The planet Venus has erupted into view in the eastern
morning sky during the past couple of weeks.
When September opened, this resplendent Morning Star was
rising just after dawn's first glow at around 5 a.m. local daylight time. But
with each passing morning, Venus has been rising ever higher and has been
getting a little brighter.
It will attain its greatest brilliance on Sept. 23,
appearing at an eye-popping magnitude of -4.6. This is 19 times as bright as
the brightest
star in the sky, Sirius (in Canis Major, the Big Dog), and 10 times as
bright as the next-brightest planet, Jupiter. (On this astronomers' scale,
smaller numbers represent brighter objects, with negative numbers reserved for
the brightest of all.)
See it during the day
Try looking for Venus through the brilliance of the daytime
sky. It can be done if you know exactly where to look. Those who live in rural
areas far from any extraneous light have reported that Venus can cast a faint,
yet distinct shadow.
Probably the best method is to simply keep it in view until
after the sun comes up. At its current extreme brightness, it can often be
perceived as a tiny white speck against the blue backdrop of daylight.
And by month's end, it's rising at around 3:30 a.m. and will
precede the sun by some three and a half hours.
Venus was at inferior
conjunction on Aug. 18, in line between the Earth and the sun. Now it is
swinging away from that line, speeding ahead of the Earth in its faster orbit. So
in a telescope
during September, it displays a large, brilliant, beautiful crescent that waxes
in phase all month while shrinking in size.
When September opened,
Venus was only 8-percent illuminated, but by month's end, that figure will have
increased to 33 percent. But because it will have receded 16 million miles from
Earth, the planet will appear more than one-third smaller than it did at the
start of the month.
Magical telescopes
Thoughts of viewing the
crescent of Venus reminds me of an amusing story related by George Lovi (1939-1993),
a well-known astronomy lecturer and author who was also a good friend of mine.
One night, while running
a public night at the Brooklyn College Observatory in New York, the telescope was pointed right at Venus
which was then displaying its delicate crescent shape. Yet one student gazing
through the telescope eyepiece stubbornly insisted he was not looking at Venus,
but at the moon instead. When George commented that the moon wasn't even in the
sky, the student replied, "So what? Doesn't a telescope show you things you
can't see without it?"
During the coming weeks, Venus will also be floating ever closer
to the bright star, Regulus and the planet Saturn, its evening partners from July.
By the end of this month, Venus and Regulus will be separated by about 7 degrees
and Venus and Saturn by 10 degrees (your clenched fist held at arm's length measures
roughly ten degrees in width).
Come early in October, this trio and a lovely crescent moon
will make for some eye-catching configurations in our predawn sky.