Christopher Palma, Penn State

During a solar eclipse, astronomers who study heliophysics are able to study the Sun’s corona – its outer atmosphere – in ways they are unable to do at any other time.

The brightest part of the Sun is so bright that it blocks the faint light from the corona, so it is invisible to most of the instruments astronomers use. The exception is when the Moon blocks the Sun, casting a shadow on the Earth during an eclipse. But as an astronomer, I know eclipses are rare, they last only a few minutes, and they are visible only on narrow paths across the Earth. So, researchers have to work hard to get their equipment to the right place to capture these short, infrequent events.

In their quest to learn more about the Sun, scientists at the European Space Agency have built and launched a new probe designed specifically to create artificial eclipses.

Meet Proba-3

This probe, called Proba-3, works just like a real solar eclipse. One spacecraft, which is roughly circular when viewed from the front, orbits closer to the Sun, and its job is to block the bright parts of the Sun, acting as the Moon would in a real eclipse. It casts a shadow on a second probe that has a camera capable of photographing the resulting artificial eclipse.

Having two separate spacecraft flying independently but in such a way that one casts a shadow on the other is a challenging task. But future missions depend on scientists figuring out how to make this precision choreography technology work, and so Proba-3 is a test.

This technology is helping to pave the way for future missions that could include satellites that dock with and deorbit dead satellites or powerful telescopes with instruments located far from their main mirrors.

The side benefit is that researchers get to practice by taking important scientific photos of the Sun’s corona, allowing them to learn more about the Sun at the same time.

An immense challenge

The two satellites launched in 2024 and entered orbits that approach Earth as close as 372 miles (600 kilometers) – that’s about 50% farther from Earth than the International Space Station – and reach more than 37,282 miles (60,000 km) at their most distant point, about one-sixth of the way to the Moon.

During this orbit, the satellites move at speeds between 5,400 miles per hour (8,690 kilometers per hour) and 79,200 mph (127,460 kph). At their slowest, they’re still moving fast enough to go from New York City to Philadelphia in one minute.

While flying at that speed, they can control themselves automatically, without a human guiding them, and fly 492 feet (150 meters) apart – a separation that is longer than the length of a typical football stadium – while still keeping their locations aligned to about one millimeter.

They needed to maintain that precise flying pattern for hours in order to take a picture of the Sun’s corona, and they did it in June 2025.

The Proba-3 mission is also studying space weather by observing high-energy particles that the Sun ejects out into space, sometimes in the direction of the Earth. Space weather causes the aurora, also known as the northern lights, on Earth.

While the aurora is beautiful, solar storms can also harm Earth-orbiting satellites. The hope is that Proba-3 will help scientists continue learning about the Sun and better predict dangerous space weather events in time to protect sensitive satellites.

Christopher Palma, Teaching Professor of Astronomy & Astrophysics, Penn State

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Elizabeth W. Covington, Auburn University

Imagine this: You’re at your doctor’s office with a sore throat. The nurse asks, “Any allergies?” And without hesitation you reply, “Penicillin.” It’s something you’ve said for years – maybe since childhood, maybe because a parent told you so. The nurse nods, makes a note and moves on.

But here’s the kicker: There’s a good chance you’re not actually allergic to penicillin. About 10% to 20% of Americans report that they have a penicillin allergy, yet fewer than 1% actually do.

I’m a clinical associate professor of pharmacy specializing in infectious disease. I study antibiotics and drug allergies, including ways to determine whether people have penicillin allergies.

I know from my research that incorrectly being labeled as allergic to penicillin can prevent you from getting the most appropriate, safest treatment for an infection. It can also put you at an increased risk of antimicrobial resistance, which is when an antibiotic no longer works against bacteria.

The good news? It’s gotten a lot easier in recent years to pin down the truth of the matter. More and more clinicians now recognize that many penicillin allergy labels are incorrect – and there are safe, simple ways to find out your actual allergy status.

