Incredible Photos Show Saturn at Its Closest to Earth in 2021

The planet Saturn put on a show for Earth this week as the gas giant appeared at its closest and brightest for the year in the early hours of Monday EDT.

The event prompted a number of backyard photographers to get out their telescopes and capture a shot of the ringed world as it moved across the sky.

A number of the photos can be seen below, clearly showing the distant planet and its trademark rings.

Saturn was particularly bright on Monday because it appeared opposite the sun from Earth's perspective—a phenomenon known as opposition.

Gordon Johnston, a retired NASA executive who writes monthly articles on skywatching opportunities, referred to Saturn's opposition as "effectively a 'full Saturn'."

Another way of looking at planetary opposition is to think of it as the moment when the Earth comes between a certain planet and the sun.

Oppositions are important for astrophotographers because they present a great opportunity to get a photograph of a planet in the sky. Planets in opposition appear to be bigger and brighter than they normally do.

Opposition is also useful for trying to spot fainter objects in the solar system such as asteroids.

Only objects that orbit the sun further out than the Earth does can be in opposition, so Venus and Mercury cannot be.

Because the Earth passes around the sun once per year, planetary oppositions for Jupiter, Saturn, Uranus and Neptune usually occur annually. An opposition of Mars happens less often; around once every 27 months, according to the U.K.'s Royal Museums Greenwich.

Saturn is a beautiful world to photograph because of the large rings that circle the entire planet. The rings of Saturn are thought to be made of billions of chunks of ice, rock and dust, as well as the remnants of comets, asteroids or even moons that were torn apart by the vast planet's gravitational force.

The rings are also incredibly thin compared to their diameter. The ring system extends up to 175,000 miles above Saturn, yet the main rings are generally only about 30 feet in terms of thickness, according to NASA.

While the rings may appear to be one single ring when seen from Earth, there are actually several and they orbit at different speeds.

Saturn itself is made out of gas, as are all the planets of the solar system further out than Mars. It is made mostly of hydrogen and helium, though the planet has a dense core made out of metal and rock.

For those who missed the chance to photograph Saturn at opposition, Jupiter will also appear at opposition this month on August 19.