Don’t despair! The days are growing shorter daily with more hours
of darkness. But in perfect balance we are in the midst of long evenings
of sunshine and warm weather. That’s the Yin and the Yang of Canadian
summer nights. Celebrate that balance and enjoy everything nature has to offer.
Like comets, asteroids travel through the universe and are visible from Earth periodically or sometimes are visible only once in a lifetime because their orbits are too vast.
Asteroids differ from comets in that they are made of rock while comets have been described as “dirty snowballs.” They often have a rock core encompassed by layers of ice containing rocks.
This month’s asteroid is called Ceres and it will be passing through the constellation Ophiuchus the Serpent Holder. You can locate it in the northern summer sky on the opposite side from the constellation Orion the Hunter. Orion is a popular shape in the night sky and many people can locate that stick-figure shape containing three belt stars.
Woohoo! We have a comet in the neighbourhood. But you will require a telescope to see it when it visually peaks at 8th magnitude. In English that means the comet is too faint to be seen without visual aid such as a telescope.
Under pristine dark sky conditions, the limit of naked eye seeing is in the 6th magnitude range. But at a star party I attended a few years ago, a lady from Manitoba spotted a 7th magnitude star with her naked eye.
By the way, a “star party” is an event where astronomers camp out in a dark site and stay up all night observing. The events usually include speakers on various topics, door prizes, telescope judging, astrophotography contests, binocular sky walks, and lots of recreational activities. Last year at the Saskatchewan Summer Star Party there was an exhibit of celestial-themed quilts. From a comet to a quilt!
(where and when to find them)
Evening (west): Mercury, Venus, Mars & Saturn (all visible with the naked eye)
Midnight: (east): Jupiter (visible with the naked eye) and Uranus (need visual aid)
Morning: (south): Jupiter (visible with the naked eye) and Uranus (need visual aid)
July 3: This conjunction or close pairing of two celestial objects is perfect for early risers. About 90 minutes before sunrise, since you’re already awake and keen for an observing opportunity, locate the moon with the nearby bright planet Jupiter approximately 7 degrees to the lower left of the moon.
Seven degrees is estimated by holding your closed fist at arm’s length and sighting past it with one eye. Seven degrees would represent the width of 70 per cent of your fist. It’s just an estimate since everyone has different-size hands. But there will be no mistaking the bright planet Jupiter. Note that Jupiter is also obvious because it glows but does not twinkle. Remember: stars twinkle but planets do not. All this time, Jupiter is spending time within the constellation Pisces the Fish. So if you’re looking at Jupiter right now, you are also looking at the constellation Pisces.
For those early risers owning binoculars, locate Jupiter and you may be able to see the much fainter planet Uranus only 2 degrees to the right of Jupiter. Two degrees is the width of two fingers held at arm’s length. If you are able to detect colour, Uranus has always looked blue-green to my eye.
Before I move on, here are some final considerations about measurement in the night sky. A fingertip at arm’s length covers approximately 1 degree. Both the sun and moon are each one half degree wide. NEVER LOOK AT THE SUN. But do look at the moon. Holding out your thumb at arm’s length, one can easily cover the moon. Try this when the moon is rising from the horizon and appears huge and try it again when the moon is riding high in the sky. You thumb will easily cover both objects even though they seem disproportionate. And the Big Dipper is 25 degrees across. Finally looking from the horizon to the point straight overhead (the zenith) is 90 degrees.
July 14: Looking west toward west-northwest(WNW) about 40 minutes after sunset, locate the waxing crescent moon along with the very bright planet Venus about 7 degrees to the moon’s upper right. Your eye will be looking pretty close to the western horizon with Venus being about 10 degrees above it. Here’s another observing opportunity: Venus is bright and obvious but tiny, star-like Mercury is sitting not far above the WNW horizon and resembles a star but not a twinkling star. That’s one way to identify it. Starting at Venus, look down toward the right at a 45 degree angle and visually continue in a line until you spot Mercury. Back to Venus.
Try the same visual exercise but take that same line in the opposite direction up and to the left. You will be able to locate the red planet Mars because of its colour. Mars is red and does not twinkle.
Continuing upwards and left of Mars you will be able to spot the ringed planet Saturn. Again, it’s significantly bright and glows steadily. Like the other planets, no twinkling.
Saturn is a visual treasure in a telescope and even moderate-sized telescopes will reveal the magnificent rings. So this opportunity is there for the taking but if this is your first attempt at sky watching, don’t be discouraged if you are not locating the celestial objects. You certainly won’t miss the moon! From the upper left, about 20 degrees above the W horizon is Saturn, next down to Mars, then bright Venus and finally tiny Mercury at the WNW horizon.
July 15: Again looking W around one to two hours after sunset, locate the moon down near the horizon. This time we have grouping of three planets with brightest Venus to the far right of the moon. The red planet Mars will appear 7 degrees above the moon while Saturn will be 10 degrees to the upper left of the moon.
Don’t be afraid to try measuring these distances with the arm’s length technique previously described. You won’t look too silly in the dark, right? Amaze your friends with your new knowledge.
July 30: Ah, fresh crisp morning air. Around one hour prior to sunrise, Mars and Saturn will be found near the W horizon. This event is an interesting one in that Saturn will appear less than 2 degrees above Mars. Don’t forget your finger measurement! If you own binoculars, this conjunction will make a fine view.
July 31: Not requiring sleep would be an asset in astronomy but we’re all human. Again one hour before sunrise you can look to the south, find the moon and bright Jupiter will be 7 degrees below the moon.
Yes, we have one this month. Let’s take a moment to remember what a meteor shower really is. People sometimes call meteors “shooting stars.” When a meteor survives passing through Earth’s atmosphere and lands on Earth, it becomes a meteorite. A meteor shower is observed when the planet Earth passes through the remnants from a comet’s tail. The tail is a debris trail of particles that ignite upon contact with our atmosphere. Unfortunately for us this month, the peak of the shower occurs only three days after a full moon & bright moonlight will wash out good viewing opportunities. The Delta Aquarid Meteor Shower peaks before dawn on July 28. The name “Aquarid” refers to the home constellation of Aquaris the Water Bearer.
Within that constellation will be a Radiant Point or point of origin for the shower. f you want to have a look anyway, look south at the moon and you’ll also see the planet Jupiter to upper left of the moon.
A final comment about future meteor showers. When you know a shower will peak on a certain date, consider watching for a couple of nights before and after the peak date. “Peak” simply means the date of maximum activity but the Earth passes through the comet debris over several days.
But wait until next month for one of the best meteor showers of the year
This event is not in North America but can be seen from Easter Island and southern South America. I mention this to remind people that events happen all the time, day and night. We all appreciate the sunlight and warm temperatures but don’t necessarily receive sunlight from the same position of the globe upon which we all exist.
This event happens because the moon passes in front of the sun and blocks it from sight as seen from the Earth. This blockage is a small shadow along a strip of the Earth’s surface. The strip is called the path of totality and means that the view of the sun will be blocked for small period of time. At the maximum point, the sun will be blacked out for over five minutes. One can expect the temperature to drop, and stars and planets may be seen in the “sudden” night sky.
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