Photo of the Week.Thin waning crescent just two days
Astronomy news for the week starting Friday, May 1, 2009.
Happy (as the week begins) May Day. We are halfway to astronomical
summer. And we also begin the week with the
Moon at its first quarter,
seen rising in the afternoon of Friday, May 1. The rest of the
week is now the province of the waxing
gibbous, which grows until the Moon hits full phase the night of Friday the 8th. Take
a look at the Moon as it passes south of Regulus in Leo the night of Saturday the 2nd, then the following
evening (Sunday the 3rd), when it will be seen several degrees to
the southwest of
turn/2009/12/">Saturn, formal conjunction taking place around
the time of moonset the following morning.
It's (sound the claxon) "inferior planets week." Having passed
greatest eastern elongation (against the Sun) last week, Mercury is briefly nicely visible
low in the west-northwest, early in the week not setting until
evening twilight glimmers to an end around 9:30 PM Daylight Time.
The evening of Saturday the 2nd finds the little planet in a very
pretty positioning just to the left of the Pleiades star cluster and well to the
right of the Hyades and orange
Aldebaran. You will need a
clear horizon and at least binoculars.
As Mercury is currently to the evening,
Venus is to the morning, only vastly more so. While it is not
easy to spot the former, the latter quite literally owns the dawn
sky, as the planet, rising just after 4 AM, reaches its greatest
brilliancy in its 2009 morning foray on Saturday the 2nd. At
magnitude -4.7, it is 20 times brighter than the brightest star, Sirius (which now lies well to the
southwest as the sky darkens).
In the middle of inferior planet action, we find the two giants of
the Solar System, Saturn and
Jupiter. Crossing the meridian
high to the south around 9:30 PM Daylight, Saturn does not set
until 3:30 AM, an hour after Jupiter rises. By the time Venus is
up, Jupiter has moved brightly into the southeastern sky. As
bright as it is, Venus tops it by a brightness factor of
One of the better meteor showers, the Eta Aquarids (the meteors seeming to radiate
from Eta Aquarii), arrives this
week, peaking the morning of Tuesday the 6th. Capable of up to 60
meteors an hour, the leavings of
Halley's Comet will be pretty much hidden by the bright Moon.