What planets are between Earth and the sun?

Earth’s Inner Neighbors: Let’s Talk Mercury and Venus

Ever looked up at the night sky and wondered about our place in the grand scheme of things? Me too! A great starting point is getting to know our immediate planetary neighbors. When we talk about planets chilling between Earth and the Sun, we’re really talking about Mercury and Venus – the inner solar system’s rock stars. Along with Earth and Mars, they’re the “inner” or terrestrial planets, known for their rocky surfaces and their cozy proximity to our star.

The Inner Solar System: Our Neighborhood

Think of the inner solar system as our local planetary hood, a relatively snug zone close to the Sun. It’s home to the terrestrial planets and the asteroid belt, all nestled inside the “frost line.” What’s the frost line? Imagine a point beyond which it’s cold enough for ice to survive. Inside that line, it’s too toasty, so you mostly find silicates and metals making up these planets.

Mercury: Speedy Gonzales of the Solar System

Mercury, named after that swift Roman messenger god, is the Sun’s closest companion. And get this: it’s the runt of the litter, the smallest of the eight planets – just a tad bigger than our own Moon.

• Orbit and Rotation: Mercury’s got a wild orbit, all stretched out like an oval. At its closest to the Sun (perihelion), it’s only 46 million kilometers away. But when it’s furthest (aphelion), it stretches out to 70 million kilometers. A year on Mercury? A blink – just 88 Earth days. But hold on, its rotation is a snail’s pace. A “day” – sunrise to sunrise – lasts a whopping 176 Earth days! Talk about jet lag.
• Surface Conditions: Mercury’s face is pockmarked with craters, like the Moon’s. And because it barely has an atmosphere to hold onto heat, the temperature swings are bonkers. We’re talking a scorching 430°C (800°F) during the day, plummeting to a frigid -180°C (-290°F) at night. Imagine trying to find the perfect outfit for that weather!
• Fun Fact: Here’s a cool tidbit: Mercury is, on average, the closest planet to Earth. Who knew?

Venus: The Hot, Cloudy Mystery

Venus, named after the Roman goddess of love, is the second rock from the Sun. Often called Earth’s “sister,” it’s a similar size and density. Don’t let the “goddess of love” fool you, though…

• Orbit and Rotation: Venus cruises around the Sun at about 108 million kilometers. A year there is 225 Earth days. Now, here’s where it gets weird: Venus spins backward compared to most planets. And it’s slow. A Venusian day? A staggering 243 Earth days. Longer than its year!
• Surface Conditions: Think of Venus as a pressure cooker wrapped in a toxic blanket. Its atmosphere is thick, nasty stuff – mostly carbon dioxide with clouds of sulfuric acid. This creates a runaway greenhouse effect, making Venus the hottest planet, period. Surface temps hover around 462°C (864°F). And the pressure? Imagine being almost a kilometer underwater – that’s what it’s like standing on Venus.
• Fun Fact: Venus is super bright in our sky, second only to the Sun and Moon. You’ve probably seen it as the “morning star” or “evening star.”

Planetary Distances: A Cosmic Ruler

Remember, planets don’t travel in perfect circles. Their orbits are elliptical, meaning the distance between a planet and the Sun changes. Astronomers use “astronomical units” (AU) to measure these vast distances. One AU is the average distance between Earth and the Sun – about 150 million kilometers.

• Mercury’s average distance from the Sun: 0.39 AU
• Venus’s average distance from the Sun: 0.72 AU
• Earth’s distance from the Sun: 1.00 AU

So, there you have it – a peek at Mercury and Venus. These inner planets, while close in cosmic terms, are wildly different worlds. Understanding them helps us appreciate just how special and unique our own little blue marble truly is. Keep looking up!