The Night Sky

This week is a good time to spot a very elusive planet Mercury. Little Mercury is the closest planet orbiting our sun and just as the speedy messenger of its namesake it races around our home star in just 88 days.

Mercury and Venus are what we call inferior planets meaning they orbit our sun inside the orbit of our own planet. Because of that we can only see them just before sunrise or just after sunset when they are out to either side of the sun in their orbits. Mercury because of its smaller orbit never strays far from the sun while Venus with its larger orbit will sometimes hang for hours before the sun rises or after it sets.

This week Mercury has reached its greatest elongation from our sun on Sunday and so hangs low in the western sky after sunset. Find a clear view to the western horizon about a half hour after sunset and raise your fist at arm’s length. Scan the sky for a small steady shining dot just above your fist. Binoculars will greatly help but it should show easily to the unaided eye. It will set quickly just before 11 p.m.

Jupiter and Saturn both shine all night starting in the east and drifting towards the west with the stars. Venus still shines in the morning slowly moving closer to the sun and Mars is still visible in the west after sunset as a small reddish star.

The Haliburton Forest Astronomy program begins June 28 and runs weekly on Friday nights throughout the summer. For more information visit or call 1-800-631-2198.

Brian Mould

Haliburton Forest Observatory