Exoplanet WASP-104b is one of the least-reflective planets ever discovered. First identified in 2014 according to the Open Exoplanet Catalogue, WASP-104b belongs to a class of “exotic worlds” known as “hot Jupiters.”

These are gaseous exoplanets the size of Jupiter, only considerably much hotter because of their close proximity to their parent stars, which they orbit in less than 10 days, NASA explains.

Initially “considered oddballs,” hot Jupiters turned out to be quite common. Yet, although we’re used to them by know, they remain “shrouded in mystery,” NASA points out.

One thing we do know about hot Jupiters is that most of them are tidally locked — one side of the planet always faces its parent star, making it the permanent day side — and that they’re relatively dark, absorbing about 60 percent of the starlight that reaches them, notes Science Alert.

Last year, hot Jupiter WASP-12b made headlines when astronomers found out that it absorbs at least 94 percent of the light. At the time, this exoplanet was called “spooky” and “weird” and was described as “pitch black.”

But WASP-104b really takes the cake on this one. A new research by Keele University in the U.K. revealed that WASP-104b absorbs more than 97 to 99 percent of light.

Pause for gasp.

The research, a six-page paper published in the Cornell University Library, describes the exoplanet as being “darker than coal” (seriously, that’s what they put in the title) and deems it “one of the least-reflective planets found to date.”

Hot Jupiter WASP-104b is Darker Than Charcoal: WASP-104b, a so-called Hot Jupiter, has been identified in a new research as one of the least-reflective planets found to date. Astronomers classify a planet as a "Hot Jupiter" that are gas giant... https://t.co/k0ceVoVl1y — Rumor About (@rumorabout) April 23, 2018

“From all the dark planets I could find in the literature, this is top five-ish. I think top three,” lead researcher and astrophysicist Teo Mocnik said in a statement.

The authors analyzed data from NASA’s Kepler Space Telescope K2 mission, specifically the short-cadence data from Campaign 14, and found out that WASP-104b is surrounded by a thick, hazy atmosphere made up of atomic sodium and potassium. These elements absorb light in the visible spectrum, making the planet very dark on the day side (the only side that sees any starlight).

Since the planet is extremely close to its host star, WASP-104b is too hot for clouds to form in its atmosphere (on the day side, that it), which means there’s almost nothing there to reflect the light.

In fact, the exoplanet orbits its parent star — a yellow dwarf located about 466 light-years away from Earth, in the Leo constellation, Science Alert reports — from a distance of only 2.6 million miles. Remarkably, this peculiar planet completes a full orbit in just 1.75 days.

The only hot Jupiter that’s darker than WASP-104b is an exoplanet dubbed TrES-2b, which only reflects 0.1 percent of the light from its parent star, notes Science Alert.

A study has been revealed that WASP-104b, a Hot Jupiter exoplanet, has been discovered as one of the darkest exoplanets ever seen. https://t.co/APuAP36iRm — the Context (@thecontextnet) April 21, 2018

The media outlet clarifies, however, that these planets are not actually dark in color. In fact, judging by their extreme heat, they more likely glow in “a deep, bruise-like purple or a dull molten red” hue, Science Alert points out.

But WASP-104b is not the only hot Jupiter with an impressive tale to tell. In December, the world was acquainted with “death planet” WASP-18b, the first hot Jupiter with no water and an upper atmosphere almost completely made up of carbon monoxide.

Equally baffling is the hot Jupiter known as Kepler-13ab, a planet where the atmosphere “snows” titanium dioxide, the active ingredient used in most brands of sunscreen.</s>WASP-104b, a so-called Hot Jupiter, has been identified in a new research as one of the least-reflective planets found to date. Astronomers classify a planet as a "Hot Jupiter" that are gas giant exoplanets, physically similar to Jupiter but that has a very short orbital period with less than 10 days. The close proximity to their stars and high surface-atmosphere temperatures resulted in the moniker "hot Jupiters."

Researchers a the Keele University in the UK found the unique characteristic of WASP-104b by analyzing Kepler's K2 short-cadence data from Campaign 14. The exoplanet's close proximity to its star, a yellow dwarf, is likely the reason for the darkness.

Most hot Jupiters including the WASP-104b are tidally locked. One side of the planet always faces its star, making it the permanent day side. In the case of WASP-104b, the distance is only 2.6 million miles from the star and it only needs 1.75 days for a full orbit, according to ScienceAlert. Lead researcher Teo Mocnik talked to New Scientist about discovery (paywall).

The WASP-104b exoplanet was discovered back in 2014, along with the WASP-106b.

The detailed research can be found in the paper titled "WASP-104b is Darker than Charcoal" authored by T. Močnik, C. Hellier, J. Southworth and published in the Cornell University Library under arXiv:1804.05334.</s>Share this article with Google Plus

Scientists may have found a planet so dark and evil-looking it might be among the most heavy metal places in the known universe.

