Everything You Need to Know About the Aug. 21 Eclipse
On Aug. 21, all of North America will experience a solar eclipse.
If skies are clear, eclipse-watchers will be able to see a partial solar eclipse over several hours, and some people – within the narrow path of totality – will see a total solar eclipse for a few moments.
How to Watch
It’s never safe to look at the Sun, and an eclipse is no exception. During a partial eclipse (or on any regular day) you must use special solar filters or an indirect viewing method to watch the Sun.
If you have solar viewing glasses, check to make sure they’re safe and undamaged before using them to look at the Sun. Make sure you put them on before looking up at the Sun, and look away before removing them. Eclipse glasses can be used over your regular eyeglasses, but they should never be used when looking through telescopes, binoculars, camera viewfinders, or any other optical device.
If you don’t have eclipse glasses, you can still watch the eclipse indirectly! You can make a pinhole projector out of a box, or use any other object with tiny holes – like a piece of cardstock with a hole, or your outstretched, interlaced fingers – to project an image of the partially eclipsed Sun onto the ground.
Of course, if it’s cloudy (or you’d just rather stay inside), you can watch the whole thing online with us at nasa.gov/eclipselive. Tune in starting at noon ET.
If you’re in the path of totality, there will be a few brief moments when it is safe to look directly at the eclipse. Only once the Moon has completely covered the Sun and there is no light shining through is it safe to look at the eclipse. Make sure you put your eclipse glasses back on or return to indirect viewing before the first flash of sunlight appears around the Moon’s edge.
Why do eclipses happen?
A solar eclipse happens when the Moon passes directly between the Sun and Earth, casting its shadow down on Earth’s surface. The path of totality – where the Moon completely covers the Sun – is traced out by the Moon’s inner shadow, the umbra. People within the Moon’s outer shadow, the penumbra, can see a partial eclipse.
The Moon’s orbit around Earth is tilted by about five degrees, meaning that its shadow usually doesn’t fall on Earth. Only when the Moon lines up exactly between the Sun and Earth do we see an eclipse.
Though the Sun is about 400 times wider than the Moon, it is also about 400 times farther away, making their apparent sizes match up almost exactly. This is what allows the Moon to block out the Sun’s bright face, while revealing the comparatively faint, pearly-white corona.
The Science of Eclipses
Eclipses are a beautiful sight to see, and they’re also helpful for our scientists, so we’re funding eleven ground-based science investigations to learn more about the Sun and Earth.
Total solar eclipses reveal the innermost regions of the Sun’s atmosphere, the corona. Though it’s thought to house the processes that kick-start much of the space weather that can influence Earth, as well as heating the whole corona to extraordinarily high temperatures, we can’t study this region at any other time. This is because coronagraphs – the instruments we use to study the Sun’s atmosphere by creating artificial eclipses – must cover up much of the corona, as well as the Sun’s face in order to produce clear images.
Eclipses also give us the chance to study Earth’s atmosphere under uncommon conditions: the sudden loss of solar radiation from within the Moon’s shadow. We’ll be studying the responses of both Earth’s ionosphere – the region of charged particles in the upper atmosphere – and the lower atmosphere.
All Eyes on the Sky for the August 21 Total Solar Eclipse
Just two months from now, the moon will completely block the sun’s face, treating part of the US to a total solar eclipse.
Everyone in North America will have the chance to see an eclipse of some kind if skies are clear. Anyone within a 70-mile-wide swath of land — called the path of totality — that stretches from Oregon to South Carolina will have the chance to see a total eclipse.
Throughout the rest of the continent, including all 50 United States — and even in parts of South America, Africa, Europe, and Asia — the moon will partially obscure the sun, creating a partial eclipse.
Photo credit: NASA/Cruikshank
An eclipse is one of nature’s most awesome sights, but safety comes first! When any part of the sun’s surface is exposed, use proper eclipse glasses (not sunglasses) or an indirect viewing method, like a pinhole projector. In the path of totality, it’s safe to look directly at the eclipse ONLY during the brief moments of totality.
During a total solar eclipse, the moon blocks out the sun’s bright face, revealing the otherwise hidden solar atmosphere, called the corona. The corona is one of the sun’s most interesting regions — key to understanding the root of space weather events that shape Earth’s space environment, and mysteries such as why the sun’s atmosphere is so much hotter than its surface far below.
This is the first time in nearly 100 years that a solar eclipse has crossed the United States from coast to coast. We’re taking advantage of this long eclipse path by collecting data that’s not usually accessible — including studying the solar corona, testing new corona-observing instruments, and tracking how our planet’s atmosphere, plants, and animals respond to the sudden loss of light and heat from the sun.
We’ll be studying the eclipse from the ground, from airplanes, with research balloons, and of course, from space.
