Space

Animation: Using Planets to Visualize the Speed of Light

Published

3 years ago

February 1, 2022

James O’Donoghue

Featured Creator

Article/Editing:

Govind Bhutada

The Speed of Light Visualized Using Planets

We often come across the term “light-year” in the context of space travel. But what does it actually mean?

A light-year is the distance light travels in one year. At a speed of 186,000 miles/sec (300,000km/sec), light travels 5.88 trillion miles (9.46 trillion km) in a year—a distance well beyond immediate comprehension.

Scientists created the term light-year to measure astronomical distances beyond the confines of the Earth. And in the vastness of space, light photons, which can go around the Earth 7.5 times in just one second, seem slow.

The above animation from planetary scientist Dr.James O’Donoghue helps put the speed of light into a broader perspective while highlighting the vast distances between celestial bodies.

Light Speed: Fast, but Slow

The Moon is the nearest celestial body to Earth at 239,000 miles (384,400 km) away. A light photon emitted from Earth would get to the Moon in a mere 1.25 seconds.

But how does this compare to other celestial bodies in our solar system?

Celestial Body	Distance at Closest Approach	Light Travel Time from Earth
Moon	0.38 million km	1.25 sec
Mars	54.6 million km	3 min
Sun	150 million km	8 min
Jupiter	588 million km	33 min
Saturn	1.2 billion km	67 min
Pluto	4.3 billion km	4 hrs

If you watched the entire length of the above video, you probably saw how “slow” light is. The same photon of light that reached the Moon in a little over a second took three long minutes to reach Mars, the next planet beyond Earth in our solar system.

It takes light just over eight minutes to get from the Sun to Earth. This means that when we look at the Sun, we see it as it was eight minutes ago, and if it were to disappear suddenly, we wouldn’t realize it for eight whole minutes.

Therefore, how “fast” or “slow” light is depends on your perspective. To us Earth-dwelling humans, it feels instantaneous. But the vastness of the universe makes even light seem slow—and it travels at a speed that our spacecraft aren’t even close to matching.

This article was published as a part of Visual Capitalist's Creator Program, which features data-driven visuals from some of our favorite Creators around the world.

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Space

What Resources Can We Get from the Moon?

While solar energy is abundant, mineral and water extraction technologies are still developing.

Published

1 month ago

March 23, 2025

Bruno Venditti

This graphic highlights the resources identified on the Moon’s surface.

What Resources Can We Get from the Moon?

This was originally posted on our Voronoi app. Download the app for free on iOS or Android and discover incredible data-driven charts from a variety of trusted sources.

The idea of mining the Moon, once a concept of science fiction, is now approaching reality. According to Yury Borisov, head of Russia’s space agency Roscosmos, the race to explore and develop the Moon’s resources has begun.

This graphic highlights the resources identified on the Moon’s surface, based on data from the U.S. Geological Survey as of 2022.

Key Resources on the Moon

The Moon is almost entirely covered by regolith, a layer of pulverized rock that could serve as a versatile construction material. It has potential applications in building bases, landing pads, and roads.

Additionally, NASA is developing technology to process at least 15 metric tons of ice from the lunar south pole by 2030, aiming to produce at least 10 metric tons of oxygen and 2 metric tons of hydrogen. Radar signals suggest the presence of ice in numerous polar craters and surrounding areas. These resources could be crucial for sustaining life and fueling rockets.

Moon resources	Current classification	Recoverable with current technology	Plausible reserve in 30 years
Solar energy	Measured reserve	Yes	Yes
Helium-3 ³He	Inferred unrecoverable resource	No	Unknown
Bulk regolith	Measured unrecoverable resource	No	Yes
Regolith oxygen	Measured unrecoverable resource	No	Yes
Bound water and hydrogen	Inferred unrecoverable resource	No	Probably
Water ice	Minimal or no evidence	No	Unknown

Hydrogen could also be used to generate water, though it is relatively scarce on the Moon. Extracting just one liter of water would require processing approximately 100 truckloads of regolith.

Among the Moon’s most abundant resources is solar energy. The technology to harness it is well-developed, with its first successful use on the lunar surface achieved in 1966 by the Soviet Union’s Luna 9 mission.

How Close Are We to Utilizing Lunar Resources?

While solar energy is readily available, technologies for extracting minerals and water from the Moon are still in development. However, progress is being made by various national space agencies, including NASA, Roscosmos, the European Space Agency, the China National Space Administration, the Israel Space Agency, and the Indian Space Research Organization. Several commercial ventures are also working to advance lunar resource extraction.