Look Up! A "Ring of Fire" Eclipse Blazes the Southern Hemisphere

An annular solar eclipse on May 20, 2012 as seen from Chaco Culture National Historical Park in Nageezi, Arizona. Image credit: Stan Honda/AFP/Getty Images

If you're in the Southern Hemisphere, look up tomorrow morning, February 26, and brace yourself. You are going to see the Sun, big and bright as usual—that is, until it turns into a ball of black surrounded by a ring of fire. It’s the sort of sight that begs for two question marks: What is going on up there?? The answer is an annular eclipse. Like its more famous cousin, the total solar eclipse, an annular eclipse involves the moon crossing in front of the Sun. When we’re talking about eclipses, however, not all moons are created equal.

For an eclipse to be “total,” the Sun must be completely obscured by the Moon, leaving only the Sun’s corona shimmering around a black disc. When this happens, the darkest part of the moon’s shadow—the umbra—is cast across the Earth. When viewing this from the zone of totality, where alignment is perfect, day will turn to night (and look around: animals will behave accordingly).

Because the Moon’s orbit is not a perfect circle, it sometimes appears smaller in the sky than at other times. If this “smaller” moon crosses in front of the Sun, you get an annular eclipse. A tremendous black disc will still appear within the Sun but will not obscure our star completely. Rather than witnessing the spectacular view of the Sun’s corona, you’ll see the spectacular view of a fiery sky circle. Day will not turn to night when this happens. Earth at that moment will be in the Moon’s antumbra—that is, a weaker shadow beyond the tip of the umbra.

A swath of South America and Africa—mainly in the southern parts of the continents—will experience this particular eclipse. It will begin on February 26, 2017 at 7:10 a.m. ET, and reach its maximum at 9:58 a.m. NASA Goddard Space Flight Center has a map of the eclipse’s path here. Don’t live in the Southern Hemisphere? Don’t feel left out! On August 24, 2017, a small path across the United States—Oregon to South Carolina—will experience a total solar eclipse.


Another view of the annular eclipse on May 20, 2012 as captured by the joint JAXA/NASA Hinode mission. Image credit: JAXA/NASA/Hinode via Flickr // CC BY 2.0

It’s interesting to consider that every day, a giant ball of fire hangs in the sky and we can never really get a good look at it without going blind. If you’re interested in seeing the eclipse tomorrow in person, you’re going to have to go toe-to-toe with a spherical celestial fusion reactor. Your eyes are no match for this, which means you will need special glasses.

DO NOT WEAR REGULAR SUNGLASSES. Stare at the Sun wearing nothing but Ray-Bans and the only good news will be that you can wear them indoors forever thereafter, because you will be blind. The tinted windows in your car, the x-ray film your friend at the hospital swears will work—none of these things will protect you from a lifetime of charred and lifeless retinas. There are no half measures where the Sun is concerned.

There are four things you can wear to look at an eclipse: welder’s goggles with a 14+ rating; special eclipse glasses; a “pinhole projector”; and a specially filtered telescope. Welding goggles can be found at industrial equipment stores, but be sure to get the correct shade—not just any goggles will do, and there is a good chance you are wrong. Eclipse glasses are available at specialty shops, though you'll need to beware of fakes. If you’re a teacher, you can make the eclipse a class event by allowing your students to make pinhole projectors themselves. It requires nothing more than a cardboard box, paper, and aluminum foil.

If all of this sounds like a bit much, or if it’s a cloudy day where you are, you have options! Our friends at Slooh will be covering it, broadcasting footage of the eclipse with commentary from astronomers and solar scientists. Coverage begins on February 26 at 7:00 a.m. ET.

ESA/Herschel/SPIRE; M. W. L. Smith et al 2017
Look Closely—Every Point of Light in This Image Is a Galaxy
ESA/Herschel/SPIRE; M. W. L. Smith et al 2017
ESA/Herschel/SPIRE; M. W. L. Smith et al 2017

Even if you stare closely at this seemingly grainy image, you might not be able to tell there’s anything to it besides visual noise. But it's not static—it's a sliver of the distant universe, and every little pinprick of light is a galaxy.

As Gizmodo reports, the image was produced by the European Space Agency’s Herschel Space Observatory, a space-based infrared telescope that was launched into orbit in 2009 and was decommissioned in 2013. Created by Herschel’s Spectral and Photometric Imaging Receiver (SPIRE) and Photodetector Array Camera and Spectrometer (PACS), it looks out from our galaxy toward the North Galactic Pole, a point that lies perpendicular to the Milky Way's spiral near the constellation Coma Berenices.

A close-up of a view of distant galaxies taken by the Herschel Space Observatory
ESA/Herschel/SPIRE; M. W. L. Smith et al 2017

Each point of light comes from the heat of dust grains between different stars in a galaxy. These areas of dust gave off this radiation billions of years before reaching Herschel. Around 1000 of those pins of light belong to galaxies in the Coma Cluster (named for Coma Berenices), one of the densest clusters of galaxies in the known universe.

The longer you look at it, the smaller you’ll feel.

[h/t Gizmodo]

Why Do Astronauts Use Space Pens Instead of Pencils?

by Alex Carter

It's often said that NASA spent millions of dollars developing a pen that could write in zero gravity, while the Russians just used pencils. It was a warning about looking for a high-tech solution to a mundane problem, of American excess vs. Russian sensibility.

It's also entirely false.

To understand why NASA was so keen on a workable space pen, you have to understand that the pencil is not suited for space travel. The problem is that they have a habit of breaking, shattering, and leaving graphite dust behind. The wood, too, can make it a serious fire risk in the pressurized, oxygen-rich capsule. All of these common issues become life-threatening hazards in space.

Still, there were attempts to bring pencils into space. In 1965, the agency famously ordered 34 specially designed mechanical pencils in hopes of finding the perfect writing tool for astronauts. But at $128 each, they weren't exactly cheap, and it only got worse when the public got wind of the price. Thankfully, an alternative was not too far behind.

Astronaut Walt Cunningham, pilot of the Apollo 7 mission, uses the Fisher Space Pen while in flight.
Astronaut Walt Cunningham, pilot of the Apollo 7 mission, uses the Fisher Space Pen while in flight.

The Space Pen was invented by Paul Fisher, head of Fisher Pen Company. Unlike a typical pen, the Fisher Space Pen uses compressed nitrogen to force ink out of the nozzle, instead of using gravity to make it flow. This made it the ideal device for writing in space, while upside down, or submerged underwater. It wrote crisp and clean, without the safety concerns of a pencil.

Fisher contacted NASA to give his pens a try in 1965 and in 1967, after months of testing, they were impressed enough to bulk buy 400 of them for future missions. Contrary to those urban legends, NASA didn't commission the pen or contribute any funding to it. The Soviets soon ditched their grease pencils and were eventually buying the same Fisher pens as NASA, too. The price? After a 40 percent discount from Fisher, both space agencies were paying $2.39 a pen.

The Fisher Space Pens made their debut in 1968 on the Apollo 7 mission and have been involved in all manned missions since.

So, the short reason is that astronauts only used pencils when they were waiting for something better to come along. As soon as it did, they switched and never looked back. Even the Russians thought it was a good idea.

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