Gibbous Moon and Saturn meet on July 15, 2022 | SkyNews
Gibbous Moon and Saturn meet on July 15, 2022 (Chris Vaughan, Starry Night Education)

This Week’s Sky: July 11 to 17, 2022

Look for the gas giants this week as Saturn meets the gibbous Moon and Jupiter re-enters the evening sky

Every week, SkyNews publishes a list of key events in the Canadian sky in This Week’s Sky. This series gives you all the latest news in Solar System movements, including where the planets are in our sky and Moon phases. From eclipses to meteor showers, This Week’s Sky keeps you updated on the best in upcoming astronomical highlights.

Tuesday, July 12 – Asteroid Vesta reverses course (overnight)

Asteroid Vesta reverses course on July 12, 2022 | SkyNews
Asteroid Vesta reverses course on July 12, 2022 (Chris Vaughan, Starry Night Education)

On Tuesday, July 12, the eastward prograde motion of the main belt asteroid designated (4) Vesta through the background stars through central Aquarius will slow to a stop (red path with dates:hour). After tonight Vesta will commence a westward retrograde loop that will last until early October. In mid-July Vesta’s magnitude 6.37 speck will be observable in binoculars (green circle). Look for it several finger widths to the upper right (or 3 degrees to the celestial northwest) of the medium bright star Skat (aka Delta Aquarii) or two finger widths to the right of the fainter star Tau Aquarii. Vesta will rise after 11 p.m. local time and then cross the southern sky until the dawn twilight hides it. Retrograde loops occur when Earth, on a faster orbit closer to the Sun, passes more distant Solar System objects “on the inside track”, making them appear to move backwards across the stars.

Wednesday, July 13 – Full Thunder SuperMoon (at 18:38 GMT)

Full Thunder Supermoon on July 13, 2022 | SkyNews
Full Thunder Supermoon on July 13, 2022 (Chris Vaughan, Starry Night Education)

The Moon will reach its full phase on Wednesday, July 13 at 2:38 p.m. EDT or 11:38 a.m. PDT (18:38 GMT). The July full Moon, commonly called the Buck Moon, Thunder Moon, or Hay Moon, always shines in or near the stars of Sagittarius or Capricornus. The indigenous Ojibwe people of the Great Lakes region call this Moon Abitaa-niibini Giizis, the Halfway Summer Moon, or Mskomini Giizis, the Raspberry Moon. The Cherokees call it Guyegwoni, the Corn in Tassel Moon. The Cree Nation of central Canada calls the June full Moon Opaskowipisim, the Feather Moulting Moon (referring to wild water-fowl habits), and the Mohawks call it Ohiarihkó:wa, the Fruits are Ripened Moon. The Moon only appears full when it is opposite the Sun in the sky, so full moons always rise in the east as the Sun is setting, and set in the west at sunrise. Since sunlight is hitting the Moon face-on at that time, no shadows are cast. All of the variations in brightness you see arise from differences in the reflectivity, or albedo, of the lunar surface rocks. This full Moon will occur only 10 hours after lunar perigee, producing higher tides worldwide and the largest supermoon of 2022. Supermoons shine about 16 per cent brighter and appear six per cent larger than an average full Moon (red circle).

Friday, July 15 – Gibbous Moon and Saturn (overnight)

Gibbous Moon and Saturn meet on July 15, 2022 | SkyNews
Gibbous Moon and Saturn meet on July 15, 2022 (Chris Vaughan, Starry Night Education)

The Moon will begin its monthly trip past the bright planets overnight on Friday, July 15. When the waning gibbous Moon clears the treetops in the southeast after 11 p.m. local time, it will be shining a palm’s width below (or 6 degrees to the celestial south of) the yellowish dot of Saturn. That’s just close enough for them to share the view in binoculars (green circle). Before sunrise, the Moon and Saturn will have moved into the brightening southwestern sky, and the diurnal motion of the sky will have lowered Saturn to the Moon’s right.

Saturday, July 16 – Jupiter enters the evening sky (midnight)

Jupiter enters the evening sky on July 16, 2022
Jupiter enters the evening sky on July 16, 2022 (Chris Vaughan, Starry Night Education)

From mid-July onward, the bright planet Jupiter will rise from the eastern horizon before midnight local time, joining Saturn in the evening sky and kicking our summer planet-viewing into next gear. Jupiter will rise about four minutes earlier each night, allowing even the youngest skywatchers to view it in the coming weeks. Binoculars will show Jupiter’s four Galilean moons dancing to the east and west of the planet. A backyard telescope will better show the moons and reveal dark bands stretching across Jupiter’s large disk. The Great Red Spot will cross the planet every second or third night (inset). From time to time, owners of larger telescopes can catch the small, round, black shadow of one or more of the Galilean moons transiting the planet.

Chris Vaughan is a science writer, geophysicist, astronomer, planetary scientist and an “outreach RASCal.” He writes Astronomy Skylights, and you can follow him on Twitter at @astrogeoguy. He can also bring his Digital Starlab portable inflatable planetarium to your school or other daytime or evening event. Contact him through AstroGeo.ca to tour the Universe together.