We are approaching the peak of the Perseidsthe August meteor shower known as “tears of San Lorenzo”. Traditionally, “shooting stars” – which are not stars but small meteors that become incandescent upon contact with the Earth’s atmosphere – fall on the night of August 10thbut in reality the Perseid swarm is active from late July to late August, with its peak on August 12th. So by looking up at the sky it is already possible to witness the spectacle of this meteor shower, which is one of the most intense of the year together with the Quadrantids in January, the Orionids in October and the Geminids in December, with the possibility of also seeing 90-100 meteors per hour under ideal conditions.
How to observe the Perseids, the “stars of San Lorenzo”
As already mentioned, the best night for observing the Perseids is that of Monday August 12thpeak of the swarm, even if the Earth is already in full meteor shower these days. The first advice is therefore to go to areas as free from light pollution as possiblebetter if with thefree horizon from buildings or natural reliefs.
Meteors can be observed all night long, but the darkest hours are preferable, so roughly from 11 pm to 4 am, that is after the Moon has set (which on August 12th will be in its first quarter and will wane around 11:30 pm and on August 10th around 11 pm) and before the twilight of dawn. Bear in mind that especially in skies with little light pollution, it takes 20-30 minutes so that our eyes adapt to the dark.
A tip that is not obvious is this: be patient. Meteor showers are unpredictable, so depending on where we are looking and the light conditions, it can take several minutes before we see a “shooting star”. If this happens, don’t despair: it’s normal! Fortunately, the Perseids are one of the most “generous” showers of the year and if you are willing to spend enough time with your nose in the air, it can be very satisfying.
The luminous trails of the meteors will be observable in the whole skyso it is not necessary to look up at any particular point. However, to have the maximum probability of finding shooting stars it is better to point your gaze towards North East and look for the constellation of Perseus: here in fact is the radiant of the meteor shower, that is, the point from which all the meteors appear to come, to the left of the star Miram (Eta Persei). To find the radiant you can use a map like the one below or use apps dedicated to sky observation like Stellarium.
Last but not least: the Perseids are perfectly visible to the naked eye even without the need for special tools. In fact, we advise against using a binoculars or of a telescopewhich would limit our field of view making it more difficult to spot meteors without making observations more detailed or spectacular. On the other hand, you can try to to photograph meteors using some tricks.
How to Photograph the Perseids: Some Helpful Tips
Given that to photograph the Perseids, as well as to observe them, it is a good idea to reach a dark sky with little light pollutionlet’s start from a fundamental assumption: we don’t know in advance in which exact points of the sky we can observe the San Lorenzo meteors. We can’t therefore “aim” at a precise region knowing that we will see something there. Furthermore, the meteors last a few seconds at most; in these conditions, photographing them is therefore not a simple task for those who have no experience.
Having clarified this, if you want to photograph the Perseids you should use a wide angle lens (with focal lengths under 24mm) in order to cover as large an area of sky as possible (and possibly a fish eye lens to observe the entire sky at the same time), place the camera on a tripod photographic and leave the lens open for a relatively long time (a few minutes) in the hope that some meteors will end up in your field of view while you are collecting the image.Chase It can be a good idea especially if you want the photos to also show a nice starry background, possibly with the Milky Way (well visible in dark skies during summer nights in the northern hemisphere), or if you want the image to show as many meteors as possible (the effect is particularly suggestive if you put the radiant of the shower in the center of the field of view). To let in as much light as possible it is good to keep the diaphragm fully open or almost and set values ISO between 800 and 3200.
Once you have all this prepared, your strategy will then be to take images in series (perhaps with a programmable shutter) with exposures of a few minutes until one of these is adorned with a meteor!
