As the meteor shower peaks, we bring you a primer on the celestial fireworks.

A celestial treat Everything you need to know about the Perseids meteor showerNASA Image
Voices Astronomy Monday, August 13, 2018 - 10:47

Did you miss the free celestial fireworks over the weekend? There’s one more chance for you to witness the Perseids meteor shower on Monday night.

Strong activity is expected for the timeframe 11-13 Aug (Saturday, Sunday and Monday nights).

One can expect about 60-100 meteors per hour and Perseids is certainly one of the most spectacular meteor showers you can experience on this planet.

“The backstory of Perseids is also interesting – it originated from a comet called Swift-Tuttle. At a diameter of 26 km, Comet Swift-Tuttle is one of the largest known objects that periodically visit the near-Earth space. It has an orbital period of 133 years and it last visited in 1992. Scientists think that the Perseid meteors we see nowadays are produced by comet Swift-Tuttle about 25,000 years ago. So every shooting star you see is a tiny messenger from that giant comet Swift-Tuttle long before we invented the alphabet. It is really cool when you think about this as you see the these meteors falling from the sky,” remarks Dr Quanzhi Ye, a planetary scientist based at California Institute of Technology, USA.

The meteors appear to radiate from the constellation Perseus in the sky and hence the name Perseids.

"Observations of these meteors have both scientific and historic interest, with the added piquancy of being identified in folk culture as the ‘tears of Saint Lawrence’ in remembrance of the Saint whose feast day is on 10 August and who was burned alive on a gridiron in 258 AD during the reign of Valerian," says Prof Mark Bailey MBE, a world renowned cometary expert, archaeoastronomy guru and senior member of the International Astronomical Union.

Perseids is one of the most reliable annual meteor showers which produces a lot of bright events in the sky. Historical observations show that Perseids has been a super active meteor shower for a long time.

“Whereas observations of the comet have been identified dating back to Chinese records at least as early as 69 BC, the meteors themselves have been recognised only since around 830 AD.  It would be very interesting to try to identify earlier observations, as they might give us a clue as to the physical evolution of the comet over thousands of years," adds Prof Bailey, who has written scientific literature connecting history, archaeology and astronomy.

This year there is this added advantage that it is going to be new moon phase on August 11. Hence, during the strong activity of Perseids, the moon is expected to be a slender crescent, which will ensure sky is darker than usual.

“The origin of the Perseid meteor shower is explained by tiny particles originating from a comet called Swift-Tuttle. When Earth moves around the Sun, the orbit will, at some point, intersect head-on with a small cloud of material ejected from this comet. This cloud is the outgassing remnant from the comet and causes this meteor shower,” explains Dr Tobias Hinse, a top exoplanetary scientist based at Korea Astronomy and Space Science Institute (KASI), South Korea.

The good thing is that you do not need any expensive equipment like powerful telescopes or advanced binoculars to enjoy the meteor show. In that way, meteor showers are the most democratic cosmic phenomena.

“Because Perseids meteor shower is visible during summer time, it allows us to enjoy the phenomena together with family and/or friends gathered in a garden or in a nearby park because of the favourable weather unlike the case for Geminids meteor shower which occurs in December, when it is too cold or complicated to go outside for people in northern latitudes,” points out Dr Regina Rudawska, a small solar body expert at ESA/ESTEC HQ, Netherlands.

Sparkling meteors or shooting stars are known to excite and interest small kids and school students. Sometimes such instances fire a spark in them to learn more about astronomy and the cosmos. There are plenty of Nobel Laureates and Fields Medalists who have expressed their appreciation for impressive meteor displays in their childhood which in turn inspired them to pursue their journey in science and research. Hence, it is a good time for parents to encourage their kids to go out and enjoy the pristine skies and the fabulous things it has to offer.

If you want to be a serious citizen scientist, you can report your meteor counts and statistics to the International Meteor Organization (based in Belgium), which will compile the observational records every year. Hence, in addition to enjoying the spectacular meteor show, you will be contributing to body of knowledge and database enriching the meteor science and research in this area.

If one can pick a spot with lesser light pollution and look up when it is least cloudy, you are in for a celestial treat!

The author, Dr Aswin Sekhar, is an Indian astrophysicist working for University of Oslo, Norway.