Venus rotates slowly in the opposite direction of most planets. Its dense atmosphere induces a runaway greenhouse effect, trapping heat and crowning it the hottest planet in our solar system.
Venus, the second planet from the Sun, is our closest planetary neighbor. While similar in size and
structure to Earth, that is where the resemblance ends. Venus spins slowly in retrograde (opposite
direction) compared to most planets. Its thick, toxic atmosphere traps heat in a runaway greenhouse
effect, creating surface temperatures hot enough to melt lead. Radar mapping reveals a surface dominated
by volcanoes and deformed mountains hidden beneath the clouds.
It is named after the Roman goddess of love and beauty, known as Aphrodite in Greek mythology.
Mariner 2: Mariner 2 was a pioneer in planetary exploration, becoming the first spacecraft to successfully encounter another planet. Launched as a backup after the failure of Mariner 1, its mission was to fly by Venus. Mariner 2 returned critical data on the planet's atmosphere, magnetic field, charged particle environment, and mass, while also measuring the interplanetary medium during its journey.
With a radius of 3,760 miles (6,052 kilometers), Venus is nearly Earth's twin in size, being just
slightly smaller.
Orbiting at an average distance of 67 million miles (108 million kilometers), Venus is 0.7 astronomical
units (AU) from the Sun. One AU is the distance from the Sun to Earth. Sunlight takes about 6 minutes to
travel from the Sun to Venus.
Venus exhibits a unique rotation and orbit. It is one of only two planets (the other being Uranus) that
rotates from east to west. A single rotation takes 243 Earth days—the longest day of any planet, and
effectively longer than its entire year. However, the solar day (sunrise to sunrise) is shorter, taking
117 Earth days because of this retrograde rotation.
Venus completes an orbit around the Sun in 225 Earth days. Its orbit is the most circular of any planet,
lacking the eccentricity of others.
With an axial tilt of just 3 degrees, Venus spins nearly upright and does not experience seasons.
Venus formed approximately 4.5 billion years ago, coalescing from swirling gas and dust to become the second planet from the Sun. As a terrestrial planet, it possesses a central core, a rocky mantle, and a solid crust.
Internally, Venus mirrors Earth. It features an iron core with a radius of approximately 2,000 miles (3,200 kilometers). Above this lies a hot rocky mantle, slowly churning due to internal heat. The surface consists of a thin crust that bulges and shifts, creating volcanoes and tectonic features.
From space, Venus appears bright white due to highly reflective clouds. On the surface, rocks are greyish
like on Earth, but the thick atmosphere filters sunlight, casting everything in an orange glow.
The landscape is dotted with mountains, valleys, and thousands of volcanoes. The highest peak, Maxwell
Montes, rises 20,000 feet (8.8 kilometers), comparable to Mount Everest. The surface is dusty and bakes
at 880 degrees Fahrenheit (471 degrees Celsius).
Volcanic activity likely resurfaced the entire planet 300 to 500 million years ago. Two major highland
regions dominate: Ishtar Terra in the north (size of Australia) and Aphrodite Terra near the equator
(size of South America).
Craters on Venus are all large (over 0.9 miles/1.5 km wide) because small meteoroids burn up in the
dense atmosphere before reaching the ground.
Surface features are almost exclusively named after famous women, both real and mythological. For
instance, a volcanic crater honors Sacajawea, and a deep canyon is named for Diana, the Roman goddess of
the hunt.
Venus' atmosphere is heavy with carbon dioxide and thick clouds of sulfuric acid. This blanket traps
solar heat, maintaining surface temperatures above 880 degrees Fahrenheit (470 degrees Celsius). While
the surface is sweltering, temperatures drop with altitude; around 30 miles up, conditions resemble
Earth's surface.
The atmosphere is dynamic. While the planet rotates slowly, the upper clouds zip around in just four
Earth days, driven by hurricane-force winds (224 mph/360 kph). Lightning flashes through these clouds.
However, at the surface, winds are sluggish, moving at just a few miles per hour.
On the ground, the sky would appear as a hazy overcast, and the immense atmospheric pressure would feel
like being a mile (1.6 kilometers) deep underwater on Earth.
The surface of Venus is likely uninhabitable. The extreme heat overheats spacecraft electronics rapidly,
suggesting no organism could survive there.
However, scientists speculate about life in Venus' distant past. There is also intrigue regarding the
upper cloud layers, where temperatures are more temperate and could potential harbor microbial life.
Venus has no moon.
Venus does not have rings.
Despite having a similarly sized iron core to Earth, Venus possesses a much weaker magnetic field. This is attributed to its very slow rotation, which fails to generate the same dynamo effect found in Earth's core.