Three of our sun-watchers — the Solar Dynamics Observatory, IRIS, and Hinode, a joint mission led by JAXA — will see a partial eclipse from space. Several of our Earth-observing satellites will use the eclipse to study Earth under uncommon conditions. For example, both Terra and DSCOVR, a joint mission led by NOAA, will capture images of the moon’s shadow from space. Our Lunar Reconnaissance Orbiter will also turn its instruments to face Earth and attempt to track the moon’s shadow as it moves across the planet.
There’s just two months to go until August 21, so make your plans now for the big day! No matter where you are, you can follow the eclipse as it crosses the country with live footage from NASA TV.
Learn more about the upcoming total solar eclipse — including where, when, and how to safely experience it — at eclipse2017.nasa.gov and follow along on Twitter @NASASun.
An all-girls science club from San Fernando Senior High School near Los Angeles has designed a solar-powered tent meant to help homeless and displaced people around the world.
The tent — designed by a group of 12 high schoolers with the help of an organization called DIYgirls — uses solar power to charge electronic devices, provide light and sanitize itself via a system of antibacterial UV lights. And it folds into a backpack for easy travel.
The electronics cost about $40. The tent itself is made out of highly durable and water-resistant material. The idea for the tent came after some members of the team saw increased homelessness in their neighborhood.
“These girls saw a problem in their community,” Evelyn Gomez, an engineer and the executive director of DIYgirls, tells NPR’s Morning Edition. The group aims to get young girls from under-resourced areas interested in the fields of science, technology, engineering, art and math.
Since it’s never safe to look at the partially eclipsed or uneclipsed Sun, everyone who plans to watch the eclipse needs a plan to watch it safely. One of the easiest ways to watch an eclipse is solar viewing glasses – but there are a few things to check to make sure your glasses are safe:
To use solar viewing glasses, make sure you put them on before looking up at the Sun, and look away before you remove them. Proper solar viewing glasses are extremely dark, and the landscape around you will be totally black when you put them on – all you should see is the Sun (and maybe some types of extremely bright lights if you have them nearby).
Never use solar viewing glasses while looking through a telescope, binoculars, camera viewfinder, or any other optical device. The concentrated solar rays will damage the filter and enter your eyes, causing serious injury. But you can use solar viewing glasses on top of your regular eyeglasses, if you use them!
If you don’t have solar viewing glasses, there are still ways to watch, like making your own pinhole projector. You can make a handheld box projector with just a few simple supplies – or simply hold any object with a small hole (like a piece of cardstock with a pinhole, or even a colander) above a piece of paper on the ground to project tiny images of the Sun.
Of course, you can also watch the entire eclipse online with us. Tune into nasa.gov/eclipselive starting at noon ET on Aug. 21!
For people in the path of totality, there will be a few brief moments when it is safe to look directly at the eclipse. Only once the Moon has completely covered the Sun and there is no light shining through is it safe to look at the eclipse. Make sure you put your eclipse glasses back on or return to indirect viewing before the first flash of sunlight appears around the Moon’s edge.
You can look up the length of the total eclipse in your area to help you set a time for the appropriate length of time. Remember – this only applies to people within the path of totality.
Everyone else will need to use eclipse glasses or indirect viewing throughout the entire eclipse!
Photographing the Eclipse
Whether you’re an amateur photographer or a selfie master, try out these tips for photographing the eclipse.
#1 — Safety first: Make sure you have the required solar filter to protect your camera.
#2 — Any camera is a good camera, whether it’s a high-end DSLR or a camera phone – a good eye and vision for the image you want to create is most important.
#3 — Look up, down, and all around. As the Moon slips in front of the Sun, the landscape will be bathed in long shadows, creating eerie lighting across the landscape. Light filtering through the overlapping leaves of trees, which creates natural pinholes, will also project mini eclipse replicas on the ground. Everywhere you can point your camera can yield exceptional imagery, so be sure to compose some wide-angle photos that can capture your eclipse experience.
#4 — Practice: Be sure you know the capabilities of your camera before Eclipse Day. Most cameras, and even many camera phones, have adjustable exposures, which can help you darken or lighten your image during the tricky eclipse lighting. Make sure you know how to manually focus the camera for crisp shots.
sometimes i laugh b/c like. when we first started exploring astronomy, we used our own solar system as a reference, b/c well. it was the closest thing we could study, right? it only makes sense.
only it turns out that the more we study the universe we find that things that are incredibly common in other solar stystems–like binary/trinary star systems, super-earths, hot jupiters, etc, are completely absent from our system
so like. the more we learn about the universe, the more we realize that it’s not just the earth that’s out of the norm, it’s our entire solar system that’s weird compared to the rest of the known universe
On Aug. 21, 2017, everyone in North America will have the chance to see a solar eclipse if skies are clear. We’re giving you a preview of what you’ll see, how to watch and why scientists are particularly excited for this eclipse.
