Scientists determine the size of planets by measuring how big they are compared to the sky. Through this method, they found out that Pluto is not the smallest.

What Is the Smallest Planet in the Universe?

The result showed that Mercury is the smallest planet in our solar system and can help with physics. With a radius of 1,516 miles, the planet is roughly one-third the width of Earth. The moon's radius is slightly more than 1,000 miles.

According to BBC Science Focus, to calculate the size of the planet, the angular diameter is multiplied by its distance based on its orbit around the sun.

On the other hand, according to USA Today, Mars is the second-smallest planet, with a radius of 2,106 miles. It is almost half the size of Earth. The third planet is Venus, which is only slightly smaller than Earth.

Because Pluto is classified as a dwarf planet, Mercury is still considered the smallest planet, even though it is larger than Pluto. The latter was declared unfit to be a planet by the International Astronomical Union in 2006 because it does not clear its orbital path like the other planets.

What Are the Planet Sizes in Order?

According to NASA, Jupiter is the largest planet as it is 11 times the size of Earth, while the smallest on the list is Venus. Here's a list of planet sizes in order of radius. In this list, we do not include the dwarf planet Pluto.

  • Jupiter (43,441 miles)
  • Saturn (36,184 miles)
  • Uranus (15,759 miles)
  • Neptune (15,299 miles)
  • Earth (3,959 miles)
  • Venus (3,760 miles)
  • Mars (2,106 miles)
  • Mercury (1,516 miles)

ALSO READ: Pluto is Covered In Huge Red Patches; Scientists Don't Know What It Is

What Is Planet Mercury Known For?

Mercury is not only the smallest but also the closest planet to the sun. According to NASA, it is nearly 36 million miles (57.9 million kilometers) from the sun.

While the planet is closest to the sun, Venus is the hottest planet in our solar system. Its surface temperature is 900 degrees Fahrenheit. On the other hand, Mercury still has a maximum temperature of 800 degrees during the day, but temperatures can drop to -290 degrees due to the planet's lack of atmosphere.

The Sun appears to rise briefly, set, and rise again from some parts of Mercury's surface due to its elliptical egg-shaped orbit and slow rotation, NASA said. The same thing happens in reverse during sunset.

It is the fastest planet in our solar system. It moves through space at nearly 29 miles per second (47 kilometers per second). Keep in mind that the faster a planet moves, the closer it gets to the Sun. Mercury also has the shortest year of any planet in our solar system because it travels the shortest distance around the Sun.

The planet's exosphere primarily comprises oxygen, sodium, hydrogen, helium, and potassium. It is unlikely to survive on Mercury due to solar radiation and extreme temperatures.

Two NASA missions, Mariner 10 and MESSENGER, have explored the planet. The European Space Agency's BepiColombo spacecraft is on its way to Mercury.

RELATED ARTICLE: Pluto Demotion to Dwarf Planet Rooted in Folklore? Scientists Want to Reinstate It, Make Moons As New Planet

Check out more news and information on Space in Science Times.