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Hottest Planets in the Universe: Best Online Guide

In this article, you will learn about Venus, Mercury, WASP-12b, and KELT-9b. All of these planets are remarkably hot! But which planet is really the hottest? You might be surprised to learn that Venus is the most hot of all! Here are five of the hottest planets in the universe. They all have different temperatures! And the hotter ones are much more interesting.


The atmosphere of Venus is more than 100 times bigger than that of Earth, and the surface of the planet is therefore very hot. Since most of this heat cannot escape into space, it builds up to extremely high temperatures. This process is known as the greenhouse effect, and Venus’ surface temperature reaches 864 degrees Fahrenheit. The heat on Venus’ surface is a direct result of this intense greenhouse effect. This phenomenon makes Venus the hottest planet in the universe.

Earth and Venus are often considered twins, and this is because they are nearly the same size and mass. They are also similar in composition and gravity. The mass of Venus is around eighty percent of Earth’s, and its interior consists of a metallic iron core that is about two and a half miles across. The molten rocky mantle is about a thousand miles thick. Venus’ crust is six to twelve miles thick and is made primarily of basalt.

Several missions have been launched to Venus to explore the planet’s atmosphere. The ESA’s Venus Express mission orbited the planet from 2006 until 2016. Japan’s Akatsuki Venus Climate Orbiter is currently in orbit. The space agency also recently funded a balloon mission to Venus. And the NASA-led Parker Solar Probe has made multiple flybys of Venus and recently captured the first images of Venus from space. Another mission, EnVision, is detailed. NASA is one of its key partners in the project, providing the Synthetic Aperture Radar (SAR), which will gather high-resolution measurements.

Magellan also found no evidence of plate tectonics on Venus. This means that Venus’ rocky interior does not move, and heat escapes through volcanoes. Unlike Earth, Venus has no moon and no rings. Magellan’s findings led scientists to believe that the interior of Venus is similar to Earth. Because plate tectonics are absent on Venus, the craters on Venus do not function like those of Earth.


The smallest planet in the solar system, Mercury experiences extreme temperatures on a daily basis. The daytime temperature on Mercury can reach more than 430 degrees Fahrenheit, while nighttime temperatures are only around -180 degrees. This extreme difference between daytime and nighttime temperatures makes life on Mercury impossible. Nevertheless, Mercury is one of the most fascinating planets in the universe, and there are many questions still to be answered.

Although Mercury has a thin, non-protective atmosphere, its surface is largely devoid of atmosphere. Mercury’s exosphere is composed of atoms blasted off Mercury’s surface by solar wind. These atoms are then carried high into space by solar winds. This means that Mercury is constantly losing its atmospheric atoms to space. The higher the temperature, the more outgassing Mercury experiences.

The slow rotation of Mercury causes its surface to vary in temperature. In fact, a single sunrise on Mercury would be unusual on Earth. Because Mercury spins nearly vertically on its axis, the poles of the planet are never completely exposed to the sun. Additionally, it does not experience yearly seasons, and its atmosphere is small. It is made up mostly of oxygen, sodium, hydrogen, and helium.

While Mercury is the hottest planet in the universe, Venus is the second hottest planet in the solar system. It has a temperature of 462 degrees Celsius. This difference is due to the fact that Venus has a thick layer of clouds that prevent heat from escaping into outer space. Moreover, Venus has a much smaller atmosphere than Mercury, which means that the surface of the planet stays cooler than Mercury’s at any given time.


A transiting exoplanet, WASP-12b, is the hottest planet in the universe, according to astronomers. The planet, which orbits a star 870 light years from Earth, has a daytime temperature of 2,700 K or 4,400 degrees Fahrenheit. Its surface is prolate, and it is losing mass at the rate of about 1 Earth mass every 30,000 years. Scientists think that the planet may have only about ten million years left to be eaten by its parent star.

