tech2 News StaffAug 13, 2019 10:18:35 IST
If there's one widely-accepted "best" for an annual meteor shower display, it's the Perseids shower. Being among the most easily-visible events for "shooting stars" each year, it's also one of the most popular events in the calendar of astronomy buffs.
This year, though, the show will be less promising than usual. Unlike its peak intensity at 50-60 meteors per hour, the Perseids will be dampened by the near full-moon, which will make it hard to see with the naked eye, according to Space.com.
Still, experts think 10-15 Perseids per hour will be visible. And in our view, that's still a treat worth a trek.
Want to see the best-known meteors of the year?
— NASA JPL (@NASAJPL) August 10, 2019
The best odds of spotting the Perseids meteors are from the darkest possible location, by leaning back to observe as big a patch of sky as you can manage — directly above you. The rates of Perseids visible with the naked eye go up after 10 pm and remain optimum till dawn local time. The later in the night you look at them, the better you're likely to find it.
If you venture out to watch the Perseids earlier in the night, there will be fewer of them visible, but the meteors will have that classic long-tail-comet-appearance, what with it having to graze along a larger distance in the atmosphere.
Those in southern latitudes or closer to the equator can look toward the northeast to see more meteors. The Perseids, however, are best-visible from the Northern Hemisphere. All you need to catch the show is darkness, somewhere comfortable to sit and a bit of patience.
To make sure you're prepared, and spot them at their peak, here's everything you should know about the Perseids.
What are the Perseids?
The largest object known to repeatedly pass by Earth is the Comet Swift-Tuttle. Its last fly-by of Earth was in 1992, during its orbit around the Sun, and the next time will be in 2126. But it will neither be forgotten nor missed in the meanwhile, because Earth flies right through an enormous cloud of dust and debris left behind by the comet in its path, creating the annual Perseid meteor shower.
The Perseids meteor shower is actually just a continuous rain of comet dust and debris heating up as they enter Earth's atmosphere and burn up with a burst of light. The speeds of these meteors can reach up to 59 km per second. Only if a fragment of space rock makes it all the way till the Earth's surface without burning up is it given the term "meteorite."
Most of the rocks in the Perseids meteor shower are much too small — about the size of a grain of sand, according to NASA.
Where to spot the Perseids
For the Perseids, as with any meteor shower, the bulk of meteors are visible when the radiant is high in the sky. Perseid meteors stream from a single point in the sky (the "radiant") in the constellation Perseus, outwards. The radiant is so far north in the sky that it could be tricky to spot the spectacular for observers in the Southern hemisphere.
One easy-to-recognise pattern of stars near the radiant is a "W"-shaped Cassiopeia (visible in the star map below). Jupiter and Saturn will also be in the same region. Shining brightly about 30 degrees above the eastern horizon, the pair will be hard to miss on the night of 13-14 August.
When to watch the Perseids
The radiant for the Perseids is the highest point in the sky in the darkest hour before dawn on 13 August in India, with the maximum visibility around 4 am in the morning, according to the International Meteor Organisation.
It helps to remember that meteor showers are notorious for defying even the best-laid forecasts, so your best bet to spot them is to simply stay prepared and stay patient.
How to watch the Perseids
- Binoculars and telescopes are not much use to see meteor showers since they streak overhead and are best seen without equipment.
- It's crucial you give your eyes some time to adapt to the dark. Catch a dark patch of unobstructed sky and give your eyes 30-45 minutes away from sources of light to adjust.
- NASA advises skywatchers to find a spot sheltered and well away from the city or street lights — a parking lot or a large park ideally and carry a sleeping bag or chair along to ensure you're comfortable.
- If you think you might need your cell phone during this time, lower the amount of blue light and brightness your screen gives off using "night mode". Checking your phone in this mode while skywatching won't affect your night vision as much.
The Perseids shower will likely be at its best in the hours between midnight on 13th August and morning on 14th August, according to Space.com.
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