Mercury creates tiny solar eclipse in rare celestial act
November 11, 2019
Astronomy aficionados are peering into the sky to watch a rare celestial event that sees the smallest planet of the solar system glide between the sun and the Earth to create a tiny solar eclipse.
In front of the blinding surface of the sun, the planet looks like a tiny jet-black dot. Mercury is 3,000 miles (4,800 kilometers) in diameter, compared with the sun's 864,000 miles (1.4 million kilometers).
The entire 5-hour event is visible, weather permitting, in the eastern United States and Canada, and all of Central and South America. The rest of North America, Europe and Africa can catch part of the action, while Asia and Australia miss out.
Mercury is the closest plant to the sun and its orbit takes about 88 daysImage: picture-alliance/dpa/A. Marchi
A long wait for the next event
The transit is visible from 12:35 p.m. UTC. It will reach the closest to sun's center at approximately 3:20 p.m. UTC and exit around 6:04 p.m. UTC.
Spectators need proper equipment and appropriate eye protection: Telescopes with a minimum magnification of 50x or binoculars with solar filters are recommended.
The last time Mercury transited the Sun was in May 2016, when astronomers managed to capture some amazing pictures and video footage of the event.
It won't make another transit until 2032, when it will be viewable in most of Asia, Europe, Africa, Australia, and South America. People in North America will have to wait even longer, as the next Mercury transit visible to people there won't happen until 2049.
As it passes in front of the blinding surface of the sun, the planet will look like a tiny jet-black dotImage: picture-alliance/ZumaPress/G. Duberstein
A good opportunity
Although the trek appears slow, Mercury zooms across the sun at roughly 150,000 miles per hour (241,000 kilometers per hour).
Scientists have used this kind of transit for hundreds of years to study the way planets and stars move in space, and NASA said teachers and parents shouldn't miss the opportunity to teach children about the solar system.
These events also allow scientists to discover alien worlds. Periodic, fleeting dips of starlight indicate an orbiting planet.
Mercury is the closest plant to the sun and its orbit takes about 88 days. That's much faster than Earth's 365-day orbit and is a much shorter distance — 15,000 kilometers compared with 40,000 kilometers travelled by the Earth on its orbit.
A tiny planet Mercury before the huge sun
One of the smallest planets in our solar system is passing across the sun's face. This is a rare event to observe: it only happens every thirteen to fourteen years on average.
Image: NASA/JHUAPL/Carnegie Institution of Washington
Everybody's looking for the little black dot
A tiny black spot - this is how Mercury looks in front of the solar disk, which it passed on Monday. It took the planet more than seven hours to travel the entire length.
Image: picture-alliance/dpa/K.-J. Hildenbrand
View from Bavaria
An astronomer took those pictures with an 800mm telescope from Kempten in the Allgäu region of Bavaria. The sun is shining with such intensity that the planet is reduced to a small shadow. Even this picture could only be taken because the telescope has been darkened with a special sunray-filter.
Image: picture-alliance/dpa/S. Jansen
Zooming in
This picture is from 2006. Italy's National Institute of Astrophysics took it during a previous Mercury flyby. At least here it is easy to distinguish between the planet and frequently ocurring sunspots, or coronal mass ejections, which also appear as dark spots on the surface of the sun. The planet, however, is clearly round with sharp edges before the background of solar flares.
Image: picture-alliance/dpa/INAF
How to get even closer
Only a spacecraft will do. NASA's spacecraft Messenger took the best pictures of Mercury so far. The probe circled the planet from 2011 to 2015 until it finally crashed there.
Image: picture-alliance/dpa
Just like the Moon?
Messenger found a planet with a surface which does not look too differently from our Earth-Moon - at first glance: rock, sand, gravel and lots of craters left behind by meteorite impacts. But there are big differences, too: temperatures on Mercury are much more extreme. Because there is practically no atmosphere, it can get icy cold. On the other hand, the sun can make it extremely hot.
Image: NASA, JHU APL, CIW
Mercury in all its beauty
This picture is a composite from thousands of pictures taken by different spectrometers in the course of countless orbits around the planet. For the first time, there is a really high-resolution image of Mercury.
Image: Reuters/NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
Messenger's final resting place
This area shows the eventual crash site where Messenger came down in 2015. Clearly visible: meteorite impact craters of all sizes.
Image: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
Highland plains in sunshine
The astronomers who have watched Monday's Mercury flyby did not see pictures like this. The photo taken by Messenger shows an area of plains formed by volcanic activity. The different colors indicate different rock materials.
Image: NASA/JHUAPL/Carnegie Institution of Washington
