Like every summer, the Earth traverses the trail of dust and rocks left behind by Comet Swift-Tuttle, producing a shower of shooting stars known as Perseids or Tears of Saint Lawrence. This year, this phenomenon has been seen since July 17 and will be visible until August 24. However, the peak time will occur on the nights of August 11-14. Experts believe that the activity of these stars will reach 100 meteors per hour (in 2020 they stayed at 78 and in 2019 they reached 99) and even the smallest will be visible, due to the low luminosity of the Moon on those dates. The busiest night can be followed live, from one fifteen in the morning from Thursday to Friday, in EL PAÍS through the channel sky-live.tv, which broadcasts the event from the Canary Islands Observatory.
This phenomenon was dated for the first time in the year 36, although it was not until 1835 when it received its current name. That year, a Belgian astronomer identified a point in the sky where these lights appeared to be born and that point was in the constellation Perseus. This shower is actually small fragments of dust and rocks left behind by Comet Swift-Tuttle, which “thaws” in solar heat.
This asteroid, 26 kilometers in diameter and discovered in 1862, completes one orbit around our star every 133 years. When its remains, some smaller than a grain of sand, enter the atmosphere, they become incandescent and transform into a beam of light, which from Earth looks like a shooting star. According to experts, this year will be especially active and more than 100 meteors can be seen per hour.
“The fact that there are a few days a year that we have more activity of shooting stars or meteors is mainly due to the passage through the orbit of the comet or asteroid that increases the density of meteoroids in space” explains Miquel Serra, administrator of the Teide Observatory, although it warns that other factors such as light pollution of the place or the lunar cycle may also influence.
When the remnants of Comet Swift-Tuttle enter the atmosphere, they turn incandescent and transform into a beam of light, which from Earth looks like a shooting star.
For astronomers it is important to know the amount of rain that is going to fall, since with it they can calculate the density of that cloud of debris in orbit, which is known as meteoroids. “Knowing exactly the size and density of these meteors is important to protect our fleet of satellites,” says Serra. This infrastructure would be the first to receive the impact of this cloud, so it is key to anticipate in case it is very dense or there are large fragments.
The Perseids 2021 can be followed in El País thanks to the signal of sky-live.tv from one fifteen in the morning on August 13 (Spanish peninsular time) and through the aforementioned television channel on Youtube. The low luminosity of our satellite (there will be a new moon on August 8) will allow us to see even the smallest asteroids.
In addition, the Canary Islands Astrophysics Institute and the Polytechnic University of Madrid have launched a project called Star counters so that any citizen can collaborate in the meteor count. The Institute itself has made available to astronomy fans a guide to follow the entire process through mobile applications. “It is about counting the number of shooting stars that have passed through your field of vision and sending this data to a portal and together making a very precise calculation of the activity of the Perseids as a function of time and very interesting results can be obtained. ”Says the administrator, who encourages doing the activity as a family.