StarDate

In case you haven’t heard, there’s a big event this afternoon — a total eclipse of the Sun. Totality is visible along a narrow path from Texas to Maine. The parts of the country outside that path will see a partial eclipse.

If you miss it — well, let’s just say it’ll be a long wait until the next great eclipse over the United States.

The next total eclipse visible anywhere will take place on August 12th, 2026. Its path will cross parts of Europe, but most of it will cross the high Arctic.

The next total eclipse visible from anywhere in the United States is on March 30th of 2033, across Alaska. An eclipse in 2044 will catch Montana and North Dakota, but much of its path will be across Canada.

The next great eclipse in the U.S. is on August 12th, 2045. Its path will stretch from northern California, across the Rockies, the southern Plains, and the southeast, all the way to southern Florida. And it really will be a great one — totality will last up to six minutes.

Today’s eclipse belongs to a centuries-long series known as Saros 139. The next eclipse in that series is in 2042, mostly over the western Pacific Ocean.

So enjoy today’s total eclipse — the last one visible from American soil for a long time. And please remember to watch safely — use eclipse glasses or other approved gear to protect your eyes from the power of the unfiltered Sun.

Script by Damond Benningfield

It’s almost time for the year’s big celestial event: a total eclipse of the Sun. Tomorrow afternoon, the Moon will pass directly between Earth and the Sun. That will block the Sun’s disk. The sky will grow dark, with a pink glow around the horizon. Stars and planets will pop into view. And the Sun’s faint outer atmosphere, the corona, will look like silvery ribbons around the Moon.

Totality will be visible along a narrow path. In the United States, it’ll stretch from Eagle Pass, Texas, to Houlton, Maine. Several major cities are along that path; the largest is Dallas. At most, totality will last for a bit less than four and a half minutes.

Skywatchers in the rest of the contiguous U.S. will see a partial eclipse — the Moon will cover only part of the Sun’s disk.

For those lucky enough to find themselves inside the path of totality, it’s perfectly safe to look at the Sun when it’s fully eclipsed. At all other times, though, the Sun is much too bright to look at directly. Even a 99-percent-eclipsed Sun is bright enough to cause eye damage. To see it safely, use proper eclipse glasses, or a piece of welder’s glass — number 14 or darker.

If you’re close to a leafy tree, you can follow the eclipse by looking at the ground — the shadows project tiny images of the eclipsed Sun. You can also look at the shadow of a colander or similar device. So enjoy this beautiful alignment — but do it safely!

More tomorrow.

Script by Damond Benningfield

In the mythology of ancient Egypt, Apep was the serpent god — the rival of Re, the sun god. He chased Re, and sometimes briefly caught him — creating a solar eclipse.

NASA plans to launch an experiment named for the serpent god to study the eclipse on Monday. Instruments will fly on three different rockets. They won’t look at the Sun, though. Instead, they’ll study the effect of the eclipse on the ionosphere — a high-altitude layer of Earth’s atmosphere.

The ionosphere carries an electric charge. It “bends” radio waves, allowing them to travel far around the planet. During the day, sunlight intensifies the charge. At night, the charge lessens.

Scientists want to understand how the ionosphere reacts to the brief loss of sunlight during an eclipse. That should tell them more about the ionosphere overall, and how it changes during the day.

Among other ways, they’ll do so by launching Apep. Three small rockets will take flight from a NASA center in Virginia. The rockets will climb about 200 miles high. They’ll deploy several instruments, which will make observations for seven or eight minutes. Then they’ll parachute back to Earth.

The same instruments flew during last year’s annular eclipse, when the Moon didn’t fully cover the Sun. This year’s flights will allow scientists to compare the results — learning more about how Earth’s atmosphere reacts when the Sun grows darker.

More about the eclipse tomorrow.

Colonial orb-weaver spiders may have some extra work to do on Monday, during a total solar eclipse. During an eclipse in 1991, scientists watched as spiders in Mexico began tearing down their webs as the sky darkened — something they do every evening. When the Sun returned, most of them rebuilt their webs, just as they do every morning.

That’s just one example of how life reacts to eclipses. Like the spiders, many daytime animals start their evening rituals. And many nighttime animals wake up when the eclipse gets started.

