Once again, the days are getting shorter, but that means we can enjoy the night sky earlier!
The Perseid Meteor Shower: media hype vs realistic expectations
The Perseid meteor shower is so named because the meteors seem to originate
around the constellation Perseus, which is low in the NE in the evening.
As a reminder, a “meteor shower” occurs when Earth passes through the
trail of dust left by a passing comet, in this case Swift-Tuttle in 1992.
The tails of comets are composed of gas and dust that is released from
the comet as it interacts with the Sun’s solar wind. The dust follows
more or less the original path of the comet, spreading out somewhat with time
and continuing to fall slowly towards the Sun, so every year we pass through
that trail of dust around the same date. The dust trail can last hundreds
of years. A meteor, then, is simply a small speck of that dust burning up
as it passes into Earth’s atmosphere at extremely high speed.
The annual Perseid meteor shower peaks the evening of Monday, August 12, and
you can expect fair activity the day before and the day after. There may be
some lesser activity a few days either side of that, but it will be less than
half the maximum of the peak.
Unfortunately, news sites want to excite you and keep you on their pages.
To do so means overstating things. Their comment that you could see
up to 100 meteors per hour is under absolute ideal conditions, which almost
never occur, in particular since an almost full Moon will be lighting the sky
this year, limiting you to seeing only the few brightest meteors. As an
aside, in all my life, only during one spectacular night did I ever see 100
meteors an hour.
All that said, it is still worthwhile to have a look. To enjoy the
Perseids, find as large a patch of open sky as you can, away from house lights
or streetlights. Lay back on a blanket or lounger, and just watch the sky
with your naked eyes, preferably looking away from the Moon. Give your
eyes a few minutes to adapt to the slightly darker night sky.
The Moon and Planets
A crescent Moon is now visible in the west southwest before and after sunset.
On Friday, August 9, a gibbous Moon - that is one that is more than half
lighted - will be just to the upper left of bright Jupiter. You can’t
mistake Jupiter, as it is the brightest star-like object in that part of the
Saturn is not very bright right now, but you can pick it out on Sunday, August
11, when it will be just to the upper left of an almost full Moon. It
will be brighter than the stars around it, so you should be able to identify
If you are up just before 6 a.m. and have a clear horizon to the east, you may
see Mercury very low in the sky - again, it will be brighter than other stars
in the area. It will be easiest to see within the next week or so.