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How does Earth look from outer space?

A tiny Earth, and a barely visible orbiting moon, seen from Mars.
So tiny! A spacecraft orbiting the world next door, Mars, captured this sequence of 4 images showing the moon in orbit around Earth on June 2, 2023. The Mars Express spacecraft usually looks down at Mars. But it turned its gaze earthward in celebration of the 20-year anniversary of its launch. Image via ESA.

What does Earth look like from outer space? And … how far away from Earth can we be and see it still with our own eyes?

To find the answer to these questions, let’s take an imaginary trip through the solar system. Indeed, spacecraft exploring our solar system have given us marvelous views of Earth. Keep reading, and check out the photos on this page, to see how Earth looks from various other places in our own neighborhood of space.

The view from orbiting the Earth

First, imagine blasting off and being about 200 miles (300 km) above Earth’s surface. That’s about the height of the orbit of the International Space Station (ISS). From the window of the ISS, the surface of the Earth looms large. Indeed, in the daytime, you can clearly see major landforms. Subsequently, at night, from Earth orbit, you see the lights of Earth’s cities.

Curve of Earth, with clouded areas and 3 large, shiny flat patches, the lakes.
Earth in daylight, from the International Space Station in 2012. The North American Great Lakes shine in the sun. Image via NASA.
Black night orbital view of planet Earth centered on Sweden with gold lights of cities and green aurora.
Astronauts onboard the ISS took this glorious view of northern Europe and the aurora centered on Sweden. Image via NASA.

From the moon

Now, let’s get farther away, say, the distance of the orbit of the moon.

As we pass the moon – some quarter million miles (about 380,000 km) away – Earth looks like a bright ball in space. In fact, it’s not terribly different from the way the moon looks to us.

Significantly, the first images of the Earth from the moon came from the Apollo mission. Apollo 8 in 1968 was the first human spaceflight to leave Earth orbit. Likewise, it was the first earthly spacecraft to be captured by and escape from the gravitational field of another celestial body, in this case the moon.

It was, therefore, the first voyage in which humans visited another world and returned to Earth.

The moon's surface below Earth, seen as a half of green-blue sphere floating in blackness above.
Earth captured from the moon by Apollo 8 astronauts in 1968. Image via NASA.

In the decades since Voyager first began traveling outward, moon exploration has become more common. For example, the Korea Aerospace Research Institute (KARI) just recently released a set of black-and-white images of the Earth and moon. The Korea Pathfinder Lunar Orbiter – also known as KPLO or Danuri (moon enjoy) – captured the image below sometime after it entered lunar orbit on December 26, 2022.

Black and white photo of full Earth beyond dim, gray cratered surface in the foreground.
A fully illuminated Earth rises over the darkened horizon of the moon in this image from the Korea Pathfinder Lunar Orbiter (KPLO or Danuri). Image via KARI.

Earth and moon together

Now, let’s keep moving outward until we can see both the Earth and moon together in space.

Since 1977, many robot spacecraft have ventured outward into our solar system. The image below of Earth and the moon was acquired by the multispectral imager on the Near Earth Asteroid Rendezvous Spacecraft (NEAR) on January 23, 1998. It was recorded 19 hours after the spacecraft swung by Earth on its way to the asteroid 433 Eros. The images of both were taken from a range of 250,000 miles (400,000 km), approximately the same as the distance between the two bodies.

Crescent moon and slightly more than half Earth against black background.
Earth and moon seen by the NEAR spacecraft in 1998. Image via NASA.

Below is a recent view of the Earth and the moon captured by the Orion spacecraft on November 28, 2022.

Sunlit front end of space capsule labeled NASA, with tiny Earth and moon in background.
On November 28, 2022, the uncrewed Orion spacecraft reached its maximum distance – 268,563 miles (432,210 km) – from the Earth and moon. At that point, Orion had traveled farther than any other spacecraft built for humans, and farther than any Apollo mission some 50 years ago. See the moon and Earth in the upper right? Image via NASA.

The next picture was mind-blowing when first released. It shows a crescent-shaped Earth and moon – the first of its kind ever taken by a spacecraft – on September 18, 1977.

