Science-based Q&A

How Many Planets Are In Our Solar System?

There are eight planets in the solar system: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.

Astronomy Questions & Answers

Asteroids: What Are They and Where Do They Come From?

Asteroids are rocky objects leftover from the solar system's formation, found primarily in the asteroid belt, a region of the solar system in between the orbits of Mars and Jupiter.

Comet ISON (C/2012 S1)

Astronomy Questions & Answers

Comets: What Are They? Where Do They Come From?

Comets are suspected to be remnants of planet formation in the solar system about 4.6 billion years ago and primarily originate in the Kuiper Belt and the Oort Cloud.

Science-based Q&A

Why do comets have tails?

Comets develop tails as they approach perihelion—the place in their orbits when they are closest to the sun. The sun’s heat causes some of the material in a comet to vaporize, which in turn releases dust particles that were trapped in the ice.

Astronomy Questions & Answers

How big is the Sun?

The Sun is more than 330,000 times as massive than the Earth. It has a diameter of nearly 1.4 million kilometers (865,000 miles), and its volume could enclose about 1.3 million Earths.

Space weather

Astronomy Questions & Answers

What is the solar wind?

The Sun’s outer atmosphere, the corona, is the source of the solar wind, a steady outflow of charged particles from the Sun.

Eight planets await

Science-based Q&A

What Is the Smallest Planet and Largest Planet in our Solar System?

When it comes to both mass and volume, Jupiter is the largest planet in the solar system, while Mercury is the smallest.

Astronomy Questions & Answers

What is a meteor shower?

Meteor showers occur when Earth passes through a stream of meteoric material. The brief streaks of luminescence we call meteors are caused by meteoroids burning up as they pass through the atmosphere.