Just a week before the "Great American Eclipse", so are you excited? Or confused? Everyone knows a solar eclipse occurs when our moon slips between the Earth and the Sun.
The Sun, Moon and Earth line up perfectly on Monday August 21! So perfectly that you can witness a total solar eclipse across the USA.
The eclipse lasts for over two hours but total darkness lasts for only a couple of minutes. The exact length depends on your location.
Why is this eclipse so special?? Didn't we just have a solar eclipse a few years ago? Actually the last total solar eclipse visible in the USA happened 38 years ago. You only get a few chances to see them in your entire lifetime. So it's worth a trip to a spot where the total eclipse is visible, somewhere on this narrow path across the USA from coast to coast.
The countdown for the Total Solar Eclipse is nearly over! Before the fun and excitement, here is some information about the Great American Eclipse, plus a few tips for the upcoming event.
The Great American Eclipse of 2017
A total solar eclipse is an astonishing sight where day turns to night with only the Sun's corona showing. This cosmic display occurs where the Sun, Moon, and Earth line up to reveal the Sun's corona. The entire eclipse lasts for almost three hours but you only get a few minutes of totality. The last total solar eclipse in the USA occurred in 1979.
Tomorrow Saturday March 18 the Moon will be closer to Earth than that it has been since 1993!
The "supermoon" appears 14 percent larger and 30 percent brighter than lesser full Moons (as always this is with weather permitting). A casual observer probably won't tell the difference.
This full Moon almost coincides with perigee (which is when the Moon is closest to Earth). That means a very large range of high and low ocean tides. The highest tides lag by a few days depending on your location. For example, here in San Francisco, CA the highest tide (6.5 feet) will be attained on March 22. Any storms at sea now can aggravate coastal flooding. Such an extreme tide is known as a perigean spring tide (spring from the German word springen – to "spring up," and not the spring season).
Try to catch the Moon near the horizon, and it can appear enormous. This is due to the famous “Moon illusion” where a Moon looks incredibly large when it is seen near trees, buildings or other foreground objects. You can check the times for Moonrise and Moonset for your area by going to these websites:
For example, did you know we can see more than half the Moon from Earth? Yes we can actually see 59 percent (almost three-fifths)!
Why? The Moon's rotation is uniform but its rate of revolution is not. So sometimes we see just around the edge of each limb!
The images you see in this article is a small version of a half-gigabyte gigantic image of the Moon. This image was stitched together from images taken by a Moon-orbiting satellite called the Lunar Reconnaisance Orbiter.