LOOK: Lyrid Meteor Shower 2020: Watch It Peak in Night Skies |
All year long as Earth revolves around the sun, it passes through
streams of cosmic debris. The resulting meteor showers can light up night skies
from dusk to dawn, and if you’re lucky you might be able to catch a glimpse.
The next shower you might be able to see is known as the Lyrids. Active
from April 16 to April 28, it is expected to be at its peak from Tuesday night
into Wednesday morning, or April 21-22.
There are records from ancient Chinese astronomers spotting these bursts
of light more than 2,700 years ago. They blaze through the sky at about 107,000
miles per hour and explode about 55 miles up in the planet’s atmosphere. This
shower comes from Comet Thatcher, which journeys around the sun about every 415
years. Its last trip was in 1861 and its next rendezvous near the sun will be
in 2276.
Where meteor showers come from
If you spot a meteor shower, what you’re usually seeing is an icy
comet’s leftovers that crash into Earth’s atmosphere. Comets are sort of like
dirty snowballs: As they travel through the solar system, they leave behind a
dusty trail of rocks and ice that lingers in space long after they leave. When
Earth passes through these cascades of comet waste, the bits of debris — which
can be as small as grains of sand — pierce the sky at such speeds that they burst,
creating a celestial fireworks display.
A general rule of thumb with meteor showers: You are never watching the
Earth cross into remnants from a comet’s most recent orbit. Instead, the
burning bits come from the previous passes. For example, during the Perseid
meteor shower you are seeing meteors ejected from when its parent comet, Comet
Swift-Tuttle, visited in 1862 or earlier, not from its most recent pass in
1992.
That’s because it takes time for debris from a comet’s orbit to drift
into a position where it intersects with Earth’s orbit, according to Bill
Cooke, an astronomer with NASA’s Meteoroid Environment Office.
How to watch
The best way to see a meteor shower is to get to a location that has a
clear view of the entire night sky. Ideally, that would be somewhere with dark
skies, away from city lights and traffic. To maximize your chances of catching
the show, look for a spot that offers a wide, unobstructed view.
Bits and pieces of meteor showers are visible for a certain period of
time, but they really peak visibly from dusk to dawn on a given few days. Those
days are when Earth’s orbit crosses through the thickest part of the cosmic
stream. Meteor showers can vary in their peak times, with some reaching their
maximums for only a few hours and others for several nights. The showers tend to
be most visible after midnight and before dawn.
It is best to use your naked eye to spot a meteor shower. Binoculars or
telescopes tend to limit your field of view. You might need to spend about half
an hour in the dark to let your eyes get used to the reduced light. Stargazers
should be warned that moonlight and the weather can obscure the shows. But if
that happens, there are usually meteor livestreams like the ones hosted by NASA
and by Slooh.
The International Meteor Organization lists a variety of meteor showers
that can be seen in 2020. Or you can find more information about some of the
showers this year that are most likely to be visible below:
Source: nytimes
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