Enjoy a conjunction of Venus and Jupiter, and use the Southern Cross to find the South Celestial Pole
When to use this chart
1 April at 00:00 AEDT (13:00 UT)
15 April at 23:00 AEST (13:00 UT)
30 April at 22:00 AEST (12:00 UT)
The chart accurately matches the sky on the dates and times shown for Sydney, Australia. The sky is different at other times as the stars crossing it set four minutes earlier each night.
APRIL HIGHLIGHTS
April includes some rare close meetings of planets, so close that the discs are visible together through telescopes. All are best seen in the east around dawn’s start. The 5th finds Saturn and Mars around 0.3˚ apart. Neptune has two conjunctions, the first with Jupiter, separated by 0.2° on the 13th. Next, Venus is close to Neptune on the 28th, with the east coast seeing them 14 arcseconds apart at 05:10. Venus continues on to Jupiter with a separation of 0.2° on 1 May.
STARS AND CONSTELLATIONS
Recommended equipment: Naked eye
The Southern Cross, standing high in the south, is an iconic sight in April’s evening skies for us down under. Through a low power pair of binoculars (field size of 6˚ minimum) the entire Cross is seen. The Cross also gives a simple way of finding the South Celestial Pole (SCP).
Drawing a line from the top star, Gamma (γ) Crucis, through the bottom star, Alpha (α) Crucis, and extending a further four times this distance gives a position within around 4° of the SCP.
THE PLANETS
Recommended equipment: Naked eye
With Uranus approaching conjunction early in May, this month the evening sky is fairly devoid of planets. In contrast, the mornings are busy. Mars spends April rising around 02:00, with brilliant Venus arriving around an hour later. Neptune and Jupiter travel together this month; rising around the start of dawn they slowly increase in altitude, catching up with Venus by the month’s close. Venus and Jupiter conjunctions are always impressive naked-eye events.
DEEP-SKY OBJECTS
Recommended equipment: Small/medium telescope
This month we visit two very different planetary nebulae in the southern sky. NGC 3132 (RA 10hr 7.0min, dec. -40° 26’), known as the Eight-Burst Nebula, lies close to the border between Vela, the Sails and Antlia, the Pump.
This bright (9th magnitude) planetary nebula has an obvious elliptical-shaped ring (2 arcminutes across), with its interior looking mottled and a prominent central 10th magnitude star. There is a pair of 11th magnitude stars (1 arcminute apart), 2 arcminutes southeast of the nebula.
NGC 5189 (RA 13hr 33.7min, dec. -65° 58’) is rather unusual and is located in Musca, the Fly; it is sometimes called a Spiral Planetary Nebula. Visually, its most prominent feature is a bright, 2 arcminute x 0.5 arcminute bar, with a central, fragmented circular glow that is around 1 arcminute across.
CHART: PETE LAWRENCE