There is a very cold thing in space.
It is not a bright star. It stays dark and dim. It feels like the air in your room. It is very far away from us. Can you find it in the sky?
{
"text": "There is a very cold object in space.
\n\nIt is not a bright star. It is a brown dwarf. This object is very cold. Its heat feels like the air in your room.\n\nIt is the fourth closest thing like this to our Sun. A man named Kevin Luhman found it in 2013. He used a special telescope to see it.\n\nThis object is very dim. It is hard to see with our eyes. We must use special tools to find it.\n\nIt might even have clouds. These clouds could be made of water ice. It is a very strange place in the
There is a very cold object in space. It is called WISE 0855−0714. Scientists call it a brown dwarf.
A brown dwarf is a type of object that is not quite a star. It is much bigger than a planet. But it is not big enough to make its own light like a star does. This object is the coldest brown dwarf found so far. Its temperature is about 250 Kelvin. That is close to the temperature of a room.
Kevin Luhman found it in 2013. He used data from the WISE telescope. This object is very dim. It is almost invisible in normal light. We must use infrared telescopes to see it. These telescopes see heat instead of light.
The object might have clouds in its air. Some studies suggest it has water ice clouds. There may also be clouds made of sulfide. Scientists use the James Webb Space Telescope to study it. They want to see how water moves in its air. This object is the fourth closest system to our Sun. It moves through space very quickly.
There is a very strange object drifting through space. Scientists call it WISE 0855−0714, or W0855 for short. It is a brown dwarf located in the Hydra constellation.
A brown dwarf is a type of object that is not quite a star. It is much bigger than a planet. However, it is not heavy enough to make its own light like a star does. W0855 is the coldest brown dwarf ever found. Its temperature is about 250 Kelvin. This is very close to the temperature of a normal room. Because it is so cold, it is almost invisible in normal light.
This object works in a very interesting way. It does not shine with its own light. Instead, its light comes from thermal radiation. This is just another way to say heat. Because it is so dim, we must use special infrared telescopes to see it. These telescopes can pick up the heat coming from the object. Scientists use the WISE telescope and the James Webb Space Telescope to study it.
They can see things like methane and water vapor in its air. They also look at how water moves through the atmosphere. Some scientists think water might condense and fall like rain. This is called rainout, where water turns into particles and sinks.
Kevin Luhman discovered this object in March 2013. He was looking at data from the Wide-field Infrared Survey Explorer, or WISE. He noticed that the object had a very high proper motion. This means it moves across our view of the sky very quickly. To be sure about what he found, he used other tools. He used the Spitzer Space Telescope and the Gemini North telescope.
NASA announced the discovery in an official press release in April 2014. It is now known as the fourth-closest stellar or substellar system to our Sun.
There are many important numbers that describe W0855. It is about 7 light-years away from our Sun. Its mass is estimated to be between 3 and 10 Jupiter masses. This makes it a planetary-mass object. It is also the third-fastest moving object after Kapteyn's Star and Barnard's Star.
In November 2024, a team found deuterated methane in its atmosphere. They also found a tiny amount of phosphine. This helped prove that its mass is below the limit for deuterium fusion. This is a special process that happens inside larger stars.
Thinking about W0855 can help us understand our own solar system. It is a free-floating object, which means it does not orbit a star. It is like a rogue planet wandering through the dark.
Even though it is far away, it is very close to us in space. We can compare its clouds to the clouds on Jupiter. Scientists even looked for moons around it using the James Webb Space Telescope. They did not find any moons as large as Titan.
Studying W0855 helps us learn how different objects in the universe work.
WISE 0855−0714, often called W0855, is a unique celestial object located in the Hydra constellation. It is classified as a Y4 spectral class brown dwarf. A brown dwarf is a substellar object that occupies the space between the largest planets and the smallest stars. W0855 is particularly significant because it is the coldest brown dwarf ever discovered. Its temperature is approximately 250 Kelvin. This temperature is remarkably close to typical room temperature on Earth. Because it is so cold, it emits very little visible light.
The object does not produce light through the same nuclear processes as stars. Instead, its luminosity comes from thermal radiation, which is the energy released as heat. Because this radiation is mostly in the infrared spectrum, W0855 is nearly invisible to the human eye. Scientists must use specialized infrared telescopes to observe it. The Wide-field Infrared Survey Explorer, or WISE, first imaged the object on May 4, 2010. The James Webb Space Telescope (JWST) is also used to study its faint signals. These tools allow astronomers to detect wavelengths that visible light telescopes cannot see.
Understanding the atmosphere of W0855 requires complex spectrometry, which is the study of how light interacts with matter. Observations using the Gemini North Telescope and the JWST have revealed a complex chemical makeup. Scientists have detected methane (CH4), water vapor (H2O), ammonia (NH3), and carbon monoxide (CO). There is evidence of a hydrological cycle, which is the movement of water through an atmosphere. In the upper atmosphere, water vapor can condense into particles. This leads to a process called rainout, where water sinks into the lower atmosphere. This process may explain why some models predict more water ice clouds than are actually observed.
The history of this discovery began when astronomer Kevin Luhman analyzed WISE data in March 2013. He was searching for potential binary companions to our Sun. During this search, he noticed W0855 had an unusually high proper motion. Proper motion is the measurable movement of a star across the sky relative to distant objects. To confirm his findings, Luhman used the Spitzer Space Telescope and the Gemini North telescope between 2013 and 2014. NASA officially announced the discovery in an April 2014 press release. This discovery provided a new way to study objects that exist at the boundary of planets and stars.
Several specific measurements define the physical nature of W0855. It is located approximately 7 light-years away from the Sun. This distance makes it the fourth-closest stellar or substellar system to our solar system. Its mass is estimated to be between 3 and 10 Jupiter masses. This mass is below the 13 Jupiter mass limit required for deuterium fusion. Deuterium fusion is a nuclear reaction that occurs in larger brown dwarfs. Because it cannot perform this fusion, some scientists call it a free-floating planetary-mass object. It also has the third-highest proper motion, following only Barnard's Star and Kapteyn's Star.
Recent studies have uncovered surprising details about the chemical composition of W0855. In November 2024, researchers detected deuterated methane (CH3D) using archived and new JWST data. They also found a very small amount of phosphine (PH3), roughly one part per billion. This tiny amount of phosphine was unexpected based on previous chemical predictions. Furthermore, the atmosphere contains a specific ratio of nitrogen isotopes. It contains about 99.7% 14N and about 0.3% 15N. This enrichment of 15N suggests the object may have formed from a younger interstellar medium cloud.
Finally, W0855 provides a way to test our theories about planetary systems and formation. Astronomers used 11 hours of JWST observations to search for exomoons, which are moons orbiting planets outside our solar system. They looked for transits, where a moon passes in front of the object and causes a dip in light. No transits were found, meaning there are no moons at least twice the size of Saturn's moon Titan. Studying W0855 helps scientists understand how isolated, cold objects behave in the galaxy. It connects the study of massive planets to the study of the smallest, coolest stars.
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