Photo of the Week. A near-perfect third-quarter Moon
rises facing east toward the illuminating Sun.
Astronomy news for the week starting Friday, November 2, 2007.
Comet
Holmes still amazes with its extraordinary outburst. See
it as a bright third magnitude starlike object in Perseus just to the east of the constellation's Perseus's brightest
star, Mirfak (Alpha Persei).
Through the telescope, it's a starlike object surrounded by large
circular coma from which projects a short, foreshortened tail.
Moving slowly west against the background stars, no
one knows how it will behave. We are closest to the comet, 1.6
Astronomical Units (Earth-Sun distances), on Tuesday the 6th.
The Moon spends the entire week in its waning crescent phase, when it is visible
in the morning hours. It does not pass new until Friday, November
9. What it will do, on the morning of Saturday, November 3,
is to
occult, or cover, the first magnitude star Regulus in Leo, at least if you live in the southern or
southwestern part of the US below a line that runs from the
southern tip of South Carolina to the southern border of Oregon
with California. Times of Regulus's disappearance behind the Moon
vary with latitude and longitude. In the middle of the country, it
takes place around 6 AM Central Daylight Time. Reappearance is
anywhere from a few minutes (for northern regions) to an hour
later. The best place to watch is the northern "graze line," where
the star can be seen winking in and out between lunar mountains and
crater walls. In the northern part of the country, the star will
appear just to the north of the Moon. From wherever you see it, Saturn
will appear down and to the left.
Then don't forget that the US returns to Standard
Time the morning of Sunday, November 4.
The rest of the week sees the waning crescent plunging to the east
through southern Leo and then through Virgo. The morning of Sunday the 4th the Moon will
appear below Saturn. Then look for a fine conjunction with brilliant Venus,
which will lie very close to the crescent the morning of Monday the
5th, the planet appearing to the left of the Moon in a classic
pairing. The last glimpse of the thin crescent will be on the
morning of Wednesday the 7th, when the Moon will appear above and
to the right of Spica and Mercury.
That wonderfully bright "star" in the east is indeed Venus, and it
lingers for us, rising shortly before 3 AM Standard Time.
Separating itself ever farther from Venus, Saturn (still
beautifully placed to the east of Regulus) now rises around 1 AM.
Switching to the evening sky, Jupiter is rapidly disappearing, setting only half an
hour after the end of twilight. But don't despair, as Mars rises in
Gemini only an hour and a half
after Jupiter sets, around 8:30 PM. The red planet then crosses
the meridian to the south an hour
before dawn commences. Finally, morning's Mercury makes a bit of a
splash as it passes greatest western elongation with the Sun (just
19 degrees to the west) on Thursday the 8th, rising at the
beginning of twilight.
Any meteors you might see may be coming from the northern or
southern Taurids
(as they seem to emanate from Taurus), weak streams that produce around 5 slow
meteors per hour and are the debris of Comet Encke,
which has the shortest period of any known comet, just a bit over
three years.
