The planets that orbit too close to their stars to sustain life, The gas giants called “hot Jupiter” – planets that circle too close to their stars to save life – are some of the weirdest worlds found outside our solar system.
Recent observations have shown that the hottest of them are still unfamiliar and susceptible to widespread interference so serious that they tear up the molecules that make up the atmosphere.
The planet designated as KELT-9b is a very hot Jupiter, one of several extrasolar planets – planets around other stars – that have been found in our galaxy. The planets that orbit too close to their stars to sustain life.
Weighing nearly three times the mass of our own Jupiter and orbiting a star about 670 light-years away. With a surface temperature of 4,300 degrees Celsius – hotter than some stars – the planet is the hottest.
Now a team of astronomers using NASA’s Spitzer Space Telescope has found evidence that heat is too large for molecules to remain intact. Hydrogen gas molecules tend to break at the end of KELT-9b and can only form again when the separate atoms disappear on the planet at night.
Although still very hot, gentle night cooling is enough to reshape hydrogen gas molecules – that is, until they flow back to the day they broke again.
There are several other hot Jupiters and ultra-hot Jupiters that are not too hot, but are still warm enough for this effect to occur.
Science has only just begun to study the exoplanet atmosphere and study the hottest and brightest molecular melt. KELT-9b remains relatively firm among the uninhabited world. Astronomers became aware of a very hostile environment in 2017 when they were first discovered using the Kilodegree Extremely Little Telescope (KELT) system. Observations were made from two robot telescopes, one in southern Arizona and one in South Africa.
In a study by the Astrophysical Journal Letters, the scientific team used the Spitzer space telescope to analyze the temperature profile of these giant giants.
Spitzer, who makes observations in infrared light, can measure subtle changes in heat. These observations repeated for hours and allowed Spitzer to feel changes in the atmosphere as the planet gradually appeared as it orbited the star.
Different parts of the planet revolve around its star. This allows the team to know the difference between KELT-9b days and “nights”. In this case, the planet orbits its star so close that one year – once around the star – only lasts 1 1/2 days.
This means that the planet is well connected and represents the face of the star forever (because our moon is only the face on Earth). On the other hand KELT-9b, that night lasts forever.
But gas and heat flow from one side to the other. The big question for researchers trying to understand the exoplanet’s atmosphere is how radiation and flux balance.
The computer model is an important tool in the study, which shows how this atmosphere tends to behave at different temperatures.
Most relevant to the KELT-9b data is a model that breaks and rearranges hydrogen molecules, a process known as dissociation and recombination.
If you ignore hydrogen dissociation, you get very fast winds of 60 kilometers per second.
KELT-9b does not have a large temperature difference between day and night, which indicates that heat flows from one to another.
And the “hot spot” that day, which was said to be directly under the planet’s star, had been shifted from its expected position. Scientists don’t know why – another mystery that needs to be solved on this strange, hot planet.