How’s the Weather on Mars?
ESA/DLR/FU Berlin, CC BY-SA 3.0 IGO, via Wikimedia Commons
Ever wondered about the weather on Mars? From global dust storms to extreme cold, learn how the Martian climate compares to Earth’s and what it means for future exploration.
When we talk about weather, we usually think of cloudy skies, warm breezes, or unexpected rain showers. On Earth, weather is shaped by oceans, forests, and a thick, breathable atmosphere. But the weather on Mars offers something entirely different. The Red Planet is a barren desert world with razor-thin air, bone-chilling cold, and storms that can engulf the planet!
But it’s not all hostile. Mars’s weather is also surprisingly dynamic, with shifting seasons, winds strong enough to shape dunes, and temperature changes that keep scientists on their toes. And beyond sheer curiosity, understanding Martian weather is critical for future missions and the dream of human colonisation.
In this article, we’ll take a closer look at Mars’s fascinating climate system, including its atmosphere, its day-to-day weather, its dramatic dust storms, and how it all compares to Earth.
What Is Mars’s Atmosphere Like?
Weather begins with the atmosphere. Mars does have one, but it’s 100 times thinner than Earth’s. Instead of being rich in oxygen and nitrogen, it’s mostly carbon dioxide (95%), with small amounts of nitrogen, argon, and trace gases.
This thin atmosphere has several consequences:
- Low Pressure: At the Martian surface, pressure is less than 1% of Earth’s sea level pressure. You couldn’t breathe without a suit, and liquids like water would quickly boil away.
- Little Heat Retention: Because the atmosphere is so thin, it can’t trap heat. Daytime temperatures can be relatively mild, even as high as 20 °C at the planet’s equator at noon, but nights plunge to extremes.
- Limited Greenhouse Effect: Despite the abundance of carbon dioxide, the thin air means Mars doesn’t benefit from a strong greenhouse effect.
The result? A planet that’s cold, dry, and subject to dramatic temperature swings.
What Is the Temperature on Mars?
So exactly how cold is Mars?
- Average temperature: about –63°C (–81°F).
- Daytime highs near the equator: up to 20°C (68°F) on rare occasions.
- Night-time lows: around –100°C (–148°F) or lower.
These swings can occur within a single Martian day, or sol, which lasts 24 hours and 39 minutes.
The polar regions are even more extreme, with winter temperatures dipping below –125°C (–193°F). Here, carbon dioxide actually freezes out of the atmosphere, creating seasonal “dry ice caps”.
Weather on Mars
The Martian Seasons
Thanks to its tilted axis (about 25°, close to Earth’s 23.5°), Mars has seasons much like Earth. However, each season lasts nearly twice as long, because Mars takes 687 Earth days to orbit the Sun. Here’s what you can expect at different times of the martian year:
- Spring: Dust activity picks up, polar caps begin to recede.
- Summer: Warmer temperatures, occasional local storms, and the most favourable time for landers and rovers.
- Autumn: Winds increase, redistributing dust and sand.
- Winter: Extreme cold and buildup of carbon dioxide ice at the poles.
It’s also interesting to note that seasons are uneven because Mars’s orbit is more elliptical than Earth’s. Southern summers are shorter but hotter, while northern winters are longer but milder.
The Winds of Mars
Even with its thin atmosphere, Mars can still whip up some pretty impressive winds. Typical speeds are around 10–20 km/h, but gusts can reach 100 km/h or more. Because the air is so thin, these winds don’t pack the same punch as Earth’s gales, but they’re strong enough to move dust and shape the landscape.
Wind activity has created sand dunes, dust devils, and streak patterns across the Martian surface. In fact, NASA’s rovers have captured footage of mini-tornado-like dust devils spiralling across the ground!
Martian Dust Storms: Mars’s Most Famous Weather
ESA/DLR/FU Berlin, CC BY-SA 3.0 IGO, via Wikimedia Commons
ESA/DLR/FU Berlin, CC BY-SA 3.0 IGO, via Wikimedia CommonsThe most dramatic weather on Mars is its dust storms, which can grow to planetary proportions. These storms are fuelled by sunlight heating the ground, creating rising air currents that lift dust particles. The thin atmosphere allows dust to remain suspended for weeks, spreading across vast distances ranging from local to global coverage:
- Local storms happen frequently, especially in spring and summer.
