Are you looking for an "out of this world" gift for dad this Father's Day? Then you are in luck, for June 21, 2020, also happens to be the day of a relatively rare annular solar eclipse. The celestial event, which will transform the Sun into a spectacular "ring of fire," will be visible across a narrow, but long, slice of the Eastern Hemisphere. While a larger swath of the world will be able to view a partial eclipse, Americans will miss the event altogether since it will occur on the evening of June 20 and end by sunrise on June 21, 2020.
The annular eclipse will begin in the Democratic Republic of Congo at 4:45 UTC (12:45 PM ET) and sweep through South Sudan, Ethiopia, and Eritrea before crossing over the Red Sea into the Arabian Peninsula. It will then travel through Pakistan, northern India, and southern China before finally ending over Taiwan at 09:34 UTC (5:34 AM ET). Meanwhile, parts of Africa, southeast Europe, Asia, and the Pacific will witness varying degrees of an equally mesmerizing partial solar eclipse.
Solar eclipses, which range from total to partial to annular, can only happen at New Moon, when the Moon is between Earth and the Sun. For a total solar eclipse to occur, the Moon has to be at its closest orbital distance — or about 221,500 miles — from Earth and be perfectly aligned with the Earth and the Sun. As the Moon's shadow falls on Earth, it causes the Sun to briefly "disappear" for those directly in the path of its umbra — the part of the shadow where all sunlight is blocked out. Partial solar eclipses happen when the Moon is not perfectly in line with the two and casts only the outer part of its shadow, the penumbra, on Earth.
Similar to total solar eclipses, annular eclipses require the Sun, Moon, and Earth to be in perfect alignment. However, since the new Moon is almost at apogee or its farthest distance from Earth, it only covers 99 percent of the Sun, causing the fiery star's perimeter to appear as a very bright ring, or annulus, around the Moon's umbra.
If you are among the lucky few in the path of the annular or partial eclipse, be sure to wear protective solar glasses to protect your eyes from the Sun's harmful infrared and ultraviolet radiation, which can result in permanent damage or even blindness. The safest way to watch the eclipse is to join a live-stream online party, such as the one being hosted by Slooh.com at 5:00 UTC on June 21, 2020 . Since this will mean 1:00 AM ET on June 21, 2020 for those of you living in the US, it will also allow for an early start to Father's Day celebrations!
Resources: Space.com, EarthSky.com