Small brownish gray crescent above larger green and white crescent.
This picture of a crescent-shaped Earth and moon – 1st of its kind ever taken by a spacecraft – was recorded September 18, 1977, by Voyager 1 at a distance of 7.25 million miles (11.66 million km) from Earth. Here, the moon is at the top of the picture and beyond the Earth as viewed by Voyager. Image via NASA.

From a sun-orbiting spacecraft

Three starry points labeled Venus, Earth and Mars against moving field of stars.
Venus, Earth, and Mars on November 18, 2020, as seen via the NASA-ESA Solar Orbiter (SolO). This image was captured from about 155.7 million miles (250.6 million km) away. That’s in contrast to our sun’s distance from Earth of about 93 million miles (150 million km). In this image, the sun is located on the right, outside the image frame. Image via ESA/ NASA/ NRL/ Solar Orbiter/ SolOHI.

The view from the outer planets

Finally, speeding outward from the Earth and moon system, you pass the orbits of the planets Mars, Jupiter and Saturn. Indeed, from all of these worlds, Earth looks like a star, which gets fainter as you get farther away.

Dark landscape, greenish sky with tiny dot, and inset showing 2 dots labeled Earth and moon.
Earth and moon, as seen from Mars by NASA’s Curiosity rover on January 31, 2014. Image via JPL/ NASA.
Saturn and its rings. Labeled Mars, Venus, Earth and our moon at background (they are not actually visible).
View larger | On July 19, 2013, in an event celebrated the world over, NASA’s Cassini spacecraft slipped into Saturn’s shadow and turned to image the planet, seven of its moons, its inner rings, and, in the background, Mars, Venus and our home planet, Earth. See an annotated image here. Image credit: NASA/ JPL-Caltech/ SSI.
Dim, fuzzy vertical green and brown stripes with tiny dot in one of them.
This is the famous image known as Pale Blue Dot. It’s a photograph of Earth taken on February 14, 1990, by the Voyager 1 space probe from a record distance of about 6 billion kilometers (3.7 billion miles). Earth is the bluish-white speck approximately halfway down the brown band to the right. Image via NASA.

I’ve never seen any image of Earth from Uranus or Neptune or any other body beyond Saturn’s orbit. To be sure, only five spacecraft from Earth – the two Voyager spacecraft, the two Pioneers, and the New Horizons spacecraft, which passed Pluto in 2015 – have ever ventured that far. Those craft weren’t designed to look back at Earth, and, to my knowledge, they didn’t capture images of Earth from distances beyond Saturn.

And from farther still?

But, speaking theoretically now, could Earth be seen from distances beyond Saturn?

Specifically, speaking only in terms of Earth’s brightness, the answer is yes. Our world doesn’t become too faint to see with the eye alone until far beyond Neptune’s orbit, at around 9 billion miles (14 billion km) from home. Now, consider Pluto’s orbit. It’s highly elliptical, stretching from just 2.7 billion miles (4.4 billion km) to over 4.5 billion miles (7.3 billion km) from the sun. Overall, Pluto is within the limiting distance at which – if we just consider brightness alone, no other factors – we should be able to see Earth with the eye alone.

But there is another factor. As you go outward from Earth, our world appears closer and closer to the blazing sun. As you get farther away, the sun’s glare begins to overwhelm the view of Earth. From Pluto – even though Earth would be bright enough to see – you probably couldn’t see it in the sun’s glare.

So how far away could you see Earth?

What is the answer to the question of how far you could be from Earth, and still see it with your own eyes? Although no one knows for sure because no one has tried it (and because human eyesight varies from person to person), the Earth would become impossible to see with the eye somewhere beyond Saturn’s orbit.

But now, let’s change the game. Let’s say we could use instruments, and not just the eye alone. And, suppose intrepid astronaut-astronomers went to Pluto. Suppose they took all the instruments they needed to view Earth in the sun’s glare. Could they use telescopes, obscuring disks and other techniques to get a glimpse of Earth? Maybe!

It still wouldn’t be easy, however.

Read more: Wikipedia has a long write-up on extraterrestrial skies

Bottom line: How does Earth look from space? How far away in space could you view Earth with the eye alone? Considering only brightness, the answer is about 9 billion miles (14 billion km) away, about the distance of Neptune or Pluto. In practice, though, seeing it from that distance would be a challenge because the sun’s glare would overwhelm the view of Earth.

The post How does Earth look from outer space? first appeared on EarthSky.

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