Solar Tour Pit Stop #8: Venus

A Swing by Venus

Greetings from the solar tour! We have arrived at Venus.

Venus and Earth are twins, both rocky and similar size and structure.  Studying Venus helps scientists understand what makes Venus inhospitable and Earth habitable.

But Venus is closer to the Sun, and spacecraft that have flown there in the past have only survived a few hours. 

The sounds of Venus

NASA’s Parker Solar Probe is traveling to study the Sun, and flies by Venus to help slingshot it closer to our star.

During a recent flyby of Venus, Parker found that the planet’s upper atmosphere goes through surprising changes over the Sun’s 11-year activity cycle. 

More on what Parker “heard” from Venus

Venus’ nightside

Flying by Venus can give unique and expected views of the inner solar system. 

While flying by Venus, Parker Solar Probe captured this view of Venus’ nightside.

The WISPR instrument captured the image in July 2020 from 7,693 miles away from the planet. More on Parker’s stunning view.

Falling towards the Sun

Thanks to Venus’ gravity, we’ve slowed our orbit to fall even closer to the Sun. Onwards!

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Solar Tour Pit Stop #7: Interplanetary Space

The Space Between

Hello from interplanetary space!

This solar tour stop may seem empty, but there’s more than meets the eye. 

Empty space, full of plasma

If you look closely, the space between the planets is filled with dust, particles, magnetic fields and a mysterious substance called plasma. Hear from scientists Doug Rowland and Don Gurnett as we journey through this mysterious and electrifying substance. 

Weird space

It doesn’t take a rocket scientist to know space is weird. But just how weird might surprise you. Space is dominated by invisible electromagnetic forces that we typically don’t feel. It’s also full of a bizarre state of matter that we don’t usually experience on Earth.

Here are five unearthly things that happen in outer space. 

Kickin’ up dust

Just as dust gathers in corners and along bookshelves in our homes, dust piles up in interplanetary space, too. 

Dust is dispersed throughout the entire solar system, but it collects in rings around the orbits of Earth and Venus. By studying this dust, scientists seek clues to understanding the birth of planets and the composition of all that we see in the solar system.

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Solar Tour Pit Stop #6: L1

Float with NASA’s Fleet at Lagrange Point 1!

Greetings from Lagrange Point 1, or L1, the 6th stop on our solar tour! This is a special place between Earth and the Sun where their gravitational forces are balanced. It’s a great spot for spacecraft because they’ll stay put between the two objects and orbit with Earth, no fuel required.

Q&A with a solar expert

The spacecraft with us here at L1 play a key role in helping us understand the structure of the Sun. Learn more about studying the Sun from afar with solar scientist Ruizhu Chen.

Dr. Chen on studying the Sun

L1, 25 years on

There’s a lot happening on the surface of our Sun, too, and L1 offers a great view of that as well. Equipped with a special tool to see the Sun’s outer atmosphere, NASA’s SOHO mission has been watching the Sun for over 25 years from L1. Check out this video for a glimpse of our star through the decades.

Keep floatin’

That’s a wrap on our time at L1, but in theory we could stay here forever.

We’re now halfway through the Solar Tour before our big announcement. Come back tomorrow for our next stop!

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Solar Tour Pit Stop #5: Earth’s Magnetosphere

Earth’s Protective Shield

Today on our solar tour, we’re exploring the magnetosphere – the last stop before heading into space! Earth’s magnetosphere is created by our planet’s molten core and protects us from the solar wind, the constant stream of radiation and charged particles coming from the Sun!

We’re not alone (magnetically speaking)

Earth isn’t the only object in our solar system with a magnetosphere! This protective shield may be essential for the development of conditions friendly to life, so finding magnetospheres around other planets is a big step toward determining if they could support life.

In this story, learn how not all magnetospheres are created equal.

Magnetic Sun

Earth has a magnetosphere – and so does our Sun!

Before becoming a Delta State University professor and director of the Wiley Planetarium, solar scientist Maria Weber studied how magnetism makes its way to the Sun’s surface by connecting what we see on the surface to what’s happening below. This could help scientists predict solar storms, protecting people and technology on Earth and in space.

Maria Weber Shares the Wonders of Physics and Astronomy

Onward to space!

NASA studies the magnetosphere to better understand its role in our space environment, which can help us learn about the nature of space throughout the universe.

Credit: Trond Abrahamsen

Tomorrow on our solar tour, we’ll head out into space.

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Solar Tour Pit Stop #4: Aurora

Earth’s Polar Light Show

Welcome to the next stop on the solar tour!

