What is Venus Made Of?

Earth’s closest neighbor and the second planet from the Sun is Venus. Venus is an inner, terrestrial planet, which means Venus is made of rocky ground.

It is similar in size and density to Earth and sometimes called Earth’s twin because of its size similarities. Like Earth, Venus likely has a rocky mantle and semi-liquid core. But the remaining differences between the two planets are radical.

Let’s delve into what Venus is made of and any other Venus questions you might have!

What is Venus’ Atmosphosphere Made of?

The atmosphere of Venus is made of super-dense carbon dioxide. So saying it’s a toxic planet is an enormous understatement. The atmosphere is nearly 90 times as thick as Earth’s, with almost no water vapor. That’s about the same amount of pressure you’d feel about a mile beneath an ocean’s surface. 

In addition, thick sulfuric acid clouds storm Venus’ atmosphere trapping heat and creating a rotten-egg-smelling runaway greenhouse effect. These smelly clouds are about 28 miles above Venus’ surface, rising to 43 miles (45-70 kilometers.)

Venus’ toxic clouds whip around so quickly that they circle the planet every four and a half days at about 200 miles per hour.

Why is Venus So Hot?

Mercury is the nearest planet to the Sun, but Venus takes first place as the hottest planet. And it’s a hellish world where surface temperatures reach 864℉ (462℃.) If you’re wondering just how hot that is, Venus is hot enough to melt lead.

The greenhouse effect is what makes Venus so hot. And here’s how it works. 

Scientists think Venus and Earth formed in similar fashions, with similar rocky ingredients. But Venus took a drastically different path than our home planet did. 

Venus’ Runaway Greenhouse Effect

NASA’s 1980s Pioneer mission to Venus took measurements suggesting Venus had an ocean at one time. However, scientists think the ocean waters evaporated because of the planet’s closer proximity to the Sun.

Then the Sun’s ultraviolet radiation broke apart the water vapor molecules, causing hydrogen to escape into space. Once no surface water remained, the atmosphere filled with carbon dioxide. And that’s what caused the runaway greenhouse effect.

Venus’ Surface

Thousands of volcanoes and scrunched-up mountains cover Venus’ rusty-colored surface. Some volcanoes are likely still active.

Venus’ Surface
Venus 45-Mile-Wide Surface Crater: NASA/SpacePlace

What is the Surface of Venus Made Of?

Venus’s surface is made of dome-like volcanoes, plains, mountains, and ridged plateaus. The surface is youthful compared to the planet’s age.

Scientists think Venus’ surface could only be about 150 million years old and younger than a billion years. However, even though they can tell the planet’s surface is geologically young, they don’t know what happened to cause the planet’s resurfacing.

One of the most significant differences between Earth’s surface and that of Venus is that Earth has plate tectonics. And Venus has no evidence of them.

What is the Inside of Venus Made Of?

While scientists don’t know precisely what the core of Venus is made of, they believe it is similar to Earth’s core. Venus’ core radius is approximately 1864 miles (3000 km.) And it primarily consists of iron (80%), nickel (6%), sulfur, and a tiny amount of oxygen.

What Was Venus Made of When It Was Formed?

When Venus first formed, computer modeling of its ancient climate showed that it likely did have the liquid water ocean that the Pioneer’s measurements pointed toward.

In 2016, Goddard Institute for Space Studies (GISS) scientists believed Venus likely had more dry land than Earth. In addition, Venus’ vast tropical areas limited water evaporation from the oceans and created a surface that appeared ideal to support abundant life.

In addition, the modeling simulated an Earth-like atmosphere on the hypothetical ancient Venus. It also factored in Venus’ long days and Pioneer’s ocean measurement data. Next, the scientists added 1990s Magellan radar measurements to approximate the planet’s surface topography. And finally, they added in the Sun’s radiation.

The ancient Sun was 30% dimmer than our current version. But Venus’ closer proximity meant the planet still got 40% more sunlight than we do today.

The GISS scientists found that because of the planet’s slow rotation, the Sun warmed Venus’ surface for about two months at a time on its dayside. The warm surface created rain and a thick cloud band. And the clouds then acted like a sun shield, keeping climate temperatures slightly cooler than Earth’s.

So for about 2 billion years, scientists think Venus could have been hospitable enough to support life. But, ultimately, Venus’s proximity to the Sun removed that possibility. 

Interesting Facts About Venus

Here are some exciting facts beyond what Venus is made of.

How Big is Venus?

Venus has a diameter of about 7,520 miles (12,100 kilometers), similar to Earth’s size. For comparison, let’s say the Sun is the size of your front door. That would make Venus and Earth nickel-sized.

How Many Moons Does Venus Have?

Of the two hundred and fourteen moons in our solar system, Venus has precisely zero of those moons.  

How Far Is Venus From the Sun?

Venus orbits about 67 million miles (108 million km) from the Sun.

What Does Venus Look Like?

Venus’s rocky surface stays hot, even on its night side. The extreme heat makes Venus glow, similar to what a piece of iron looks like when you pull it from a forge.

Magellan Venus Image: NASA Magellan Team/JPL/USGS

Have Any Spacecrafts Explored Venus?

Yes, Venus is a spacecraft magnet! It was the first planet that our spacecraft explored and studied. It’s also the first planet where probes made it to the surface, even though they only survived briefly before burning up.

Some of the Venus missions include

  • NASA’s Mariner 2 flyby scan, December 14, 1962
  • NASA Magellan radar surface mapping and imaging, 1989-1994
  • Soviet surface probe missions
  • NASA’s Pioneer surface probe missions, 1978
  • ESA’s Venus Express, 2006-2016
  • Japan’s Akatsuki Venus Climate Orbiter 2016-present
  • NASA’s Parker Solar Probe flyby imaging, 2020
What is Venus Made Of?
Wide-field Imager for Parker Solar Probe (WISPR) Venus image: NASA/APL/NRL

Are Any Missions to Venus Coming Up?

Three Venus missions are upcoming. 

  • NASA’s Venus Emissivity, Radio Science, InSAR, Topography, and Spectroscopy (VERITAS) mission launches around December 2027. Its mission is to gather data about how Earth and Venus took separate paths, causing Venus to lose its life-supporting potential. 
  • NASA’s DAVINCI late 2020s mission will drop surface probes on Venus to measure and image its surface.
  • ESA’s EnVision will also observe Venus and take high-resolution surface feature measurements.

Can Life Exist on Venus?

In Venus’ current condition, life, as we know it, could not likely exist. However, phosphine is a possible microbial life indicator. And it has been observed high in the cooler, lower-pressure clouds. So perhaps microbes live, but there is no current proof of that theory.

Does Venus Spin Backwards Compared to Earth?

Venus rotates backward on its axis, which is opposite to Earth. So the Sun rises in the West, backward to our experience.

Summary: What is Venus Made Of?

Venus is a fascinating world made of mountains, volcanos, and plateaus. With a metallic core similar to Earth’s, the planet formed from iron, nickel, sulfur, and oxygen. However, it’s cloudy and poisonous atmosphere is very different from ours.

The runaway greenhouse effect on Venus creates a thick atmosphere that traps in solar heat. At the same time the clouds reflect sunlight making the planet the second brightest night sky object (after the Sun.)