During the 2017 eclipse, scientists watched 17 species at a zoo in South Carolina. About three-quarters of the species had some response as the eclipse reached its peak. Some animals acted nervous, while others headed for bed. Some gibbons moved and chattered in ways the zookeepers had never seen before.

Other studies have reported that bats and owls sometimes come out during totality — when the Sun is fully eclipsed. Hippos move toward their nighttime feeding grounds. Bees have been seen to return to their hives and not budge until the next day. And mosquitoes come out — ready to dine on unsuspecting eclipse watchers.

A NASA project is using volunteers to learn more about how animals react. It collected recordings and observations during last year’s annular eclipse, and will repeat the observations this time — telling us more about how the natural world reacts to the vanishing Sun.

Script by Damond Benningfield

A total solar eclipse occurs when the Moon passes in front of the Sun, briefly blocking it from view. Before people understood the science, however, they created legends to explain the Sun’s disappearance. Many of those legends involved animals or mythical monsters.

In China and elsewhere, it was thought the Sun was being devoured by a dragon. People in Vietnam blamed a hungry frog. In Scandinavia, it was a giant wolf set loose by the god Loki. In India, it was the severed head of a monster.

Still others saw an eclipse as a quarrel — or a reunion — between the Sun and Moon. And a story from Transylvania said an eclipse took place when the Sun, which was thought of as female, covered her face in disgust at people’s bad behavior.

In the Choctaw Nation, which originally was based in Mississippi but now is in southeastern Oklahoma, the eclipse was blamed on a black squirrel, Funi Lusa. The story says the squirrel was mischievous. When it got hungry, it started nibbling on the Sun. The startled people yelled and screamed and banged metal objects to scare it away. Men shot arrows and guns into the sky. Eventually, it all worked, and the squirrel left the Sun in peace — sparking a big celebration.

The Choctaw Nation is in the path of next Monday’s total eclipse. The celebration there will include the legend of Funi Lusa — a naughty squirrel that tried to eat the Sun.

More about the eclipse tomorrow.

Script by Damond Benningfield

The Great North American Eclipse is coming up on Monday. The Moon will briefly cover the Sun. That will turn day to night along a narrow path across Mexico, the United States, and Canada.

The timing of the eclipse is known down to the second, and has been for decades. And today, astronomers can predict eclipses far into the future. But making such predictions isn’t easy. It requires a detailed knowledge of the Moon’s orbit around Earth, Earth’s orbit around the Sun, and even the shapes of Earth and the Moon.

People tried to predict eclipses for a long time. Just when they first succeeded is unclear.

There’s little doubt that people have been predicting lunar eclipses for centuries. But lunar eclipses are easier to predict. Earth’s shadow is dozens of times bigger than the Moon’s, so you don’t need to be quite as precise to get it right.

There are stories that the Chinese were predicting solar eclipses more than 4,000 years ago, but no confirmation. An eclipse in 585 BC that stopped a war supposedly was predicted by a Greek scientist, but many modern-day scientists doubt that.

The first confirmed prediction was made by Edmond Halley, using the new laws of gravity devised by Isaac Newton. He forecast that an eclipse would cross England on May 3rd, 1715. And he was right. So the eclipse is known as Halley’s Eclipse — honoring the prediction of an astronomical spectacle.

More about eclipses tomorrow.

Script by Damond Benningfield

On Monday, millions of people will see something they’ve never seen before: the Sun’s corona — its hot outer atmosphere. It extends hundreds of thousands of miles from the surface of the Sun. But it’s so faint that it’s overpowered by the Sun’s brilliant disk. The only time we can see it is during a total solar eclipse.

The corona is made of super-heated gas known as plasma. In fact, the corona is heated to a couple of million degrees Fahrenheit, and sometimes hotter. By comparison, the Sun’s surface is only about 10,000 degrees.

Scientists still aren’t sure just why the corona is so hot. One idea that’s been gaining steam, so to speak, is that the Sun produces millions of “microflares” — small eruptions from its surface. They blast plasma into space.

The plasma thins out as it moves away from the Sun. Eventually, it forms the solar wind — a flow of charged particles that races through the solar system at a million miles per hour or faster.

