“Jasper was the first one I saw—he didn’t seem to see me at all. His eyes were only for Alice. She went quickly to his side; they didn’t embrace like other couples meeting there. They only stared into each other’s faces, yet, somehow, the moment was so private that I still felt the need to look away.”
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.
Triple treat: Eclipse, comet, full moon all coming Friday night 2/10/17
Penumbral lunar eclipse
Not as spectacular — or noticeable — as a total lunar eclipse, this rather subtle phenomenon occurs when the moon moves through the outer part of Earth’s shadow (known as the penumbra), according to EarthSky.org.
The outer shadow of the Earth blocks part — but not all — of the sun’s rays from reaching the moon, making it appear slightly darker than usual.
Full “snow” moon
As required during any lunar eclipse, the moon will be full Friday night. And this month it’s nicknamed the “snow” moon.
According to the Farmers’ Almanac, full moon names date back to Native Americans in the northern and eastern U.S. Each full moon has its own name.
“The tribes kept track of the seasons by giving distinctive names to each recurring full moon,” the almanac reports. “Their names were applied to the entire month in which each occurred.”
A few hours after the eclipse, Comet 45P, which has been visible after sunset for the past two months through binoculars and telescopes, makes its closest approach to Earth, when it will be “only” 7.4 million miles away, NASA said.
Look to the east around 3 a.m. Saturday morning, where it will be visible in the sky in the constellation Hercules. Binoculars or a telescope could be helpful. Watch for a bright blue-green “head” with a tail.
It will be visible in various points of the night sky until the end of February, according to NASA.
Today’s (Feb. 10) lunar activity comes
in the form of a penumbral
eclipse. What does that mean and how does this type differ from a total
eclipse? Let’s take a look:
First off, what is a penumbra? During a lunar eclipse, two shadows are cast by the Earth. The first is called the umbra (UM bruh). This
shadow gets smaller as it goes away from the Earth. It is the dark center of the
eclipse shadow where the moon is completely in the shadow of the Earth.
The second shadow is called the penumbra (pe
NUM bruh). The penumbra gets larger as it goes away from the Earth. The penumbra
is the weak or pale part of the shadow. This occurs because the Earth is covering a portion of the sun.
Penumbral eclipses occur when only the outer
shadow (the penumbra) of Earth falls on the moon’s surface. This type of eclipse is much more
difficult to observe than total eclipses or when a portion of the moon passes into the umbra. That said, if you’re very
observant, you may notice a dark shadow on the moon during mid-eclipse on
Friday evening. You may not notice anything at all. It’s likely the moon will
just look at little bit darker than normal…like this:
Earth’s penumbral shadow forms a diverging
cone that expands into space in the opposite direction of the sun. From within
this zone, Earth blocks part but not the entire disk of the sun. Thus, some
fraction of the sun’s direct rays continues to reach the most deeply eclipsed
parts of the moon during a penumbral eclipse.
For most of North America, the penumbral
eclipse will begin at moonrise (sunset) on Friday, Feb. 10 and will be obscured by
evening light. Here’s a guide of when to look up:
Fun fact: Aristotle (384 – 322 BCE) first
proved that Earth was round using the curved umbral shadow seen at partial
eclipses. In comparing observations of several eclipses, he noted that Earth’s
shadow was round no matter where the eclipse took place. Aristotle correctly
reasoned that only a sphere casts a round shadow from every angle.
“About three things I was absolutely positive. First, Edward was a vampire. Second, there was a part of him-and I didn’t know how potent that part might be-that thirsted for my blood. And third, I was unconditionally and irrevocably in love with him.”