A steadfast lifesaver

Penicillin, the first antibiotic drug, was discovered in 1928 when a physician named Alexander Fleming extracted it from a type of mold called penicillium. It became widely used to treat infections in the 1940s. Penicillin and closely related antibiotics such as amoxicillin and amoxicillin/clavulanate, which goes by the brand name Augmentin, are frequently prescribed to treat common infections such as ear infections, strep throat, urinary tract infections, pneumonia and dental infections.

Penicillin antibiotics are a class of narrow-spectrum antibiotics, which means they target specific types of bacteria. People who report having a penicillin allergy are more likely to receive broad-spectrum antibiotics. Broad-spectrum antibiotics kill many types of bacteria, including helpful ones, making it easier for resistant bacteria to survive and spread. This overuse speeds up the development of antibiotic resistance. Broad-spectrum antibiotics can also be less effective and are often costlier.

Why the mismatch?

People often get labeled as allergic to antibiotics as children when they have a reaction such as a rash after taking one. But skin rashes frequently occur alongside infections in childhood, with many viruses and infections actually causing rashes. If a child is taking an antibiotic at the time, they may be labeled as allergic even though the rash may have been caused by the illness itself.

Some side effects such as nausea, diarrhea or headaches can happen with antibiotics, but they don’t always mean you are allergic. These common reactions usually go away on their own or can be managed. A doctor or pharmacist can talk to you about ways to reduce these side effects.

People also often assume penicillin allergies run in families, but having a relative with an allergy doesn’t mean you’re allergic – it’s not hereditary.

Finally, about 80% of patients with a true penicillin allergy will lose the allergy after about 10 years. That means even if you used to be allergic to this antibiotic, you might not be anymore, depending on the timing of your reaction.

Why does it matter if I have a penicillin allergy?

Believing you’re allergic to penicillin when you’re not can negatively affect your health. For one thing, you are more likely to receive stronger, broad-spectrum antibiotics that aren’t always the best fit and can have more side effects. You may also be more likely to get an infection after surgery and to spend longer in the hospital when hospitalized for an infection. What’s more, your medical bills could end up higher due to using more expensive drugs.

Penicillin and its close cousins are often the best tools doctors have to treat many infections. If you’re not truly allergic, figuring that out can open the door to safer, more effective and more affordable treatment options.

How can I tell if I am really allergic to penicillin?

Start by talking to a health care professional such as a doctor or pharmacist. Allergy symptoms can range from a mild, self-limiting rash to severe facial swelling and trouble breathing. A health care professional may ask you several questions about your allergies, such as what happened, how soon after starting the antibiotic did the reaction occur, whether treatment was needed, and whether you’ve taken similar medications since then.

These questions can help distinguish between a true allergy and a nonallergic reaction. In many cases, this interview is enough to determine you aren’t allergic. But sometimes, further testing may be recommended.

One way to find out whether you’re really allergic to penicillin is through penicillin skin testing, which includes tiny skin pricks and small injections under the skin. These tests use components related to penicillin to safely check for a true allergy. If skin testing doesn’t cause a reaction, the next step is usually to take a small dose of amoxicillin while being monitored at your doctor’s office, just to be sure it’s safe.

A study published in 2023 showed that in many cases, skipping the skin test and going straight to the small test dose can also be a safe way to check for a true allergy. In this method, patients take a low dose of amoxicillin and are observed for about 30 minutes to see whether any reaction occurs.

With the right questions, testing and expertise, many people can safely reclaim penicillin as an option for treating common infections.

Elizabeth W. Covington, Associate Clinical Professor of Pharmacy, Auburn University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Stephanie N. Del Tufo, University of Delaware

Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, send it to CuriousKidsUS@theconversation.com.

“Do we need to read, or can we just get everything through audio, like podcasts and audiobooks?” – Sebastian L., 15, Skanderborg, Denmark

Let’s start with a thought experiment: Close your eyes and imagine what the future might look like in a few hundred years.

Are people intergalactic travelers zooming between galaxies? Maybe we live on spaceships, underwater worlds or planets with purple skies.

