What planetary events are coming up in the night sky? Read about Venus, Mercury, Mars, Jupiter, Saturn, Uranus and Neptune and what’s going on in our Solar System in Planets at a Glance.
After June 10, planet Mercury will reach far enough west of the Sun for it to become visible just above the east-northeastern horizon from mid-northern latitudes. Its arrival will allow the five bright planets Mercury, Venus, Mars, Jupiter and Saturn to be seen with unaided eyes, arranged in the order of their distance from the Sun. They’ll be observable until almost sunrise for the rest of June. Mercury’s month-long morning apparition will be a rather poor one for observers at mid-northern latitudes, but a good one for anyone in the tropics or farther south. The planet will brighten dramatically during June, ending the month at magnitude -0.7 from an initial brightness of 2.8. Mercury will become easier to see each morning, with peak visibility occurring on June 16, when Mercury will swing to its maximum angle of 23 degrees west of the Sun. Look for the magnitude 0.45 planet shining very low in the east-northeastern sky between 4:30 and 5 a.m. in your local time zone. Much brighter Venus will approach Mercury from the upper right (or celestial west) until they reach a minimum separation of 9.6 degrees on June 20-21. After that, Mercury will outrace Venus to the Sun. Viewed through a telescope during June, Mercury’s disk will appear to decrease in diameter from 10 to 6 arc-seconds, and wax in illuminated phase from 22 to 71 per cent. On June 27 the old Moon’s crescent will shine several degrees to the upper left (or 3.5 degrees to the celestial north) of Mercury.
Venus will continue to gleam brilliantly in the east-northeastern sky during June as it slides sunward through Aries and then Taurus – but it will not climb very high by dawn for mid-northern latitude observers, who will see it most easily between 4 and 5 a.m. local time. The planet will sit at the lower left (eastern) end of a lengthy string of the bright planets Mars, Jupiter, and Saturn. After Mercury appears to Venus’ lower left around June 10, all five planets will be visible in order of their distance from the Sun. During June, Venus will shine at magnitude -3.9. In a telescope, its apparent disk size will decrease from 13.7 to 11.9 arc-seconds and its illuminated phase will wax slightly from 78 to 86%. In a challenging observation, on June 11, Venus will pass telescope-close below (or 1.7 degrees to the celestial south of) 8000 times fainter Uranus. Venus will approach to within 10 degrees west of Mercury on June 20-21, and then their separation will increase. On June 22-23, the planet will pass binoculars-close to the lower right (or celestial south) of the Pleiades star cluster. On June 26, the pretty crescent Moon will shine between Venus and the Pleiades, with Mercury rising to their lower left around 4:30 a.m. local time.
During June, the small, reddish dot of Mars will shine in the southeastern sky for several hours before sunrise. Following its telescope-close conjunction with Jupiter at the end of May, Mars will spend June widening its separation on the left side of that much brighter planet as it travels rapidly prograde eastward through Pisces – except for a shortcut through northern Cetus from June 3 to 8. Mars will brighten slightly over the month, from magnitude 0.67 to 0.46. Telescope views will show a small, 87%-illuminated ruddy disk with mere hints of the dark markings that will be showcased come December. The planet’s apparent disk size will grow from 6.4 to 7.2 arc-seconds. The waning crescent Moon will hop from right to left (or west to east) of Mars on June 22-23, allowing observers in the Southern Ocean region to see the Moon occult Mars around 18:00 GMT on June 22.
Bright, white Jupiter will dominate the southeastern sky in the hours before dawn during June. The magnitude -2.3 planet will begin the month shining a thumb’s width to the upper right (or 2 degrees to the celestial west) of much fainter Mars. That planet will outrun Jupiter on their eastward trek through the stars of Pisces and northern Cetus, widening their separation daily. Jupiter will shine midway along a lengthy string of bright planets arranged in their order from the Sun, namely: Mercury (after June 10), Venus, Mars, Jupiter, and Saturn. Jupiter will be a good telescope target during June. Its four Galilean moons will dance to the east and west of its banded disk, which will grow in apparent size from 37.4 to 40.8 arc-seconds, the Great Red Spot will appear every second or third morning, and the small, round, black shadow of one of the Galilean moons will transit the planet on June 17 and 22. The waning crescent Moon will shine to Jupiter’s lower right (celestial southwest) on June 21, making a nice photo opportunity.
Yellow-tinted Saturn, which has been shining in the eastern pre-dawn sky all spring, will begin to rise before midnight local time from mid-June onward. The bright planets Mercury (after June 10), Venus, Mars, and Jupiter will be strung along the ecliptic to its lower left (or celestial east). On June 5, the eastward prograde motion of the ringed planet through the background stars of eastern Capricornus will slow to a stop as it commences a westward retrograde loop that will last until late October. That event will kick off the prime observing period for the planet. Viewed in a telescope during June, Saturn’s 17.5 arc-seconds-wide globe, adorned with its 41.5 arc-seconds-wide ring system, will be surrounded by a number of its brightest moons. The angle of Saturn’s rings will diminish until March, 2025, so a greater amount of Saturn’s southern hemisphere will extend below its ring plane this year. The waning gibbous Moon will pass less than 6 degrees below (or celestial south) of Saturn on June 18.
Uranus’ steady march away from the pre-dawn Sun will allow the planet to become increasingly observable in the lower part of the eastern sky during June – but the magnitude 5.8 planet won’t climb high enough in a dark sky for clear telescopic views from mid-northern latitudes until beyond the end of the month. Uranus will shift slowly eastward through southern Aries all month long, forming a triangle less than 2 degrees south of the stars Rho and Pi Arietis, which bear similar magnitudes. On June 12, Uranus will be passed on the south by 10 magnitudes brighter Venus. The waning crescent Moon will hop past Uranus on June 24-25, allowing observers in western and northern Australia and eastern Indonesia to see the Moon occult Uranus before dawn on June 25 – the fifth of 15 consecutive monthly lunar occultations of the seventh planet.
Neptune will spend June in the southeastern sky near the western border of Pisces, flanked by the bright planets Jupiter and Saturn to its east and west, respectively. The blue, magnitude 7.8 planet will rise during the wee hours, allowing it to be observed through good binoculars and backyard telescopes in the dark sky preceding dawn. In a telescope Neptune will show a 2.3 arc-seconds wide-disk. On June 28, its eastward prograde motion through the background stars will slow to a stop in preparation for a westward retrograde loop that will last until early December.
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.