The planet is believed to be one of the darkest ever found: so completely black that it absorbs up to 99% of the light that hits it.

As they say in Spinal Tap: ‘None more black’.

Researchers have compared it to charcoal, and it’s a pretty horrendous place, no matter how ‘metal’ you are.

The planet is named Wasp-104b, and is a ‘hot Jupiter’, a gas giant as big as Jupiter in our solar system, but much, much closer to the star, ScienceAlert reports.

Most hot Jupiters are dark (and extremely, extremely hot) – but this one is far, far darker than expected.

Researchers at Keele University say that Wasp-104B is much darker, absorbing 97 to 99% of light.

Lead author Teo Mocnik said, ‘From all the dark planets I could find in the literature, this is top five-ish. I think top three.’

The reason it’s so dark is probably down to how close it is to its planet, a yellow dwarf in the constellation Leo.

It takes just 1.75 days to do a full orbit, being just 2.6 million miles from the star – and its thick hazy atmosphere may contain atomic sodium and potassium, which absorb light.</s>A new pitch-black planet that absorbs 99% of all light could be among the darkest celestial bodies ever uncovered, scientists say.

Particles found in the dense atmosphere of Wasp-104b, a planet dubbed a 'hot Jupiter' for its similarities to the gas giant, absorb almost all light.

The planet it so close to its host star that the reflective clouds that most planets have are burnt off.

As a result, it is left with a hazy layer thick with potassium and sodium atoms that absorb all light in the visible spectrum.

This means it appears as a dark lump - probably purple or molten red - very faintly glowing like an ember in a firepit.

Experts found the strange object thanks to the shadow it casts against its host, a yellow dwarf around 466 light-years away in the constellation Leo.

Researchers were able to track this 'transit' across the star's surface, which takes place once every 1.75 days.

The findings were made by researchers at Keele University, who used data from Nasa's Kepler space telescope to make the discovery.

'Hot Jupiters' are giant gas exoplanets that are physically similar to Jupiter but have a short orbital period of less than ten days.

Wasp-104b falls within a sub category of 'hot Jupiter' planets that appear to reflect virtually no light - more than 97 to 99 per cent in the case of this planet.

It is not known which is the darkest of all the planets as the difference comes down to a fraction of a per cent or even the margin of error in scientist's calculations, researchers say.

'From all the dark planets I could find in the literature, this is top five-ish,' lead researcher and astrophysicist Teo Mocnik told New Scientist. 'I think top three.'

Wasp-104b was first discovered in 2014 as part of the Wide Angle Search for Planets project that gives it its name.

Researchers at the time noted its fast orbit around its host star which is believed to lead to its unique ability to absorb light.

As with other 'hot Jupiters', the time it takes Wasp-104b to rotate on its axis matches the time it takes to orbit its host star - a characteristic called tidal locking that also affects our Moon.

This means that one side always faces its host star, and is constantly in daytime, and the other faces away in a permanent night.

As Wasp-104b circles so close to its star - around 2.6 million miles (4.3 million km), a fraction of Mercury's 36 million mile (58 million km) orbit around the sun - any reflective clouds that could form are swept away by its radiation.

This gives free reign for potassium and sodium particles to encircle the planet, giving its a thick, hazy atmosphere which absorbs light on its day side.

Planets in our own solar system have a wide range of properties, but they are distinguished by two: their size and their orbit. Their size determines if the planet can have a life-sustaining atmosphere, while the orbit affects the surface temperature and whether there could be liquid water on its surface. A habitable planet, one that could have liquid water on its surface, must be between about 80 to 200 per cent the diameter of Earth. Planets that are smaller than 8/10ths of an Earth diameter have less than half its mass. As a result, they do not have enough gravity to hold onto a life-sustaining atmosphere. Planets that are more than twice the diameter of Earth have about ten Earth masses and enough gravity to hold onto hydrogen, the most abundant element in the Universe. Such large planets turn into gas giants like Jupiter and Saturn. Jupiter is more than ten times the diameter of Earth and more than 300 times the mass of Earth. Most of the 300 plus planets that have been detected so far are gas giants. The first extra-solar planet detected around a star similar to the sun was 51 Peg. It has about the mass of Jupiter. Unlike Jupiter, which is five times as far from the sun as Earth and orbits the sun in 12 years, 51 Peg is twenty times closer to its star than Earth is to the sun and orbits its star every four days. Planets like these are referred to as 'Hot Jupiters'.

Clouds may form on the night side, but this receives no light from the host star which they could reflect.

In terms of its appearance, scientists say Wasp-104b's description as appearing darker than charcoal may be misleading.

Adam Burrows of Princeton University, who co-authored a paper in 2000 predicting these ultra-dark planets, told New Scientist: 'It’s probably going to be purple.'

The full findings of the study were published on the pre-print repository arXiv, and are awaiting peer review.
A study reveals that WASP-104b, a hot Jupiter exoplanet, is darker than charcoal and absorbs 99% of light.