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Chart of relative sizes of planets
Past Eclipses Future Eclipses
Past historical solar eclipses: April 16, 1178 BCE - “Odyssey” Eclipse, May 29, 1919 - Einstein’s Eclipse
Future eclipses: August 21, 2017 - total eclipse (USA), April 8, 2024 - total eclipse (USA)

Our Sun is the only star that can be observed directly during the day. We cannot look at the sun with the naked eye because harmful rays could damage our eyes. Safety should come first if you are planning to observe either sunspots or a solar eclipse. Total solar eclipses are one of the most spectacular and easy astronomical events to observe. The view is breathtaking.
So what makes a total solar eclipse so special? Well, it is as if suddenly day switches to night. The sky darkens, and the temperature drops. Flowers close for night, birds roost and get ready to go to sleep, insects stop flying, and bats come out. During a total solar eclipse, you can see the solar corona, the wispy part of the sun that surrounds the disk.

A solar eclipse happens when the Moon passes between the Earth and the Sun, blocking the Sun from our view. A total eclipse is when the Sun is completely blocked out. A partial eclipse happens when the Moon passes slightly above or below the Sun and only blocks out part of it. An annular eclipse is special type of partial eclipse, in which the sun looks like a ring around the dark moon disk. There several main moments in each total solar eclipse. First contact marks the beginning of the partial phase, when the moon disk first touches the sun and begins to cover it. Second contact is the moment when the total phase starts and the moon completely covers the sun. Total phase only lasts several minutes and ends with the third contact, when the sun starts to come back. The fourth contact marks the end of eclipse, when the sun is as bright as it was before.
During a total solar eclipse you can conduct the following observations:
First of all, use special sunglasses or filters specially designed for viewing a solar eclipse. Then, try to observe the different phases of the eclipse and to register the exact moment of each contact.
Your data might be very valuable if you have registered the moment and location of viewing precisely using the GPS. Even though the contact moments are pre-calculated, the real one might be slightly different due to Earth's wobbling.
Only during totality can you remove sunglasses or filters and enjoy the marvelous view of the solar corona. Besides the pale corona sometimes red prominences ,or gigantic eruptions of hot plasma, can also be seen. If you like to draw, try making some sketches. You can also look for some bright stars or planets during the totality.
Photographing the Sun is a little bit complicated, but with some preparation and training you can take beautiful pictures of the solar eclipse.
All you need is a camera with manual control, a lens with a focal length of at least 50 mm and special dark filters that reduce solar light about 10000 times! Only during totality can you remove the filter.
Don't forget about safety and make sure the photos have long exposures from several seconds up to the minute. You can do web research to find what are the best exposure times for your specific camera.
Don't forget to use a tripod, since minor movements will cause the photos to be blurry.
Replace the dark filter right before the end of total phase.
Sometimes sun spots can be seen without magnification.
Try using special sunglasses designed for viewing solar eclipses to protect your eyes when searching for sunspots. In most cases, however, you will need a telescope or at least binoculars. Never look directly at the sun, even through a dark ocular filter. Sun spots look like dark stains. In larger spots you can clearly distinguish a darker central part, called umbra, surrounded by a lighter area called a penumbra. You will notice that the spots usually appear in groups, which form, grow and dissolve over time. Try to sketch them quickly and precisely mark the time. If you observe the sun spots for a few days in row, you will see how the spots evolve and move daily, due to the solar rotation.
angular size of Moon and Sun

We only have eclipses because of the angular size of the Moon. The size of the Moon as seen from Earth is the same as the angular size of the Sun. Of course, the Sun and the Moon are not actually the same size. In reality, the Moon is smaller and closer and the Sun is bigger and farther away. That is what creates the illusion that they are the same size!

solar eclipse icon

Solar eclipses don't happen very often. There are about 70 solar eclipses every century, but most are only partial eclipses. Plus, each eclipse can only be seen from a certain area on Earth. So the chance to see a total solar eclipse is really an once-in-a-lifetime event! The next total solar eclipse visible from North America won't be until 2033!

pin hole camera

The pin hole camera provides the simplest and safest way to observe the Sun. All you need is to punch a small hole with a pin in a sheet of paper, point it to the Sun and hold a second sheet of white paper behind the hole. Move the back sheet of paper back and forth until you get a clear bright circle with sharp ages on the paper. This is the projection of the sun. If you do this during the partial eclipse you will see the crescent shape of the sun disk.

sun spots

Sun spots occur in pairs and groups. During maximum solar activity a dozen different groups might exist at the same time. As a measure of solar activity, astronomers often use the Wolf number W, which is obtained from the equation W=k (10g + f). The total number of the groups is g and f is total number of all individual spots. The k is a factor that depends of your optical system and the experience of the observer. It is typically close to 1. Using the Wolf number we can compare present observations with previous ones, viewed up to 160 years ago, to see how solar activity changes with time.

total eclipse

The complete obscuring of one celestian body by another.

Solar corona

The upper atmosphere of the Sun, visible during a total Solar eclipse.

Solar eclipse

An event when the Moon passes between the Sun and the Earth, blocking our view of the Sun.

total eclipse

The complete obscuring of one celestian body by another.

Partial eclipse

The partial obscuring of one celestial body by another.

annular eclipse

One of the four types of solar eclipses, an annular eclipse happens when the Moon and Sun are perfectly aligned but the Moon does not cover the Sun completely, resulting in the Sun appearing as a bright ring in the sky.

totality

The period during an eclipse when the obscuring of one celestial body is total.

Prominences

Large plumes of plasma emitted from the Sun's surface, which extend into the Sun's corona before looping back.

Sunspots

Temporary, dark spots found on the surface of the Sun, which are caused by intense magnetic activity.

umbra

The darkest part of a shadow, as cast by a celestial body.
Also the dark middle region of a sunspot.

Penumbra

The outer, lighter colored area of a sunspot that surrounds the umbra.