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This Week’s Sky at a Glance, 2019 July 13 – July 20

With the Milky Way becoming prominent on summer evenings, binocular stargazing is a great way to pass the time. A good place to start this year is with Jupiter to pick out its four moons, which look like dimmer stars on either side and change position nightly. Often, one or two might be unseen as they pass in front of or behind the planet. Orange Antares is to the lower right of Jupiter. Check out the colour of this supergiant star, and pick out the globular cluster M4 in the same field of view to its right.

Lower left of Jupiter is the Teapot asterism that makes up much of Sagittarius the Archer. If you extend the two stars at the top of the Teapot’s spout to the right you will find M6, the aptly named Butterfly Cluster. To its lower left is a large star cluster called M7 or Ptolemy’s Cluster. To the right of M7 is a pair of bright stars, Shaula and Lesath, which marks the stinger of Scorpius. They have been nicknamed the Cat’s Eyes.

About a binocular-field width above the teapot’s spout you will find a fuzzy patch with a small cluster of stars in or near it. The fuzzy patch is a cloud of dust and gas called M8, the Lagoon Nebula, where stars are forming. Radiation from hot young stars makes the gas glow, and it can be seen with the naked eye in rural areas. A telescope will reveal dark dust lanes in the nebula that suggest its lagoon name. The cluster of stars is called NGC 6530, where NGC stands for New General Catalogue. Just above M8 is a smaller cloud, M20 or the Trifid Nebula, and the nearby star cluster M21.

This Week in the Solar System

Saturday’s sunrise in Moncton is at 5:40 am and sunset will occur at 9:08 pm, giving 15 hours, 28 minutes of daylight (5:48 am and 9:10 pm in Saint John). Next Saturday the Sun will rise at 5:47 am and set at 9:02 pm, giving 15 hours, 15 minutes of daylight (5:55 am and 9:05 pm in Saint John).

The Moon is full on Tuesday, the Mi’gmaw Birds Shed Feathers Moon. It is near Jupiter this Saturday and near Saturn on Monday, but much of the media focus will be on the 50th anniversary of the Apollo 11 landing next Saturday. Jupiter is at its highest and best for observing in late evening, and telescope users might see its Red Spot around 10 pm on Tuesday and before midnight on Thursday. Saturn trails Jupiter by about two hours in the evening sky, while Mercury, Mars and Venus are too close to the Sun for comfortable viewing.

Members of RASC NB and the Saint John Astronomy Club will be offering views of the night sky at the St, George Summerfest on July 19, and celebrating the 50th anniversary of the Apollo 11 lunar landing on July 20 at the Moonlight Bazaar in Uptown Saint John.

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

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This Week’s Sky at a Glance, 2019 July 6 – July 13

Although Jupiter appears to be in the constellation Scorpius this summer, it is actually within the official borders of Ophiuchus the Serpent Bearer. By being in the constellation I mean passing in front of it. The stars are much farther than the planets, but how much farther? Neptune is the most distant planet from the Sun, about six times farther than Jupiter and 30 times farther than Earth. Sunlight takes 4.2 hours to reach Neptune but 4.2 years to reach the closest star, Proxima Centauri.

Rasalhague, the brightest star of Ophiuchus and which marks his head, is 49 light years away, while the one at his waist is about ten times farther. Rasalhague is closer to us than it is to some of the other stars that form the constellation. The constellation shapes are a matter of perspective but they will look the same from Neptune as they do from Earth.

Centuries ago the area where Jupiter currently resides was shared by Scorpius and Ophiuchus. When the constellation borders were set by the International Astronomical Union in 1930 this area was designated for Ophiuchus and, since the ecliptic runs through here, it became the 13th constellation of the zodiac. But don’t expect to find it in the daily horoscope.

This Week in the Solar System

Saturday’s sunrise in Moncton is at 5:35 am and sunset will occur at 9:12 pm, giving 15 hours, 37 minutes of daylight (5:43 am and 9:14 pm in Saint John). Next Saturday the Sun will rise at 5:40 am and set at 9:08 pm, giving 15 hours, 28 minutes of daylight (5:48 am and 9:10 pm in Saint John).

The Moon is at first quarter on Tuesday, giving great views through binoculars or a telescope all week. Jupiter is at its highest and best for observing in late evening, and telescope users might see its Red Spot around 11 pm on Thursday. Saturn reaches opposition on Tuesday and will be in the evening sky after sunset throughout the summer. Mercury and Mars are very low in the west after sunset, while Venus is very low in the east before sunrise.

The next RASC NB star party will be at Mactaquac Provincial Park on July 5 – 6. The Saint John Astronomy Club meets at the Rockwood Park Interpretation Centre at 7 pm on July 6. All are welcome.

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

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This Week’s Sky at a Glance, 2019 June 29 – July 6

Five millennia ago, Persian and perhaps Egyptian astrologers designated four of the first magnitude stars (the 20 brightest) as Watchers of the Sky, with each guarding one of the four cardinal directions. With their proximity to the Sun at the equinoxes and solstices they were also used to mark seasonal changes. Collectively, they were known as the Royal Stars.

Regulus in Leo and Antares in Scorpius were two of the Royal Stars, and we see them now appearing through evening twilight. Regulus guarded the north and marked the summer solstice, while Antares guarded the west and marked the beginning of autumn. Fomalhaut, in Piscis Austrinus below Aquarius, guarded the south and marked the winter solstice. Aldebaran, currently rising in Taurus less than an hour before sunrise, guarded the east and marked the spring equinox. These stars no longer mark the seasons as they did 5000 years ago due to precession of Earth’s polar axis, which makes one complete wobble every 25,800 years. On the summer solstice, the Sun is now located near the border of Gemini and Taurus.

None of the Royal Stars make the top ten in brightness. The brightest star in the sky for this time of year, Arcturus, is at its highest at sunset. It precedes almost equally bright Vega, which anchors the Summer Triangle with Deneb and Altair. Vega reaches its highest point about half an hour before Fomalhaut rises around 2:30 am. These two stars are the same distance from us, at 25 light years.

This Week in the Solar System

Saturday’s sunrise in Moncton is at 5:30 am and sunset will occur at 9:14 pm, giving 15 hours, 44 minutes of daylight (5:39 am and 9:16 pm in Saint John). Next Saturday the Sun will rise at 5:35 am and set at 9:12 pm, giving 15 hours, 37 minutes of daylight (5:43 am and 9:14 pm in Saint John). Earth is at aphelion on Thursday, its farthest distance from the Sun for the year at 152.1 million kilometres.

The Moon is new on Tuesday, with a very slim crescent forming a triangle with Mercury and Mars on Wednesday after sunset. Jupiter is at its highest and best for observing around midnight, and telescope users might see its Red Spot around 11 pm this Saturday. Saturn is high enough around midnight to give decent views of its magnificent icy rings. Venus can be seen with difficulty in morning twilight, rising 45 minutes before sunrise.

The next RASC NB star party will be at Mactaquac Provincial Park on July 5 – 6. The Saint John Astronomy Club meets at the Rockwood Park Interpretation Centre at 7 pm on July 6. All are welcome.

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

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