THE SOUTHERN HEMISPHERE IN MAY

MAY HIGHLIGHTS

Jupiter is at opposition on the 9th and is at its brightest (mag. –2.5) and largest (44.8 arcseconds) for the year. Being up for the whole night leaves plenty of time to enjoy its cloud banding, the Great Red Spot and the dance of its Galilean satellites as they transit the planet’s disc and pass behind in occultation and eclipse. Occasionally all four moons can gather on the same side of the planet – look out for this happening on the evenings of 17th and 31st or the morning of 26th.

STARS AND CONSTELLATIONS

Orion isn’t the only body in the cosmos to be accompanied by two dogs. Low in May’s northern evening sky lies the constellation of Boötes, the Herdsman, looking like an inverted kite. Preceding him is Canes Venatici, the Hunting Dogs. Named Clara and Asteron, they’re joined to him by a leash. The fourth brightest luminary in the heavens is Boötes’s alpha star, Arcturus. The herdsman is pursuing the Greater Bear (Ursa Major), which isn’t visible from most of Australia.

THE PLANETS

As Venus prepares to depart, low in the northwest twilight, Jupiter can’t be missed rising in the east and remaining visible all night. Following this gas giant is Saturn and then Mars, both visible near the teapot of Sagittarius in the east before midnight. Neptune rises around 01:00 UT mid-month, with Uranus returning from solar conjunction. Mercury concludes its favourable morning return. Dropping towards the Sun, it becomes a dawn-only object by mid-May.

DEEP-SKY OBJECTS

Of all the joys Virgo has to offer, the Sombrero Galaxy is awesome! This spiral galaxy, M104, pictured below, (RA 12h 40.0m, Dec -11° 37’) looks just like its images. A dark equatorial lane bisects the galaxy, reducing its southern hemisphere to a subdued band. M104, aka NGC4594, is located 5° north-northeast from naked-eye star, Eta Corvi. Move 1.1° west-southwest from the Sombrero to find the ‘Stargate’ asterism. It can best be described as two nested triple stars, with the distinctive outer three members (mag. +9.8, +6.7, +6.6) forming a triangle with sides 5 arcseconds long. The inner triple has two prominent (mag. +7.9, +8.3) stars, separated by 29 arcseconds, with a mag. +11.3 companion that forms a rightangled triangle.