On Aug. 21, within a narrow band stretching from Oregon to South Carolina – called the path of totality – the Moon will completely obscure the Sun, giving people on the ground a view of the total solar eclipse. Outside this path – throughout North America, and even in parts of South America – the Moon will block only a portion of the Sun’s face, creating a partial solar eclipse.
Image credit: T. Ruen
Eclipses happen when the Moon, Sun and Earth line up just right, allowing the Moon to cast its shadow on Earth. Because the Moon’s orbit is tilted with respect to the Sun-Earth plane, its shadow usually passes above or below Earth. But when they all line up and that shadow falls on Earth, we get a solar eclipse.
How to Watch the Eclipse Safely
It’s never safe to look directly at the un-eclipsed or partially eclipsed Sun – so you’ll need special solar viewing glasses or an indirect viewing method, like pinhole projection, to watch at the eclipse.
If you’re using solar viewing glasses or a handheld solar filter, there are a few important safety tips to keep in mind:
Check a few key characteristics to make sure that you have proper solar filters – sunglasses (even very dark ones) or homemade filters are NOT safe
Double-check that your solar filter is not scratched or damaged before you use it
Always put your solar filter over your eyes before looking up at the Sun, and look away from the Sun before removing it
Do NOT use your solar filter while looking through telescopes, binoculars, or any other optical device, such as a camera viewfinder – the concentrated solar rays will damage the filter and enter your eyes, causing serious injury
No solar viewing glasses? Pinhole projection is an easy and safe way to watch the eclipse. You can create a pinhole projector from a box, or simply use any object with tiny holes – like a colander or a piece of cardstock with a hole – to project an image of the Sun onto the ground or a piece of paper.
If you are in the path of totality, there will come a time when the Moon completely obscures the Sun’s bright face. This is called totality, and it is only during this phase – which may last only a few seconds, depending on your location – that it is safe to look directly at the eclipse.
Wherever you are, you can tune into nasa.gov/eclipselive throughout the day on Aug. 21 to hear from our experts and see the eclipse like never before – including views from our spacecraft, aircraft, and more than 50 high-altitude balloons.
A Unique Chance for Scientists
Total solar eclipses provide a unique opportunity to study the Sun and Earth. During a total eclipse, the lower parts of the Sun’s atmosphere, or corona, can be seen in a way that cannot completely be replicated by current human-made instruments.
The lower part of the corona is key to understanding many processes on the Sun, including why the Sun’s atmosphere is so much hotter than its surface and the origins of the Sun’s constant stream of solar material and radiation – which can cause changes in the nature of space and impact spacecraft, communications systems, and orbiting astronauts.
Photo credit: S. Habbal, M. Druckmüller and P. Aniol
For those in the path of totality, the few moments of the total solar eclipse will reveal the Sun’s atmosphere, the corona.
Total solar eclipses are also a chance to study Earth under uncommon conditions: In contrast to the global change in light that occurs every day at dusk and dawn, a solar eclipse changes illumination of Earth and its atmosphere only under a comparatively small region of the Moon’s shadow. This localized blocking of solar energy is useful in evaluating our understanding of the Sun’s effects – temperature, for example – on our atmosphere. Of particular interest is the impact on Earth’s upper atmosphere, where solar illumination is primarily responsible for the generation of a layer of charged particles called the ionosphere.
Prepare for the August total solar eclipse by observing the moon phases this month. Plus, two meteor showers peak at the end of July.
Solar eclipses occur when the new moon passes between the Earth and the sun and moon casts a traveling shadow on Earth. A total solar eclipse occurs when the new moon is in just the right position to completely cover the sun’s disk.
This will happen next month on August 21, when the new month completely blocks our view of the sun along a narrow path from Oregon to South Carolina.
It may even be dark enough during the eclipse to see some of the brighter stars and few planets!
Two weeks before or after a solar eclipse, there is often, but not always, a lunar eclipse. This happens because the full moon, the Earth and the sun will be lined up with Earth in the middle.
Beginning July 1, we can see all the moon’s phases.
Many of the Apollo landing sites are on the lit side of the first quarter moon. But to see these sites, you’ll have to rely on images for lunar orbiting spacecraft.
On July 9, the full moon rises at sunset and July 16 is the last quarter. The new moon begins on July 23 and is the phase we’ll look forward to in August, when it will give us the total solar eclipse. The month of July ends with a first quarter moon.
We’ll also have two meteor showers, both of which peak on July 30. The Delta Aquarids will have 25 meteors per hour between midnight and dawn.
The nearby slow and bright Alpha Capricornids per at 5 per hour and often produce fireballs.