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This Week’s Sky at a Glance, August 11 – August 18

The main event in the sky this week is the Perseid meteor shower. On any clear night this weekend you will have a better chance of seeing meteors, especially in the wee hours before morning twilight. The peak time is predicted to occur around 10 pm on Sunday when, unfortunately, the constellation Perseus is still low on the northeast. You can see a few meteors per hour any night in a clear, dark sky, but the number increases greatly when Earth passes through a trail of pebbles and dust left by a comet that makes frequent orbits around the Sun. The pebbles left by comet Temple-Tuttle in its 133 year orbit are quite large at a few centimetres, and they enter our atmosphere at a high relative velocity of 60 km/s (Earth travels at 30 km/s). Therefore, they can be very bright.

Meteors, also called shooting stars or falling stars, are the streaks of light created when particles enter the atmosphere at an altitude of about 100 kilometres, and those particles from comets disintegrate before they reach an altitude of 50 kilometres. Many meteors are faint and easily made invisible by moonlight and light pollution. This year the Perseid shower occurs near the new Moon phase so we can expect to see more than usual. They will seem to be coming from a point within the constellation Perseus, which is at its highest in the sky in early morning. You will see fewer in the evening but they tend to be long and bright.

Although a dark sky is preferred for watching meteors, many can still be enjoyed from an urban or suburban area. Get comfortable in a chair, have extra clothes or blankets if you plan to stay long as it can get very chilly, and select a patch of sky that is free of clouds and light. It is better to keep Perseus to your side rather than look in that direction because the meteors will look more spectacular, covering a longer distance. Be very happy if you see about 20-30 per hour on the peak night, or fewer a day before or after. Anything more is a bonus, and this could be a bonus year.

This Week in the Solar System

Saturday’s sunrise in Moncton is at 6:13 am and sunset will occur at 8:34 pm, giving 14 hours, 21 minutes of daylight (6:20 am and 8:37 pm in Saint John). Next Saturday the Sun will rise at 6:22 am and set at 8:22 pm, giving 14 hours of daylight (6:28 am and 8:26 pm in Saint John).

The Moon is new on Saturday, August 11 and it is at first quarter the following Saturday. Venus has a twilight photo opportunity with a slim Moon on Tuesday, and it is at its greatest elongation from the Sun on Friday. Saturn is at its best in the early evening. On Thursday, telescope users might see the shadows of Jovian moons Io and Europa moving across the atmosphere of Jupiter, starting around 9:08 pm and lasting for more than two hours. Mars is in good position for observing by late evening and its global dust storm is weakening. The Perseid meteor shower peaks in a moonless sky Sunday evening and should be active enough to keep most stargazers happy over the weekend and Monday.

The RASC NB star party at Mactaquac Provincial Park takes place this weekend, August 10-11.

Questions? Contact Curt Nason at nasonc@nbnet.nb.ca.

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This Week’s Sky at a Glance, August 4 – August 11

After twilight look for orange Antares in the heart of Scorpius between Jupiter and Saturn. High above the scorpion is a large house-shaped constellation called Ophiuchus the Serpent Bearer. If your area isn’t light polluted you can see two lines of stars rising up and outward from the bottom of the house. The line on the right is Serpens Caput and the one on the left is Serpens Cauda. Together they comprise Serpens the Serpent, the only constellation that is in separate parts. Globular clusters contain many tens of thousands of stars and orbit the centre of our galaxy, which is in the direction where Saturn currently resides. Therefore, these clusters abound in the Sagittarius-Scorpius-Ophiuchus region of our sky and many can be seen in binoculars as a fat, fuzzy star.

Ophiuchus represents Asclepius from mythology, who became interested in the healing arts after killing a snake and watching another snake bring it back to life with a leaf. Asclepius brought many people back from the dead, including Orion after he was killed by the scorpion. Hades, god of the Underworld, complained to Zeus about a decrease in business so Zeus sent his pet eagle to kill Asclepius with a thunderbolt. The constellation of Aquila the Eagle is east of Serpens Cauda.

This Week in the Solar System

Saturday’s sunrise in Moncton is at 6:04 am and sunset will occur at 8:44 pm, giving 14 hours, 40 minutes of daylight (6:12 am and 8:47 pm in Saint John). Next Saturday the Sun will rise at 6:13 am and set at 8:34 pm, giving 14 hours, 21 minutes of daylight (6:20 am and 8:37 pm in Saint John).

