By Chris Skeldon 
A meteor shower can be seen in Portugal on Sunday. This is the astronomical phenomenon known as Eta Aquaridas, caused by debris that fell from Comet Halley as it orbited the Sun.
These leftover gravel and dust fall into Earth's atmosphere every six months. Due to friction, these small fragments ignite and form so-called “shooting stars.” When they occur in large numbers, they cause a “star shower” or meteor shower, like the ones we can see this weekend (and a few more days), with maximum activity expected Sunday night.
Eta Aquaridas usually occurs at this time of year, while a similar phenomenon in October is called Orionidas.
Eta Aquaridas will be most visible from about 10 p.m. this Sunday until Monday morning. This is a good year to observe this phenomenon, as there will be no moonlight until around dawn, so the darkness of the sky will help you enjoy even the faintest meteors.
The best way to observe, according to astronomers, is to go to a place free of light pollution, lie quietly and comfortably on the ground, and look at the night sky.