The hottest planet in the universe was discovered by scientists in 2009. The research team from the SuperWASP project in the UK, Spain and South Africa, used a telescope to detect WASP-12b. The planet was discovered by observing the dip in brightness in the parent star. The observations allowed researchers to determine the size of the planet and its mass. The planet’s temperature could also be deduced by estimating the distance from the star.

In addition to its extreme heat, WASP-12b also has a low albedo. Its surface is blacker than fresh asphalt, and 94 percent of the light falling on it is absorbed by the atmosphere. The Hubble Space Telescope’s spectrograph measured the planet’s albedo, a measurement of how much light a planet reflects. WASP-12b has an albedo of 0.064 – which is compared to Earth’s moon, which has an albedo of 0.12. Clouds are believed to prevent light from escaping a planet. However, this explanation is not valid for WASP-12b because it is too hot to be able to form clouds.

WASP-12b orbits a star at an incredible distance of just 0.022 AU, making it the hottest planet in the universe. Its daytime side is hot, but its nightside is cooler. The dayside temperature on WASP-12b is just under 2,200 degrees Fahrenheit. Scientists have found water on WASP-12b, which is part of a class of exoplanets known as “hot Jupiters”.


The fifth planet from the Sun, Jupiter, is the largest planet in our Solar System and a gas giant, with a mass more than 2.5 times larger than all the other planets combined. Yet, Jupiter only has a mass one-thousandth that of the Sun. That’s because of its huge size: the surface of Jupiter is over five billion degrees Fahrenheit warmer than the surface of the Sun.

The dayside temperature of KELT-9b is around 4,600 K, much warmer than the surface of many low-mass stars. This means that the atmosphere of KELT-9b is so hot that molecules break down into their component atoms. This allows otherwise sequestered refractory elements to exist as atomic species. Researchers have measured the presence of metal oxides and hydrides in the planetary atmosphere, which could lead to the emergence of a planetary atmosphere with a temperature of ten thousand or eleven thousand K.

While hot Jupiters were the first exoplanets discovered, KELT-9b is the hottest known planet. It orbits a star approximately six hundred and sixty light years from earth. Because of its extreme heat, Kelt-9b is considered an extrasolar planet. It is also the closest planet to our sun, and it is in our star’s habitable zone, a distance of about six hundred light years.

Despite its high dayside temperature, KELT-9b is only 2.8 times as massive as Jupiter and half as dense. This planetary atmosphere is inflated by extreme radiation, which could unravel its atmosphere. This, in turn, causes its extreme evaporation of water and is responsible for the planet’s extreme heat. It has a surface temperature of 7,800 degrees Fahrenheit.


A giant rocky planet, Kepler-10b, orbits its parent star once every 0.84 days and is at least twice as big as Mercury. It is about 20 times as massive as Earth, and scientists call it a “mega-Earth.” This planet could have a similar temperature to Earth, and could be cool enough to support life. According to dimitar sasselov, director of the Harvard Origins of Life Initiative, Kepler-10b may have a stable atmosphere.

The hotter planet in the universe is Kepler-10b. The rocky planet has a surface temperature of 2,500 degrees. Scientists have long suspected that Kepler-10b was an extraterrestrial planet. The discovery has raised hopes for further planetary discoveries. Kepler-10b is also the smallest planet outside the solar system. Its mass makes it one of the most densely packed planets known.

In addition to being the hottest planet in the universe, Kepler-10b orbits its parent star very close to our own sun. The planet is so close that it has a surface temperature of 2,500 degrees. Scientists believe that parts of the planet’s surface may be molten. There is also a possibility that sun-seared flecks of Pluto may trail behind it like comets.

The planetary science community has long suspected Kepler-10b as the hottest planet in the universe. Since Kepler-based telescopes were launched in 2009, it’s been an interesting search for new planets. Among them is Kepler-10b, a planet with an ionizing temperature of 230 degrees Celsius. It is 2.6 times the size of Earth, but is only one-third as dense. As such, it must have a large amount of water. Eventually, the planet could have a liquid-water ocean.