April: Our home galaxy makes impressive viewing

NGC 3576, the Statue of Liberty Nebula, is a spectacular star-forming region in the Sagittarius-Carina arm of the southern Milky Way. Located in the constellation Carina about 9000 light-years from Earth, it is only visible from the southern hemisphere. With an outstretched arm she is holding the torch and might even be wearing a crown – with a little imagination. Within the nebula are very active star formation regions that contribute to the complex shapes and looping filaments surrounding her. Photo: MPAS member Nik Axaris

By far the most impressive sight to see this month is the great arc of the Milky Way galaxy. It stretches all the way from the magnificent region in the east around the constellations Scorpius and Sagittarius, through Crux, Carina and Vela, down to Puppis and Canis Major.

The bright star Acrux, or Alpha Crucis, is a multiple star in Crux that can be resolved by a small telescope. In Hydra, the galaxy M83, also known as the Southern Pinwheel, is an excellent large-aperture telescope object.

This is the perfect time of the year for observing the dark nebula known as the Coalsack. You will find it nestled within the rich, bright star fields of the Milky Way. It is visible to the naked eye, sitting right next to Crux, aka the Southern Cross. The Coalsack appears dark because it stops the light from the stars behind it reaching our eyes. An interesting fact is that out of all the constellations, Crux is the smallest. The whole constellation should fit behind your hand at arm’s length.

The Lyrid Meteor Shower is usually active between April 16 and 25 every year. This year it will peak around April 22 or 23, and at most you could expect to see up to 18 meteors an hour. Named after the constellation Lyra, the Lyrids are one of the oldest recorded meteor showers, and according to some historical Chinese texts the shower was seen more than 2500 years ago. The fireballs in the meteor shower are created by debris from comet Thatcher, which takes about 415 years to orbit the sun. The comet is expected to be visible from Earth again in 2276.

Comet 12P/Pons-Brooks is currently in our observable sky and reaches peak brightness on April 21, when it passes perihelion – the point in its orbit at which it is closest to the sun. Comet 12P/Pons-Brooks has been also observed in 1385 and 1457.

By Nerida Langcake
This article appeared in the April 2024 issue of the Mornington Peninsula Magazine.