What planet is closest to the sun? The planet that is closest to our Sun is Mercury. It goes around the Sun from a distance of 58 million kilometers (36 million miles). Because it’s so close, Mercury experiences very high temperatures during daytime and extremely low ones at night. Mercury, the smallest planet in our solar system, has a rocky surface like Earth. However, it is not similar to our home because it lacks a decent atmosphere.

Factors Determining a Planet’s Distance from the Sun

What planet is closest to the sun can depend on various factors. The first law of planetary motion, which Johannes Kepler developed in the 1600s, says that planets travel around the Sun in paths shaped like ellipses and the Sun is found at one focus point. The second law, termed as “law of equal areas,” explains how a line connecting any planet to its sun will sweep out equivalent regions during matching time durations.

This shows that planets hasten when they approach nearer to their respective Suns. The third law of Kepler, called the law of periods, explains a mathematical connection between how long it takes for a planet to complete its orbit around the Sun and the cube of that planet’s semi-major axis.

This means that planets which are further from the Sun have longer orbital periods. These laws provided a basis for contemporary astronomy and played a crucial role in Isaac Newton’s creation of universal gravitation’s law. So deciding what planet is closest to the sun can be a complex task.

Mercury’s Unique Characteristics

When we ask what planet is closest to the sun we get mercury. Mercury, having a radius of only 2,440 kilometers, is the smallest planet in our solar system. Because it is close to the Sun with an average distance of 58 million kilometers, there are huge changes in temperature. In the daytime its surface can be scorchingly hot at around 840°F (450°C), but during nighttime it becomes extremely cold and drops down to -290°F (-179°C).

This severe difference happens because Mercury does not possess a big atmosphere to keep warmth. The planet’s slight exosphere, essentially made up of oxygen, sodium, hydrogen, helium and potassium is not thick enough for stopping fast heat escape in long Mercurian nights. The extreme hot and cold temperatures along with no atmosphere make Mercury a tough place to live in.

Dwarf Planets

When we ask what planet is closest to the sun we should also consider the dwarf planets. Pluto is a dwarf planet, which means it revolves around the Sun but has not removed all objects in its orbit. In our solar system, there are five known dwarf planets: Ceres, Pluto itself, Haumea followed by Makemake and finally Eris. These small planets come in different sizes, compositions and how they move around their orbits.

As an example, Ceres, which is the nearest dwarf planet to Earth, orbits at a distance of only 2.8 times Earth’s distance from the Sun. It finishes one year in 4.6 Earth years orbiting around the sun once every 4.6 years.

On the other hand Eris, known as the biggest dwarf planet, maintains its average distance from the Sun at about 68 astronomical units, needing approximately 561.4 earth-years for one complete round around our star.

Implications of a Planet’s Distance from the Sun

When it comes to what planet is closest to the sun there are many implications. The distance between a planet and its star is important for the planet’s warmth, air and ability to support life. The star’s energy radiation, heating from greenhouse gasses along with type of host-star spectral play key roles in shaping planetary climate and chemistry effects.

For example, planets around early M dwarfs could see a decrease in temperature gradient because of clouds forming on the daytime side.

On the other hand, those circling late M dwarfs might have more water vapor to create a greenhouse effect. The radiation coming from stars in the UV range can affect loss of atmosphere, its makeup and habitability of planets.

The effects might be more pronounced on planets around M dwarfs due to these stars emitting a significant amount of XUV emission, including flares. This kind of emission has potential to warm and ionize upper atmospheres on terrestrial planets which would result in more atmospheric loss that could impact habitability.

Observing the Closest Planets to the Sun

We know “what planet is closest to the sun” But the most perfect moments to see Mercury and Venus are at their greatest elongations, when they reach farthest from the Sun in morning or evening skies. It is very simple to observe Venus because it shines quite brightly and can be seen for a long time in the sky.

You are able to observe this planet during daytime as well. When you use telescopes that can be bought at stores, together with cameras available for commercial purchase, viewers may take pictures of phases from Venus or its size changing which will improve their viewing experience greatly.

While observing close to the Sun, it’s very important to not accidentally expose your eyes directly to sunlight. This can harm them. Using solar filters made especially for viewing the Sun is crucial, and observers must wait until the Sun has fully set or risen before trying to view Mercury or Venus.

If you still have doubts regarding “what planet is closest to the sun” you should come back here again. Knowing the order and distances of planets in our solar system is very important for learning about how they were made, changed over time, and their ability to support life. The positions of each planet from the Sun like Mercury that is close enough to get very hot or Neptune which remains in an icy area help define its special features and affect its path as well.