Photo of the Week.
Pleiades and company, the famed
"Seven Sisters" seen diving down the western sky.
Astronomy news for the week starting Friday, April 20, 2012.
We begin our week with the Moon in its
new phase, which is passed the night of Friday, April 20. During
the remainder of the week, we then see our companion as a growing,
waxing crescent, as it heads toward first quarter the morning of Saturday the
29th. See if you can spot the thinnest crescent in twilight the
evening of Sunday the 22nd. It shines just above Jupiter, which is being lost from sight, the
two requiring good timing and a very flat horizon.
The crescent then launches itself upward, each night climbing
higher. The evening of Monday the 23rd, find it positioned just to
the left of the Pleiades of Taurus, down below Venus.
The following night is better, when the Moon nicely paired with the
brilliant planet, appearing down and to the left of it and just
above the Hyades and Aldebaran. The Moon then leaves
the scene, falling well up and to the left of Venus the night of
Wednesday the 25th. The following evenings the Moon then takes on
Gemini to the south of Castor and Pollux until it hits dim Cancer at
first quarter. On Sunday the 22nd, just past new, the Moon goes
through apogee, where it
is farthest from Earth, the slightly increased distance notably
weakening "spring" tides at the coasts.
Venus still dominates the early evening sky, the planet just shy of
its greatest possible brilliance. Now quite far to the north of
the celestial equator, Venus sets
around 11:30 PM Daylight Time well toward the northwest, Jupiter
preceding it by more than two hours. We still, however, have time
to admire bright Mars, which crosses the meridian to the south just as twilight
ends. Still hanging out to the east of Regulus in Leo, the red planet is up until 4 AM. The night,
though, really belongs to
Saturn, which is already up at sunset, transits the meridian
just before midnight, and is visible all night to the northeast of
Spica in Virgo. In invisible news, Mercury is in
conjunction with Uranus on
Saturday the 21st.
The nights of Friday the 20th and Saturday the 21st (actually the
following mornings) are marked by the annual Lyrid meteor
shower, which typically produces about a dozen meteors per hour
coming from the direction of the constellation Lyra, the Harp. They appear to be
related to Great
Comet of 1861.
The early evening sky is the time to view Leo, which rides high around 9 PM. Between it and Gemini to the west find dim Cancer, the Crab, and to the southeast
look to Virgo and Spica. To the north of the Lion rides the icon
of spring skies, the Big Dipper
of Ursa Major. Follow its two
front bowl stars to the north to see Polaris, about which the sky appears to turn.