During a solar eclipse, the corona looks like a silvery halo around the intervening Moon. It may be especially intense during this eclipse because the Sun is nearing the peak of its 11-year magnetic cycle.

One note of caution: It’s safe to look at the Sun when it’s fully eclipsed. At all other times, though, it’s too bright to view without proper eye protection. So stay safe as you view the corona — part of the grandeur of a solar eclipse.

More about the eclipse tomorrow.

Many people dread Mondays and the start of the new work week. But there’s something to look forward to next Monday: the Great North American Eclipse. The Moon will completely cover the Sun, turning the sky dark. Tendrils of light will extend away from the Moon — the Sun’s hot outer atmosphere, the corona. If you can find a way to get to the eclipse path, it’s worth the effort.

For this eclipse, the Moon is a little closer to Earth than average. So the period of totality, when the Sun is fully eclipsed, will last for up to almost four and a half minutes along the centerline of the eclipse path.

That path will first touch land on the Pacific coast of Mexico. The lunar shadow will race toward the northeast, and cross into the United States near Eagle Pass, Texas, at 1:27 p.m. Central Time. It’ll cross over such major cities as Dallas, Indianapolis, Cleveland, and Buffalo. It’ll exit the U.S. at Houlton, Maine, at 3:35 Eastern Time.

Areas outside the path of totality will see a partial eclipse, with the Moon covering only some of the solar disk. The closer a location is to the centerline of the eclipse, the greater the extent of the eclipse.

Remember to look at the Sun directly only during totality. The rest of the time, use eclipse glasses or other protective gear — keeping your eyes safe to enjoy this beautiful cosmic spectacle.

We’ll have more about the eclipse throughout the week.

Script by Damond Benningfield

In Greek mythology, you didn’t have to actually do anything to incur the wrath of the gods. One example is the constellation Crater, the cup, which is in the southeast at nightfall. The story says the god Apollo sent a crow to fetch a cup of water. The crow devoured figs instead, then blamed his delay on a snake. Apollo hurled all three of them into the sky, including the cup — the constellation Crater.

It isn’t much to look at. You need fairly dark skies to see even its brightest stars. But that doesn’t mean there’s nothing interesting within its borders.

One interesting star system is HD 98800. It has four stars, all of which are quite young. In fact, some of them appear to be baby stars that haven’t yet reached maturity. And the system could be giving birth to planets as well.

HD 98800 is perhaps 150 light-years away. Its stars are split into two pairs. The stars in each pair are in fairly tight orbits around each other. The pairs are farther apart, so it takes hundreds of years for them to circle each other.

The system probably is no more than about 10 million years old — compared to four and a half billion years for the Sun. One of its binaries is encircled by wide “doughnuts” of gas and dust — the raw materials for making planets. Gaps in those rings suggest that planets may already be taking shape — in a busy star system in a cup.

Script by Damond Benningfield

The stories behind the constellations don’t always match the pictures we see in the sky. Consider Corvus, which rises in the southeast in mid-evening. In Greek mythology, it represented a naughty crow. The god Apollo sent the crow to fetch a cup of water. Instead, Corvus spent days gorging on fresh figs. He then grabbed a water snake and told Apollo that it had kept him from completing his task. Apollo knew the crow was lying, so he flung Corvus, the cup, and the snake into the sky.

To modern eyes, though, the crow’s brightest stars form the outline of a sail. Going clockwise from the sail’s highest point as it rises, the stars are Delta, Gamma, Epsilon, and Beta Corvi.

A couple of the stars are binaries, with two stars bound together by gravity. But the main stars in those systems, and the single stars in the other two, have a lot in common. They’re all bigger, heavier, and brighter than the Sun. And at least three of them are late in life. They’ve used up all or most of the original hydrogen fuel in their cores. That’s made the stars puff up, which has made them shine much brighter.

Astronomers aren’t sure about the fourth star. It might be in the same phase of life as the others. On the other hand, it might be quite young — just settling into life as a mature star.

Look for the sail — or the crow — in the southeast after about 9:30 or 10. It’s due south after midnight.

We’ll talk about the crow’s water cup tomorrow.

Script by Damond Benningfield