How to Make Sure Your Eclipse Glasses Are Safe

Fox Photos/Getty Images
Fox Photos/Getty Images

You’re probably already preparing for the August 21 solar eclipse, right? It’s going to be spectacular, especially for those in the path of totality, which stretches across the U.S. from South Carolina to Oregon. No matter where you live, though, if you want to watch the eclipse, you should get ahold of some eclipse glasses. To make sure your glasses are up to safety standards, your specs need to follow a few guidelines from NASA before you look up.

First, you should be able to see the manufacturer’s name and address somewhere on the glasses. There are five brands of eclipse glasses that the American Astronomical Society has verified as meeting eclipse safety standards:

  • American Paper Optics
  • Baader Planetarium (only the AstroSolar Silver/Gold film)
  • Rainbow Symphony
  • Thousand Oaks Optical
  • TSE 17

You should also verify that the glasses list the correct certification information, confirming that they’re safe to use when looking directly at the sun. Somewhere on the glasses it should say that the glasses meet the ISO 12312-2 transmission requirements, and you’ll see an ISO logo from the International Organization for Standardization.

This is what your glasses should look like, according to NASA’s guidelines [PDF]:

An illustration of paper eclipse glasses with the necessary safety standards information circled in red
NASA [PDF]

Even if your glasses have all the right information written on them, make sure to take a second look. Be careful not to use lenses that are wrinkled or those that have scratches on them. They should also be relatively new—don’t use any that are more than three years old.

We previously wrote about Warby Parker's free eclipse glasses, which you can pick up in the company's stores in August. We've reached out to the company about whether their glasses meet these guidelines and will update the story when we hear back.

Read the rest of NASA's eclipse safety recommendations here.

Update: Warby Parker has confirmed that their free eclipse glasses are made by American Paper Optics, a certified brand. View away!

A Lunar Crash May Have Left Behind a Library of Human Civilization on the Moon

Matt Cardy, Getty Images
Matt Cardy, Getty Images

SpaceIL, the Israeli-based private space travel nonprofit backed by billionaire Morris Kahn, came up short in their attempt to land the first commercial payload ever delivered on the Moon. Their Beresheet lander crashed last Thursday, April 11, after a technical glitch prompted its engine to power off and then back on, causing it to come in too fast and strike the lunar surface.

While not ultimately successful, the voyage may have still managed to mark a milestone in the history of lunar exploration. The Arch Mission Foundation, which worked with SpaceIL to put a massive amount of information—including the entirety of Wikipedia—on board, announced this week that the digital library may have survived the impact. That would make it the first substantial repository of knowledge to occupy the Moon.

The data, which was dubbed the Lunar Library, holds an impressive wealth of material—the equivalent of roughly 30 million pages in all. In addition to Wikipedia, there are books selected by Project Gutenberg, 60,000 images, language keys, and a curated selection of music. All of this humanity was packed into 25 nickel discs that are each 40 microns thick. The entire library is roughly the size and shape of a DVD.

Arch Mission Foundation believes that the discs could have survived the impact based on what's known about its trajectory and the crash and is working to confirm its existence. Even if it didn't, there's still something to be said for the idea that "archaeological ruins" of human knowledge now exist there.

The Lunar Library wouldn't be the only human relic left behind. Alan Shepard, the fifth man ever to walk on the Moon in 1971, left golf balls after playing a lunar round. In 1969, the crew of Apollo 11 left a 1.5-inch silicon disk containing goodwill messages from prominent figures in 75 countries written microscopically.

SpaceIL intends to pursue a second lunar lander, with a launch date to be announced. While other countries have landed a vehicle on the Moon—the United States, China, and Russia—this would have marked the first time for a private entity.

[h/t Fast Company]

A Blue Moon—May's Flower Moon—Is Coming Next Month

Matt Cardy/Getty Images
Matt Cardy/Getty Images

Exactly how often is "once in a blue moon"? According to NASA, the celestial occurrence isn't especially rare: A blue moon happens about once every 2.5 years. The next blue moon will appear the night of May 18, 2019, and because the event marks the first full moon of May, it will also be a flower moon.

What Is a Blue Moon?

Instead of describing color, like a blood moon, the term blue moon is reserved for an additional full moon that appears within a certain window of time. There are two types of blue moons: monthly blue moons and seasonal blue moons. A monthly blue moon, the more popular of the two definitions, is the second full moon that occurs in a single calendar month. This usage is fairly recent, and likely originated from an error printed in a 1946 issue of Sky and Telescope magazine.

A seasonal blue moon is the older meaning, and it describes the third moon in a season that has four full moons. Each season—winter, spring, summer, and fall—typically sees three full moons, and in the rare event there are four, the third is singled out as the anomaly. This is sometimes the preferred definition of astronomy-minded people because it's based on natural equinoxes and solstices rather than the Gregorian calendar.

When to See the Blue Flower Moon

The full moon set to light up the night sky in May will be a seasonal blue moon. The time of year it occurs—May—makes it a flower moon. The first full moon of each month has a special name: A worm moon is a full moon in April, and a wolf moon is a full moon in January.

To catch 2019's blue flower moon, look up the night of May 18. The Moon will be at its fullest when it's precisely at 180° ecliptic longitude opposite the Sun—which occurs at 5:11 p.m. ET on May 18.

SECTIONS

arrow
LIVE SMARTER