Meteor shower ‘at peak’ this weekend

A major annual meteor shower is forecast to peak at the weekend.

You better look up, because the Eta Aquarid shower is best viewed from the Southern Hemisphere and one of the best observation spots is New Zealand.

The shower is usually most active between April 19 and May 28 and is one of two showers created by dust debris from the Halley’s comet as it orbits the Sun. The other shower is the Orionoid.

The peak hourly rate for meteors in the Aquarid shower is 60 on May 5 and May 6.

It is only visible shortly before dawn from the tropics and Southern Hemisphere.

Space news website EarthSky said the moon is in a waxing phase, which means the moon will set in the early hours, leaving a dark night sky ideal for observing the stars. A report said the meteor shower appears to flow from the constellation Aquarius and a group of stars called the Water Jar.

‘‘Because the Water Jar is on the celestial equator – an imaginary great circle directly above the Earth’s equator – the radiant of the Eta Aquarid shower rises due east as seen from all over the world.

‘‘So you’d think the shower would be about the same as seen from around the globe.

‘‘But it’s not. The reason it’s not is that sunrise comes later to the Southern Hemisphere (where it’s autumn in May) and earlier to the Northern Hemisphere (where it’s spring in May).

‘‘Later sunrise means more dark time to watch meteors. And it also means the radiant point of the Eta Aquarid shower has a chance to climb higher into the predawn sky as seen from more southerly latitudes. That’s why the tropics and southern temperate latitudes tend to see more Eta Aquarid meteors than we do at mid-northern latitudes.’’

A radiant is the point in the sky, as observed from Earth, where meteor showers appear to originate.

The Royal Astronomical Society of New Zealand’s table of southern hemisphere showers said the shower is only visible for a few hours a day, before dawn.

The radiant rises about 2am in New Zealand, making the best time for observation around 5am, the Royal Society says.

Eta Aquarid has been named as the ‘‘meteor of the week’’ by the International Meteor Organisation.