The Moon is at third quarter on Saturday, August 4 and it is new the following Saturday, giving a dark sky for meteor watching. Mercury is at inferior conjunction, between Earth and the Sun, on Tuesday and it will be well placed for morning observing toward the end of the month. Venus sets at 10:15 mid-week, when Saturn is at its highest in the south, and Jupiter sets around midnight. Mars looks brilliant to the naked eye but a global dust storm continues to obscure much of its telescopic treasures. The Perseid meteor shower peaks late next weekend but start watching a few nights before then.

The Saint John Astronomy Club meets in the Rockwood Park Interpretation Centre on August 4 at 7 pm. All are welcome. The RASC NB star party at Mactaquac Provincial Park takes place next weekend, August 10-11.

Questions? Contact Curt Nason at nasonc@nbnet.nb.ca.

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This Week’s Sky at a Glance, July 28 – August 4

They say it is the little things that count, and if you are counting constellations there are four little ones lined up in the southeast toward late evening. Start your search with the Summer Triangle, which is composed of the brightest star in each of three constellations: Vega in Lyra the Lyre, Deneb in Cygnus the Swan, and Altair in Aquila the Eagle. Sagitta the Arrow is a distinct shape between Altair and Albireo, which is at the head of Cygnus. The arrow, poisoned with the blood of the Hydra, is one of those shot by Hercules to kill the Stymphalian birds as his sixth Labour.

M27 Dumbbell Nebula (Image by Chuck Ayoub / Wikimedia)

Between Sagitta and Albireo is obscure Vulpecula the Fox, which at one time was two constellations called the Little Fox and the Goose. Vulpecula is known best for having the binocular object M27, the Dumbbell Nebula, within its borders. Below Sagitta is the eye-catching Delphinus the Dolphin, seen leaping out of the watery constellations that hug the horizon below. The dolphin was given its place of honour in the sky by Poseidon for convincing beautiful Amphitrite to be his wife. Below Delphinus and just off the snout of Pegasus the Flying Horse is Equuleus the Little Horse, the second smallest of the 88 constellations. Perhaps representing the foal Celeris, an offspring or brother of Pegasus, it was one of the 48 constellations included in Claudius Ptolemy’s second century map of the sky.

This Week in the Solar System

Saturday’s sunrise in Moncton is at 5:56 am and sunset will occur at 8:53 pm, giving 14 hours, 57 minutes of daylight (6:04 am and 8:56 pm in Saint John). Next Saturday the Sun will rise at 6:04 am and set at 8:44 pm, giving 14 hours, 40 minutes of daylight (6:12 am and 8:47 pm in Saint John).

The full Puny Moon occurs on Friday, July 28, and it is at third quarter on Saturday, August 4. Mars is at opposition on July 27 and closest to Earth on July 31. Normally, the outer planets are closest at opposition but Mars has a more elongated orbit than the others. Its continued sunward motion brings it about 100,000 km closer after opposition before Earth pulls farther ahead in orbit. Mars looks brilliant to the naked eye but a global dust storm still obscures much of its telescopic treasures. Venus shows its nearly half-lit phase in a telescope, best seen in twilight, while Jupiter and its moons and Saturn’s rings more than make up for the Martian disappointment. The South Delta Aquariid meteor shower peaks this Saturday morning, a harbinger of the more prolific Perseid shower in a few weeks.

The Saint John Astronomy Club meets in the Rockwood Park Interpretation Centre on August 4 at 7 pm. All are welcome.

Questions? Contact Curt Nason at nasonc@nbnet.nb.ca

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This Week’s Sky at a Glance, July 21 – July 28

Constellations are not the only stellar figures in the night sky. Any imaginative figure seen that is not one of the 88 constellations is called an asterism. The Big Dipper in Ursa Major and the Sagittarius Teapot are two of the most prominent. Others require binoculars or a telescope, such as the Coathanger and ET star clusters. One I read about in Sky & Telescope magazine a couple of years ago is a smiley face in Cygnus the Swan. Scan with binoculars just below the swan’s right (western) wing near the brightest star in that wing, and look for a pair of eyes above a semicircle grin of five stars. You will probably smile back.