Auroras are the bright lights seen at Earth’s north and south poles. 

Energy and particles from the Sun travel to Earth and interact with our planet’s magnetic field. This interaction causes the colorful lights seen in auroras.


People around the poles observe auroras in the night sky! 

Through @TweetAurora, anyone can contribute to aurora science as a citizen scientist! Citizen scientists take photos and help track when and where auroras appear.

Sometimes they discover something entirely new. Like STEVE:

Image Courtesy Krista Trinder

Learn more about STEVE

Launching through the leak

NASA scientists study a strange type of aurora in the Arctic. When these auroras shine, part of Earth’s atmosphere leaks into space! 

Scientists launch rockets through these auroras to better understand the phenomenon. 

Act fast!

Scientists study auroras because it can give us an insight on how our planet’s magnetosphere reacts to space weather. 

We often launch rockets into the aurora because the dancing colors can be fleeting. 

Caption: A NASA-funded GREECE sounding rocket launches into an aurora in the early morning of March 3, 2014, over Venetie, Alaska. The GREECE mission studies how certain structures – classic curls like swirls of cream in coffee – form in the aurora.
Credit: NASA/Christopher Perry
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Solar Tour Pit Stop #3: Earth’s Upper Atmosphere

Earth’s Interface to Space

Welcome to Earth’s upper atmosphere, where things get weird.

Home to:

  • Earth’s hottest (4,500 degrees F) AND coldest (-120 degrees F) temperatures
  • 50 tons of incoming meteors, daily
  • Air that is literally electric
  • Satellite communications

The ionosphere

Lucky for us, the Sun’s most harmful rays don’t reach the ground.

Instead they’re absorbed by Earth’s upper atmosphere. That extra energy breaks atoms into charged particles, creating the electrifying ionosphere.

Earth’s highest clouds

These wispy, high-flying clouds are a perfect blend of Earth and space: they form when water vapor from our air freezes around tiny grains of space dust.

Known as polar mesospheric clouds, NASA’s AIM satellite studies them for subtle clues about changes in our upper atmosphere.

Credit: Maciej Winiarczyk

Learn more

Living in the upper atmosphere

It might look like space out the window, but the International Space Station orbits within Earth’s upper atmosphere.  

Did you know that astronauts can allocate 3.3 lbs (1.5 kg) for personal items? What would you bring to the ISS? 

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Solar Tour Pit Stop #2: Eclipses

A Total Solar Eclipse in Antarctica! 

Early this morning, there was a total solar eclipse across Antarctica! 

During a total solar eclipse, the Moon blocks out the Sun, creating the illusion of night during the day and a breathtaking sight in our sky.

Join NASA Edge at 1:30 p.m. EST on NASA TV to see the eclipse and learn more:

Learning from eclipses

Eclipses have played a major role in scientific discoveries, from the Sun’s structure to the element helium. The corona ­– the Sun’s outer atmosphere – normally can’t be seen because of the bright solar surface, but during an eclipse, the corona emerges, offering unique science opportunities. 

The corona up close

What we can see from the Sun’s corona during an eclipse can teach us a lot about our star. Imagine what we’d learn if we actually touched the corona? NASA has sent Parker Solar Probe to the Sun to do just that. 🛰

Eclipsing right along…

While today’s eclipse may be over, you still have opportunities to watch eclipses in person! An annular solar eclipse will cross the U.S. in 2023, and a total solar eclipse will cross the U.S. in 2024. For now, see what’s next in our #SolarTour by joining in tomorrow.

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Solar Tour Pit Stop #1: Earth

Greetings from Earth!

Our solar tour begins on Earth. From here, one star shines brighter than all the rest. It’s the closest star and the center of our solar system: our Sun. Earth is in the Goldilocks zone, just the right distance from the Sun to be habitable.

 A mission to touch the Sun

We can answer some questions about the Sun from 93 million miles away on Earth, but to learn more, we knew we’d have to venture to our nearest star. In 2018, NASA launched Parker Solar Probe, our mission to touch the Sun.

Why won’t it melt?

Flying close to the Sun is risky business (just ask Icarus), but engineers were up to the task. Check out this video to learn how they built a spacecraft that won’t melt, even when it’s heated to temperatures up to 2500° F. Hint: don’t use wax!

Next stop…?

Now, we’re heading south to catch a special event where day becomes night and the Moon is the star of the show. Can you guess what we’ll see?

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Welcome to NASA’s #SolarTour!

