Overall, the May evening sky marks a transition. Brilliant winter stars (including Sirius) are leaving the evening sky, while the stars of summer are only beginning to peek over the eastern horizon.
At dusk this month, the plane of the Milky Way roughly coincides with the horizon. We are therefore looking up out of the Milky Way plane, where there are fewer bright stars. One bright star high in the sky tonight is Arcturus, which you can find by extending the arc of the Big Dipper’s handle (‘arc to Arcturus’).
Arcturus, the fourth brightest star we see at night, will be the brightest star left once we can no longer see Sirius. The Big Dipper happens to be at its highest above the North Star at dusk this month.Mercury makes a brief appearance in the evening sky this month. Look for it in the west at dusk, right over the point of sunset.
Mars continues to fade as Earth pulls away from it. To see Mars, look high in the sky to the west at dusk to the upper left of the ‘twin’ stars of Gemini. Mars’ position among the stars changes quite noticeably on a nightly basis.
Saturn is high in the sky towards the south at dusk this month. Look to the south at dusk, almost overhead, to find stars in the shape of a backwards question mark. These form the mane of Leo, the lion. The ‘point’ under the question mark is Regulus, a star of similar brightness. Saturn is to Regulus’ left.
Jupiter is in the predawn sky this month, located in the south at dawn. It outshines everything else there unless the Moon is present.
Venus is lost in the Sun’s glare, and will remain out of sight through the end of the summer.
When do the Dog Days of Summer begin? Find out for yourself by noting when the last day in May is that you can still see Sirius, the Dog Star. As May opens, Sirius is easy to find; it outshines all other stars we see at night and is the brightest thing in the southwest at dusk. However, Sirius appears lower and lower to the horizon each night this month. As May comes to a close, Sirius sets deeper and deeper in twilight and finally becomes invisible by month’s end. Ancient Egyptians believed that Sirius, as the brightest star in the night sky, would reinforce the Sun’s heat if it were up during the daytime. Thus, the time of year when Sirius is not visible at night (and therefore up only in daytime) became known as the ‘Dog Days’.
Moon Phases in May 2008:
|New||May 5, 7:18 am|
|1st Quarter||May 11, 10:46 pm|
|Full||May 19, 9:11 pm|
|Last Quarter||May 27, 9:57 pm|
For the best viewing conditions, get as far away from the city as you can – and visit us again to let us know what you see.