This summer, spend some time scanning the night sky randomly and let your imagination run wild. Pareidolia is a phenomenon in which your mind sees a familiar pattern where none exists. Just as we imagine figures in clouds by day, we can imagine them in the stars at night. Let me know what you see.

This Week in the Solar System

Saturday’s sunrise in Moncton is at 5:48 am and sunset will occur at 9:01 pm, giving 15 hours, 13 minutes of daylight (5:56 am and 9:03 pm in Saint John). Next Saturday the Sun will rise at 5:56 am and set at 8:53 pm, giving 14 hours, 57 minutes of daylight (6:04 am and 8:56 pm in Saint John).

The Moon is near Saturn on Tuesday and is full on Friday, July 28, the Mi’kmaq Birds Shed Feathers Moon. It is also the most distant full Moon of the year – the Puny Moon. I hope you can see it, but most eyes will be on Mars rising at opposition less than half an hour later. Venus, Jupiter, Saturn and Mars stretch from west to east throughout the summer evenings. Mercury is stationary on Wednesday, beginning a two week plunge toward the Sun. The South Delta Aquariid meteor shower peaks on Friday morning, a harbinger of the more prolific Perseid shower in three weeks.

There is public observing at the Irving Nature Park in Saint John on Friday, July 20 at 9 pm (cloud date Saturday, July 21). Friday, July 27 is Astronomy Day at the Huntsman Aquarium in St. Andrews.

Questions? Contact Curt Nason at nasonc@nbnet.nb.ca.

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This Week’s Sky at a Glance, July 14 – July 21

Galaxies are favourite targets for amateur astronomers and many are visible with just binoculars. Two are easily seen with the naked eye in the southern hemisphere: the Large and Small Magellanic Clouds. The Andromeda Galaxy is a naked-eye blur for rural New Brunswickers and it looks majestic in binoculars. But there is one galaxy that is spectacular regardless of your location or observing equipment, and that is our home galaxy.

The Andromeda Galaxy. Image credit and Copyright: Lorenzo Comolli

The Milky Way is at least 110,000 light years across, and although it is composed of 200 billion stars we can distinguish only about 4000 as individual stars from a rural area. The Sun is 27,000 light years from the galactic core, within a spur between the inner Sagittarius and outer Perseus spiral arms. When we look above the spout of the Sagittarius Teapot asterism we are looking toward the galactic core, but vast clouds of dust hide the stars between the spiral arm and the core. South of the head of Cygnus the Swan we see the Milky Way split in two by the Great Rift, one of those dust clouds.

Star formation occurs in clouds of gas and dust within the spiral arms and some can be seen as bright patches with binoculars. Just above the spout of the Teapot is M8, the Lagoon Nebula; and a hint of M20, the Trifid Nebula, can be seen in the same field of view above. Scanning to the upper left up the Milky Way you encounter M17, the Swan (or Omega) Nebula; M16, the Eagle Nebula; and star clusters such as M11, the Wild Duck Cluster in the constellation Scutum the Shield. A tour of the Milky Way under a dark sky can keep a binocular stargazer engaged for an evening.

This Week in the Solar System

Saturday’s sunrise in Moncton is at 5:41 am and sunset will occur at 9:07 pm, giving 15 hours, 26 minutes of daylight (5:49 am and 9:09 pm in Saint John). Next Saturday the Sun will rise at 5:48 am and set at 9:01 pm, giving 15 hours, 13 minutes of daylight (5:56 am and 9:03 pm in Saint John).

The Moon is at first quarter on Thursday, making a great week for public observing events. It passes just above Mercury this Saturday evening, is near Venus on Monday and Jupiter next Friday. Jupiter’s red spot faces our way at 10 pm on Thursday and, under steady sky conditions, it can be seen with a telescope. Saturn continues to give great views of its rings in a telescope. Mars looks awesome in the late evening; its bright yellow-orange colour really catches the eye.

The annual RASC NB star party at Mount Carleton Provincial Park occurs July 13-14, taking advantage of very dark and moonless skies. Public observing events are also scheduled for Thursday, July 19, at the ball field in St. Martins for Old Home Week, and at the Irving Nature Park in Saint John on Friday, July 20 at 9 pm (cloud date Saturday, July 21).

Questions? Contact Curt Nason at nasonc@nbnet.nb.ca.

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