What is winter like on other planets?

Earth has many seasons mainly due to its tilt and winters are colder, but not all planets in the solar system are like that.

Mercury

With a year lasting just 88 Earth days, all seasons on Mercury are short. However, the lack of air (let alone ocean) to evenly distribute heat results in fluctuating temperatures, making the environment very harsh.

On Earth, seasons occur largely because the Earth's axis is tilted about 23.5 degrees, causing one hemisphere to receive more sunlight than the other at a given time. But this is not true for Mercury, whose axis is tilted only 2 degrees.

Mercury's distance from the Sun varies greatly, from 46 million km to 69 million km. As a result, at its closest point in its orbit, Mercury receives twice as much radiation as at its furthest point. Mercury's true winter occurs when the planet is farthest from the Sun. At that time, noon temperatures at the equator are 150 degrees Celsius lower than when the planet is at its closest point.

The biggest temperature swings, however, are not seasonal. Mercury’s day is 59 Earth days long, so there’s plenty of time to warm up or cool down. Even in winter, it’s very hot in the middle of the day (around 500 degrees Fahrenheit) at the equator, but cold at night, with temperatures dropping to minus 300 degrees Fahrenheit at the equator, and even colder near the poles.

Venus

Venus is so hot that even in the middle of winter and at midnight, the surface temperature does not drop below 438 degrees Celsius.

Mars

Winters on Mars are more like Earth’s than on any other planet. A year on the red planet is almost twice as long as an Earth year, and winters last about four months. Average temperatures on Mars are also much colder. During winter in one hemisphere, the ice cap there grows by capturing about a quarter of the atmosphere (mostly CO2) as dry ice, then shrinks in the spring.

On Earth, the effects of the seasons are moderated by the oceans, which also act as huge reservoirs of heat. In ancient times, this may have been true of Mars, albeit to a different extent. But now that Mars has no oceans, the temperature range is much wider. Mars can get very cold in the winter, with temperatures recorded as low as -153 degrees Celsius, and possibly even lower because many landers and rovers are shut down in the winter due to lack of sunlight to recharge their batteries. This has prevented scientists from recording the coldest temperatures.

The ice cap on Mars may expand in winter. Photo: NASA/JPL/USGS — The ice cap on Mars may expand in winter. Photo: *NASA/JPL/USGS*

Jupiter

Jupiter has no distinct seasons. Its axis is tilted by only 3 degrees, not much more than Mercury's. Jupiter's orbit is also nearly circular, so the amount of sunlight it receives does not vary significantly. Winter here is similar to any other time of year.

Saturn

Saturn's axis is tilted slightly to Earth's, at 26.7 degrees. At times outside the equinoxes, one hemisphere of Saturn receives slightly more sunlight than the other. However, this doesn't change the temperature much. Even in the hot summer, Saturn is too far from the Sun to warm up significantly. The planet's thick atmosphere helps to redistribute much of the heat. In the upper atmosphere, temperatures can drop to -191 degrees Celsius in the winter.

Uranus

Uranus has an axis tilt of 97 degrees. This causes the seasons to differ greatly in sunlight, with one pole facing almost directly towards the Sun in the summer and almost completely away in the winter. As a result, winters here are long and dark. Winters are also very cold, but that's mainly because the entire planet is cold, colder than Neptune, despite being closer to the Sun.

Neptune

At 28.3 degrees, Neptune's axis is tilted more than Earth's. Its orbit is also very circular, so like Earth, the seasons are determined by which hemisphere receives more sunlight. However, the planet receives only about 0.1% of the amount of sunlight that Earth does. Unlike Uranus, Neptune receives significant warmth from its core, but this warmth does not vary with the seasons, so winter cold is not much different from summer cold.

Thu Thao (According to IFL Science )

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