NASA defines an eclipse as a cosmic event when one object such as a Moon or a planet moves into the shadow of another. There are two types of eclipses on Earth: an eclipse of the Moon and an eclipse of the Sun, with the former known as lunar eclipses and those involving the Sun dubbed solar eclipses. 2019 kicked-off with a stunning total lunar eclipse on January 21, which was visible across much of the America.
And next year will be no different, with the next – penumbral – lunar eclipse taking place on January 10, 2020.
There are two types of eclipses on Earth: an eclipse of the moon and an eclipse of the sun
Stargazers, however, will not have too wait that long until they can next see an eclipse, as a solar eclipse will occur on December 26, 2019.
Unfortunately for British eclipse aficionados, this three minute-long solar eclipse will only be visible in areas around Australia and Asia, NASA reports.
The December 2019 eclipse event will be an annular solar eclipse, occurring when the Moon’s apparent diameter is smaller than the Sun’s, blocking most of the Sun’s light and causing the Sun to look like an annulus, or ring.
Eclipse: This stunning composite shows the 2015 lunar eclipse in California
Eclipse: Sun spots are seen as the Moon moves into a full eclipse position in Tokyo
How does a lunar eclipse and solar eclipse differ?
A lunar eclipse occurs at night and a solar eclipse occurs during the day.
There are only certain times when either of them can occur.
A lunar eclipse, for example, can only take place when the Moon is directly opposite the Sun in the sky, known as a Full Moon.
Lunar eclipses do not occur every month because the Sun is not exactly in line with the Earth and the Moon.
The moon’s orbit is tilted 5 degrees more than that of the Earth, otherwise, we would witness a lunar eclipse every month.
Lunar eclipses also occur more regularly than their solar namesakes due to proximity.
The Moon is more than 300 times closer than the Sun to the Earth, meaning to celestial orb has a far greater chance of blocking sunlight to the Moon, than vice versa.
Eclipse: The lunar eclipse occurs on January 10, 2020
Eclipse: A timelapse of the ‘Blood Moon’ on September 28, 2015 in Bryanstan, South Africa
Additionally, a lunar eclipse can be seen from a greater portion of the Earth.
Solar eclipses, conversely, are far rarer and can only be seen by a very narrow segment of people on Earth and for a shorter time the they happen.
Another important difference is it is safe to watch a lunar eclipse with the naked eye, as opposed to watching a solar eclipse without eyewear protection, which can seriously damage your eyesight.
A solar eclipse have a more profound effect on humans than the lunar version, due to our nearest star’s importance to life on Earth.
Eclipse: A composite image, the progression of a partial solar eclipse over Washington
Eclipse: A total solar eclipse can be seen in Svalbard, Longyearbyen, Norway in 2015
Why does NASA study eclipses?
When people observed the Moon during an eclipse hundreds of years ago, they learned the Earth’s shape was round.
And even today scientists continue learning about the Moon from lunar eclipses.
In December 2011, NASA’s Lunar Reconnaissance Orbiter gathered data about how quickly the lunar side always facing Earth cools during a lunar eclipse.
This enables NASA to learn what the moon’s surface is composed of, because flat surfaces will cool quickly.
NASA uses this information to calculate which areas of the Moon are rough with boulders and which are flat.
NASA also studies solar eclipses. Scientists use solar eclipses as an opportunity to study the Sun’s corona.
The corona is the top layer of our nearest star. During an annular eclipse, NASA uses ground and space instruments to view the corona when the Moon blocks the Sun’s glare.