Hi Sky Friends,
It looks as though I am online now, in terms of the Journal Pioneer until it becomes hard copy again. Thanks COVID!! I will still be hard copy in our other local newspaper – the County Line Courier. Usually, I produce separate articles for each but August is the exception.
August is the month of the Perseid meteor shower, a prolific and wondrous display, but more of that to come.
Terms first:
Meteoroids – there are many “specks of dust” out in space and every so often during the night, our earth and its atmosphere “run into" some of these dust motes. They then tend to burn up in our atmosphere and we see these as streaks of light in the sky. We then call these meteors, or often more familiarly, shooting stars or falling stars. These may be a brief, short flit, or may last two or three seconds.
If the meteor does not burn completely up, and reaches the earth’s surface, we then call it a meteorite.
If the sky is clear, there will always be a few each night, but to “catch” them you have to be patient, and lucky.
Comets come from deep space in the outer solar system, for the most part. They are often called dirty or sooty snowballs. As they orbit into the inner solar system, and near the sun, they begin to metaphorically melt, and give off gas and dust in a long tail. The comet then goes back to deep space, but the dust remains, and over repetitive comet passes, a significant dust tail or trail develops.
If the earth and its atmosphere contact this dust trail during our yearly orbit around the sun, we will have an increased number of meteors, or shooting stars. We call this a meteor shower, or even rarely, a meteor storm. In a shower there are frequently 10-25 meteors per hour(ho hum!) but occasionally, the count may approach 80 or even 100 per hour. Now that begins to get exciting! In a storm, a rare event, the counts increase dramatically. In the 1830’s, there was a meteor storm, watched over London, England, with perhaps 300,000 per hour. In 1966, a professional astronomer in California estimated watching 20,000 per hour. I cannot begin to imagine what that would be like.
Now, occasionally, there will be a very bright meteor, lasting several seconds as it crosses the whole sky and it can even leave a brief contrail, like a jet plane. It is said that rarely you can hear a rumble as of low thunder (I never have). You can even see a Bolide or meteor breaking up into pieces as it crosses the sky. Very bright ones are also called fireballs. Meteor showers can last principally one night, or at lower counts, even up to two weeks.
So – the Perseids. This year this meteor shower should be best the night of Aug. 12 into the morning of Aug. 13. It is usually best to watch a meteor shower after midnight when the shower is at its prolific best. This year may be the exception because the moon, which is always the great spoiler of meteor showers will rise between midnight and 1 a.m. However, because of the old moon phase, it will only be one-tenth as bright as the full moon and will let us still see many meteors.
I am often asked where to look, and the answer is: anywhere, because they can be seen all over the sky, although in a shower they arise from a common point.
How to watch?
First with friends, and have fun. Come to where you watch, at least prepared to dress warmly, as it can get cool and damp. If you are out where you won’t bother people by noise, have a radio.
Make sure you have a thermos of a hot drink.
Perhaps most importantly, make sure other know where you are. Then have a grand time, and every time you see one, don’t be afraid to yell “I see one” (unless you are by yourself of course).
In the sky this month
So, what is in the sky this month. It’s a grand night(s) for planets as Jupiter and Saturn are really putting on a show.
We say a planet is at opposition when it is directly opposite in the sky from the sun. Another way to understand this is that it is the time in earth’s orbit when the earth passes directly between the sun and the planet.
Jupiter is at opposition Aug. 14, and Saturn on Aug. 21. At opposition, a planet is at its nearest to us, and thus usually brightest. It will essentially rise at sunset and set at sunrise on that night.
Through the month of August, medium high in our southern sky, Jupiter is the brightest object there with Saturn several degrees to its left. Jupiter is 14 times brighter than Saturn but Saturn is still a very easy object to see, as bright as a bright star. At the same time, a really “neat” digression – look to the right and a little down from Jupiter and you should be able to see a group of stars that looks like “The Teapot”.
Mars is an evening planet rising in the east by mid to late evening but extending into the morning hours high in the sky. It is dimmer than the two above but is brightening, and by October, will out shine Jupiter.
Venus will be in the predawn sky, along with Mars rising in the east, and indeed is the third-brightest object in the sky after the sun and moon.
If we look east-northeast in the morning twilight, 30-45 minutes begore the sun rises, we will find Mercury for most of this month, low in the sky.
If you find the teapot I described above, you might really want to stretch your abilities. Look to the right of the teapot and you may be able to visualize a scorpion with its stinger — great catch!
- New Moon - August 6th
- Full Moon - August 22nd
Well that is another month. Hope to see you in the Journal Pioneer – hard copy soon.
See you next month.
Dr. Rolly Chiasson is your night sky guy. His column runs monthly. To comment or get in touch with him email [email protected].