Now, picture your bedroom as a teenager of the future. There’s probably a glowing screen on the wall. And when you look out the window, maybe you see Saturn’s rings, Neptune’s blue glow or the wonders of the ocean floor.

Now ask yourself: Is there a book in the room?

Open your eyes. Chances are, there’s a book nearby. Maybe it’s on your nightstand or shoved under your bed. Some people have only one; others have many.

You’ll still find books today, even in a world filled with podcasts. Why is that? If we can listen to almost anything, why does reading still matter?

As a language scientist, I study how biological factors and social experiences shape language. My work explores how the brain processes spoken and written language, using tools like MRI and EEG.

Whether reading a book or listening to a recording, the goal is the same: understanding. But these activities aren’t exactly alike. Each supports comprehension in different ways. Listening doesn’t provide all the benefits of reading, and reading doesn’t offer everything listening does. Both are important, but they are not interchangeable.

Different brain processes

Your brain uses some of the same language and cognitive systems for both reading and listening, but it also performs different functions depending on how you’re taking in the information.

When you read, your brain is working hard behind the scenes. It recognizes the shapes of letters, matches them to speech sounds, connects those sounds to meaning, then links those meanings across words, sentences and even whole books. The text uses visual structure such as punctuation marks, paragraph breaks or bolded words to guide understanding. You can go at your own speed.

Listening, on the other hand, requires your brain to work at the pace of the speaker. Because spoken language is fleeting, listeners must rely on cognitive processes, including memory to hold onto what they just heard.

Speech is also a continuous stream, not neatly separated words. When someone speaks, the sounds blend together in a process called coarticulation. This requires the listener’s brain to quickly identify word boundaries and connect sounds to meanings. Beyond identifying the words themselves, the listener’s brain must also pay attention to tone, speaker identity and context to understand the speaker’s meaning.

‘Easier’ is relative – and contextual

Many people assume that listening is easier than reading, but this is not usually the case. Research shows that listening can be harder than reading, especially when the material is complex or unfamiliar.

Listening and reading comprehension are more similar for simple narratives, like fictional stories, than for nonfiction books or essays that explain facts, ideas or how things work. My research shows that genre affects how you read. In fact, different kinds of texts rely on specialized brain networks. Fictional stories engage regions of the brain involved in social understanding and storytelling. Nonfiction texts, on the other hand, rely on a brain network that helps with strategic thinking and goal-directed attention.

Reading difficult material tends to be easier than listening from a practical standpoint, as well. Reading lets you move around within the text easily, rereading particular sections if you’re struggling to understand, or underlining important points to revisit later. A listener who is having trouble following a particular point must pause and rewind, which is less precise than scanning a page and can interrupt the flow of listening, impeding understanding.

Even so, for some people, like those with developmental dyslexia, listening may be easier. Individuals with developmental dyslexia often struggle to apply their knowledge of written language to correctly pronounce written words, a process known as decoding. Listening allows the brain to extract meaning without the difficult process of decoding.

Engaging with the material

One last thing to consider is engagement. In this context, engagement refers to being mentally present, actively focusing, processing information and connecting ideas to what you already know.

People often listen while doing other things, like exercising, cooking or browsing the internet – activities that would be hard to do while reading. When researchers asked college students to either read or listen to a podcast on their own time, students who read the material performed significantly better on a quiz than those who listened. Many of the students who listened reported multitasking, such as clicking around on their computers while the podcast played. This is particularly important, as paying attention appears to be more important for listening comprehension than reading comprehension.

So, yes, reading still matters, even when listening is an option. Each activity offers something different, and they are not interchangeable.

The best way to learn is not by treating books and audio recordings as the same, but by knowing how each works and using both to better understand the world.

Hello, curious kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to CuriousKidsUS@theconversation.com. Please tell us your name, age and the city where you live.

And since curiosity has no age limit – adults, let us know what you’re wondering, too. We won’t be able to answer every question, but we will do our best.

Stephanie N. Del Tufo, Assistant Professor of Education & Human Development, University of Delaware

This article is republished from The Conversation under a Creative Commons license. Read the original article.