered by the Moon such that it will leave a thin bright ring around the edge of the Sun for about three minutes.  The rest of Tanzania will witness more than 90 percent of the Sun being covered and will see a thin crescent shape of the Sun.  The whole eclipse event from beginning to end will last from 10 am to 2 pm.  You will need to use solar viewers to view the eclipse safely.  People from across the country and across the world will be coming to Rujewa, about 100 km from Mbeya, is most ideally located to be within the central path of the eclipse where a ring can be seen and the weather is expected to be clear to provide good viewing conditions. Scientists will set up equipment to observe the eclipse and its effects on the atmosphere and the surrounding.  Do not miss this opportunity to see this unique event in Tanzania.




Among the constellations to look out for are the Southern Cross in the south, whose long diagonal points towards the South.  Nearby the Southern Cross are the pair of pointers that point towards the Southern Cross.  The lower star of the pair is Alpha Centauri, the nearest star to us though its light takes four years to reach us.  Scientists are now attempting to shoot micro-spacecrafts towards this star hoping to make contact with other life that may be living in planets that revolve around that star.


Other constellations of interest is the Big Dipper with the shape of a frying pan whose side stars point towards the north direction.  Among the recognizable zodiacal constellations that run from west to east are Gemini, Leo, Virgo and Scorpio. The Milky Way contains a thick collection of stars and interstellar dust is seen towards the south from south west horizon to south east and contains the Cannis Major constellation which has the brightest star Sirius. Other constellations within the Milky Way are the Southern Cross, Scorpio and Saggitarius which is the direction towards the center of our Milky Way galaxy.