Like every year, this month of May announces the return of the Eta Aquarides. The night of May 6 to 7, when this meteor shower will reach its peak of activity, will be the best time to observe them. It’s not the most spectacular shooting star event of the year, but the luckiest observers will still be able to enjoy some beautiful light trails.
As a reminder, this shower of shooting stars comes from fragments left by Halley’s comet, whose path the Earth crosses twice a year – the second time corresponds to the Orionids, visible in October. Eta Aquarids get their name from the location of their radiant – the point from which all meteors seem to originate, which is in the constellation Aquarius and more specifically near the brightest star Eta Aquarii.
Not very intense, this swarm produces an average of ten meteors per hour at most and up to 30 per hour under the best conditions. At the time of the peak, however, the rate can reach one meteor per minute! But this is difficult to observe from the northern hemisphere, due to the low altitude of the radiant. As usual, to make the most of the show, prefer viewing locations far from any source of light pollution.
To enjoy the show, you will have to get up early!
Maybe some of you have already been able to enjoy the show early this morning? If not, you can try your luck again tonight before dawn, or even Friday as well. The peak of activity is usually centered over three days – May 5-7 this year – but be aware that with a little luck and patience it will be possible to observe shooting stars until May 28.
Note that the second quarter of the Moon will not facilitate too late observations: its luminosity could indeed mask the less intense meteors. The brightest of them should remain visible, however, especially in the hours before dawn. You will therefore have to be early in the morning! To put the odds in your favor, start observing the sky shortly before 3 a.m.
Observers from the southern hemisphere will obviously be privileged: the nights being longer there at this time of year, they will have more time to watch for shooting stars before the Sun rises.
No observation equipment will be required. If the sky is dark and clear, give your eyes time to adjust to the darkness (which may take about twenty minutes), locate the brightest star in the constellation Aquarius – Eta Aquarii is one of the four stars that form the “Y” in the northern part of the constellation – and wait …
The alignment of the radiant and the Eta Aquarii star is of course a coincidence. Eta Aquarii is about 170 light years from Earth, while meteors burn in our atmosphere about 100 km above the Earth’s surface. These are known to be particularly fast, crossing the sky at around 238,000 km / h (or 66 km / s)! The biggest and fastest, the “bolides”, can sometimes leave behind them long light trails (debris that they lose in their wake), which persist from a few seconds to a few minutes.
Halley’s comet, the source of this meteor shower, is arguably one of the best-known comets. Its last perihelion dates back to 1986; the next one is scheduled for July 2061.