- Regional storms can cover thousands of kilometres.
- Global storms are rare but spectacular, cloaking the entire planet in a reddish haze.
One such storm in 2018 ended the mission of NASA’s Opportunity rover, which lost contact when sunlight was blocked for weeks. Global storms can also heat the atmosphere by as much as 30°C, showing just how much dust can influence Martian climate.
Clouds and Frost on Mars
Despite its desert-like conditions, Mars does have clouds, however they’re made not of water droplets, but of water ice and sometimes carbon dioxide crystals. These clouds form high in the atmosphere, often creating thin, wispy patterns. Rovers have even captured time-lapse images of drifting clouds reminiscent of cirrus clouds on Earth.
At the surface, frost can form overnight, coating rocks and soil with thin layers of ice. While it quickly sublimates in the morning Sun, these frosty deposits are evidence of water vapour still circulating in the Martian air.
Water and Weather: A Missing Ingredient
On Earth, weather is deeply shaped by the water cycle, including evaporation, clouds, rain, rivers. On Mars, this system is virtually absent. While water ice exists at the poles and beneath the surface, liquid water can’t survive long on the surface due to low pressure.
This absence of a liquid water cycle is one reason Martian weather seems alien. There are no rain showers, thunderstorms, or hurricanes – only dust storms and temperature shifts!
How Does the Weather on Mars Compare to Earth?
| Feature | Earth | Mars |
| Atmosphere | 78% nitrogen, 21% oxygen | 95% carbon dioxide, very thin |
| Average Temperature | 15°C (59°F) | –63°C (–81°F) |
| Pressure | 1 bar | 0.006 bar |
| Weather Systems | Rain, snow, storms, hurricanes | Dust storms, thin clouds, frost |
| Day Length | 24 hours | 24 hours, 39 minutes |
Mars may be Earth-like in some ways (similar day length, axial tilt), but its weather is far harsher and much less forgiving!
Why Studying Martian Weather Matters
Don’t think that understanding Mars’s weather is simply an academic exercise – it has very real implications for our future space exploration:
- Landing Missions: Thin air makes parachutes less effective, and dust storms reduce visibility. Predicting weather helps engineers design safer landings.
- Rovers and Equipment: Dust can coat solar panels, reducing power (as happened with Opportunity). Future missions need dust-resistant technology.
- Human Exploration: Astronauts will face extreme cold, radiation, and potential exposure to dust storms. Habitats will need robust life-support systems.
- Climate History: Studying current weather gives clues to Mars’s past. Evidence suggests Mars once had a thicker atmosphere and flowing water, meaning its weather may have been more Earth-like billions of years ago.
Could Humans Survive Mars’s Weather?
Living on Mars will mean overcoming some pretty serious weather challenges. Protective suits will be essential outdoors, not just for breathing but for withstanding freezing temperatures. Habitats will need insulation and radiation shielding.
Dust will be another obstacle. Fine and pervasive, Martian dust could clog machinery, contaminate habitats, and pose health risks if inhaled. Any potential future colonists may need technology similar to airlocks and dust-repelling suits.
Yet, despite the risks, none of these obstacles are insurmountable. Scientists are already researching how to create self-sustaining habitats, harness local resources, and design equipment resilient enough for Martian conditions.
A World Waiting to Be Explored
NASA/JPL-Caltech/MSSS, Public domain, via Wikimedia Commons
NASA/JPL-Caltech/MSSS, Public domain, via Wikimedia Commons
Mars may not offer us sunny beaches or spring showers, but its weather is a window into the dynamics of an alien world. From planet-wide dust storms to bone-chilling winters, the Martian climate is a constant challenge – and a constant source of fascination.
As we prepare for human missions in the coming decades, understanding and adapting to Mars’s weather will be as important as rocket science itself. The Red Planet is teaching us that “weather” is not just an Earthly concept, but a universal phenomenon shaping worlds across the cosmos.
At OSR, we believe the night sky belongs to everyone. While Mars might be a little too far away for now, you can bring the cosmos closer by naming a star for someone special. Whether you’re fascinated by Mars, stars, or the mysteries of the universe, it’s a gift that always shines bright, whatever the weather!