Welcome to NASA’s #SolarTour!

The Sun has an immense influence in space. It shapes and impacts our entire solar system in ways that we are still trying to understand.

To help unravel some of the Sun’s biggest mysteries, NASA launched Parker Solar Probe in 2018 to study the Sun up close.  This year, the mission has big news!

Follow along on our Solar Tour: Starting tomorrow, Dec. 3, we will begin our 12-day journey from Earth to the Sun. Each day, we’ll make pit stops to learn how our Sun influences different places across the solar system. The grand tour will end with Parker Solar Probe’s big announcement on Dec. 14 at our final destination!

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In Earth’s Highest Atmospheric Layers, Space Weather Can Really Heat Things Up

By Miles Hatfield
NASA’s Goddard Space Flight Center

New results from NASA satellite data show that space weather – the changing conditions in space driven by the Sun – can heat up Earth’s hottest and highest atmospheric layer.

The findings, published in July in Geophysical Research Letters, used data from NASA’s Global Observations of the Limb and Disk, or GOLD mission. Launched in 2018 aboard the SES-14 communications satellite, GOLD looks down on Earth’s upper atmosphere from what’s known as geosynchronous orbit, effectively “hovering” over the western hemisphere as Earth turns. GOLD’s unique position gives it a stable view of one entire face of the globe – called the disk – where it scans the temperature of Earth’s upper atmosphere every 30 minutes.

GOLD scans the thermosphere from a position in geostationary orbit, which stays over one particular spot on Earth as it orbits and the planet rotates. Credit: NASA’s Goddard Space Flight Center/Tom Bridgman

“We found results that were not previously possible because of the kind of data that we get from GOLD,” said Fazlul Laskar, who led the research. Dr. Laskar is a research associate at the Laboratory for Atmospheric and Space Physics at the University of Colorado, Boulder.

From its perch some 22,000 miles (35,400 kilometers) above us, GOLD looks down on the thermosphere, a region of Earth’s atmosphere between about 53 and 373 miles (85 and 600 kilometers) high. The thermosphere is home to the aurora, the International Space Station, and the highest temperatures in Earth’s atmosphere, up to 2,700 °F (1,500 °C). It reaches such incredible temperatures by absorbing the Sun’s high-energy X-rays and extreme ultraviolet rays, heating the thermosphere and stopping these types of light from making it to the ground.

graphic showing atmospheric layers on Earth including the heights at which different kinds of airglow appear.
The thermosphere is the highest and hottest atmospheric layer, where the ISS flies and the aurora and airglow can be observed. Credits: NASA’s Goddard Space Flight Center/Genna Duberstein

But the new findings point to some heating not driven by sunlight, but instead by the solar wind – the particles and magnetic fields continuously escaping the Sun.

Animation of the solar wind blowing past Earth. Credit: NASA’s Goddard Space Flight Center/Scientific Visualization Studio/Greg Shirah

The solar wind is always blowing, but stronger gusts can disturb Earth’s magnetic field, inducing so-called geomagnetic activity. Laskar and his collaborators compared days with more geomagnetic activity to days with less, and found an increase of over 160 °F (90 °C) in thermospheric temperatures. Magnetic disturbances, driven by the Sun, were heating up Earth’s hottest atmospheric layer.

Some amount of heating was expected near Earth’s poles, where a weak point in our magnetic field allows some solar wind to pour into our upper atmosphere. But GOLD’s data showed temperature increases across the whole globe – even near the equator, far from any incoming solar wind.

Laskar and colleagues suggest it has to do with changing circulation patterns. There’s a swirling of air high above us — a global circulation that pushes air from the equator up to the poles and back around at lower altitudes. As the solar wind pours into the thermosphere near the poles, the added energy can alter this circulation pattern, driving winds and atmospheric compression that can raise temperatures even far away.

Changing circulation might also underlie another surprise finding. GOLD’s data showed the amount of heat added depended on the time of day. The team discovered a stronger effect in the morning hours compared to that in the afternoon. They suspect that geomagnetic activity might especially strengthen the circulation during the night and early morning hours, though this explanation awaits confirmation in further studies.

Laskar was most impressed with the subtlety of the changes they could detect in GOLD’s data.

“We used to believe that only prominent geomagnetic events could change the thermosphere,” Laskar said. “We are now seeing that even minor activity can have an impact.”

With its steady stream of temperature measurements, GOLD is painting a picture of an upper atmosphere much more sensitive to the magnetic conditions around Earth than previously thought.

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