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What Are Blue Planets?

What Are Blue Planets?

The blue color is so rare in our solar system, that astronomers were surprised to discover it beyond our own. They studied the color of HD 189733b, a blazing hot gas giant located in the northern constellation Vulpecula. The reason is not fully understood, but researchers believe the blazing hot gas giant is responsible for the planet’s unique blue color. If you’re curious about the color of this planet, keep reading.

Cobalt blue planets

Astronomers have discovered an alien world that shines a deep cobalt blue. Using the Hubble Space Telescope, they have determined the true colour of the distant world. Their findings suggest that this planet may have been a hot Jupiter that could have cooled its surface with sideways rain. Despite its unusual colour, this planet is still relatively small and would have a surface temperature of more than 1100 degrees Celsius.

The cobalt blue colouration of the cobalt blue planet is due to the scattering of blue light within the atmosphere of the distant world. Earth’s atmosphere is composed of silicate particles that are blown around by winds of over 7,000 kph, which is why the planet appears blue to us. Furthermore, the cobalt blue color of this planet could help us determine if it is habitable.

The atmospheric temperature of HD 189733b reportedly allows it to be a cobalt-blue planet. In fact, this planet has no oceans, so the blue colour it exhibits is not due to tropical waters or blow-torched atmospheres. Instead, it is caused by a combination of volcanic activity and molten-silicate rain. As it orbits so close to its star, its atmosphere has a thick layer of silicates, which scatter blue light more than red.

Methane gas

The blue hue on the surface of the planets is caused by methane gas in their atmosphere. Although the atmosphere of these planets is largely made up of hydrogen and helium, methane makes up a small portion of their atmosphere. This gas absorbs red light from the sun and reflects it back into space, giving these planets their blue color. The blue planets are more likely to be icy, which means they have higher concentrations of methane gas than their neighbors.

The methane gas on the surface of Earth is found in concentrations ranging from zero to 35 parts per billion by volume (ppbv), but the planetary average is about 10 ppbv. During a visit to the Blue Planets, scientists measured the amount of methane using the Canada-France-Hawaii Telescope. Unfortunately, they were unable to detect the methane variation across the planet due to poor spatial resolution and signal strength.

In addition to methane, the atmosphere of the Blue Planets contains other gases as well. On Neptune, for example, methane clouds are believed to form in the highest layers of the planet’s atmosphere, due to its frigid temperatures. Methane clouds on the surface of Neptune may contain traces of water, ammonia, or hydrogen sulfide, depending on the region of the planet.

Titan’s thick nitrogen atmosphere is maintained in part by methane. It is also the source of hydrocarbon hazes, which absorb solar infrared rays and warm the stratosphere and troposphere by about 100 degrees Celsius. Without methane, Titan’s atmosphere would collapse, transforming the planet’s unique character. This would also make its surface visible to telescopes from Earth.

Hazy atmosphere

The Hazy atmosphere of Blue Planets are the result of chemical reactions between ultraviolet rays from the sun and gases in the air of Titan. The haze on Titan is orange and similar to Earth’s smog. Chemical reactions in the atmosphere of Titan trigger complex organic molecules. Images of the surface of Triton, a moon of Jupiter, were also captured by Voyager 2 spacecraft. Pluto’s atmosphere is approximately 80 degrees cooler than Titan’s.

This is one of the reasons why Earth and Mars have such hazy atmospheres. The atmosphere is rich in methane, which freezes at 91 K and then condenses onto particles in the Aerosol-2 layer. This makes the particles of the Aerosol-2 layer grow larger, and methane “snow” rains down on the layers beneath. At certain levels, this “snow” causes the atmospheres to appear like perpetual winter.

To understand the hazy atmosphere on these planets, scientists must understand the composition of their atmospheres. Although Uranus’ atmosphere is vibrant blue, it is also a pale cyan color. The haze particles in Uranus’ atmosphere make the planets appear whiter. This can explain the different color of the two planets. This is the first model to explain the difference between them. It is also the first to explain the differences in haze particles between Neptune and Uranus.

The hazy atmosphere on the two blue planets may be the cause of their blue skies. In the meantime, scientists are working on finding a reason for the haze on Uranus’ atmosphere. Scientists believe that methane-based clouds are responsible for hazes on the two planets. This explanation is more likely to be correct than we think. This new theory may be useful in understanding the atmospheres of some blue planets.


The azure blue color of Jupiter, our closest neighbor to the sun, is not due to its tropical ocean. Its color is due to the turbulent atmosphere that is laced with silicate particles that scatter blue light. This pattern has already been observed from earlier observations, but Hubble’s new data provides robust confirmation. The researchers also believe that water vapor is the primary source of the planet’s blue hue.

In the solar system, the UV radiation from the Sun separates water molecules into oxygen and hydrogen. Two light hydrogen atoms escape into space while the highly reactive oxygen atom heads the other way. These free oxygen atoms rapidly oxidize any metallic minerals on the surface. On the other hand, the radiation from the Sun can damage living organisms. Thus, scientists believe that a blue planet might be more dangerous to life than Earth.

In addition to being able to observe Earth’s X-rays, scientists have also discovered radiation from stars that orbit other planets. While the Sun emits the strongest X-rays, other stars produce a higher EUV and UV flux. Its atmosphere also behaves similarly to Jupiter and Saturn, so scientists were surprised by the finding. The discovery of an additional source of radiation on Uranus could have major implications for our understanding of the blue planets.

Astronauts living on space stations are exposed to higher doses than other people. These astronauts orbit Earth at a distance of 400 km. Their exposure to radiation is so high that astronauts would receive the same amount of radiation as air crew in 12 days. In fact, national space agencies have already established career dose limits for astronauts. Various studies have indicated a connection between the astronauts’ exposure to radiation and certain types of cancer or tissue reactions. However, these findings are not conclusive, due to the small sample sizes.

Distance from host star

The azure hue of the Blue Planet HD 189733b is not a reflection from the ocean, but the result of a turbulent atmosphere laced with silicate particles that scatter blue light. Scientists believe this planet is a hot Jupiter, similar to Earth in its size and mass, and it lies close to its host star. The distance between the planet and the star is roughly nine light-years.

The distance between the planet and its host star is very close to the limit of the extended habitable zone. This limits the distance of the Blue Planets from their host stars to 0.17 light-years, or about one billion kilometers. Such a distance is too close for the Solar System to terraform B-type stars. Objects in the Kuiper Belt, however, should be very far from these stars.

To detect exoplanets, researchers use the radial-velocity method. During a transit, a planet’s star will move in a circle or ellipse, responding to the gravitational tug of a smaller companion. The resulting movement will alter the normal spectrum of the star. The light from the star will be shifted toward shorter wavelengths, while that from its other side will be red-shifted.

The distance to the habitable zone is huge, but scientists have predicted that some blue planets may be inhabited within a few billion years. The Internet Stellar Database has information on possible orbits of blue planets and the visual comfort zone. Rigel and Deneb would be far from Earth, but their orbital period is 669 years and 829 years, respectively. If Rigel and Deneb were to orbit the star, the center of the habitable zone would be much farther away than the current limit.