Brown Dwarf – Definition, Characteristics, Formation, and Examples   Recently updated !

A brown dwarf is a substellar object that forms much like a star but does not have enough mass to sustain hydrogen fusion in its core. Brown dwarfs occupy the fascinating boundary between the largest planets and the smallest stars. They are generally more massive than giant planets such as Jupiter but less massive than red dwarf stars.

Brown dwarfs are sometimes called failed stars, although this description is somewhat misleading. They form through gravitational collapse, as stars do, and some briefly fuse deuterium or lithium. However, their cores never become hot and dense enough to sustain the hydrogen fusion that powers main-sequence stars. Instead, brown dwarfs gradually radiate away the heat left from their formation and become cooler and fainter over time.

Brown dwarfs are especially interesting because they share properties with both stars and planets. Their formation and internal structure resemble those of stars, while their atmospheres may contain clouds, storms, water vapor, methane, and other features more reminiscent of giant planets. Studying them helps astronomers understand star formation, planetary atmospheres, and the poorly defined boundary between planets and stars.

Key Takeaways: Brown Dwarf

• A brown dwarf is a substellar object that lacks enough mass to sustain ordinary hydrogen fusion.
• Brown dwarfs generally lie between giant planets and the smallest true stars in mass.
• A commonly quoted brown dwarf mass range is about 13 to 80 Jupiter masses, although mass alone does not provide a perfect definition.
• Brown dwarfs form primarily through gravitational collapse, much like stars.
• More massive brown dwarfs briefly fuse deuterium, and some also burn lithium.
• Unlike main-sequence stars, brown dwarfs continually cool and become less luminous with age.
• Brown dwarfs are approximately the size of Jupiter despite being many times more massive.
• Their atmospheres can contain clouds, storms, water vapor, methane, carbon monoxide, and other molecules.
• Brown dwarfs are classified mainly into the M, L, T, and Y spectral classes, with L, T, and Y encompassing most objects usually recognized as brown dwarfs.
• Brown dwarfs emit most of their radiation at infrared wavelengths, making infrared telescopes especially useful for finding and studying them.
• Brown dwarfs can have disks and potentially planets.
• The closest known brown dwarfs are the two members of the Luhman 16 binary system, about 6.5 light-years from the Sun.

Why Are Brown Dwarfs Important?

Brown dwarfs help astronomers investigate several fundamental questions about stars and planets.

First, they test theories of star formation. Astronomers want to know how small an object can be and still form through the collapse and fragmentation of a molecular cloud. Observations with the James Webb Space Telescope have identified candidate brown dwarfs with masses of only a few times that of Jupiter, demonstrating that star-like formation processes can apparently produce surprisingly low-mass objects.

Brown dwarfs also provide natural laboratories for studying planet-like atmospheres. Because a brown dwarf does not usually orbit a much brighter star, astronomers can study its spectrum directly. Its atmosphere may have temperatures and chemical conditions similar to those of giant exoplanets without the glare of a host star interfering with observations.

Finally, brown dwarfs illuminate the boundary between stars and planets. The discovery of objects that overlap giant planets in mass, temperature, and atmospheric chemistry has shown that there is no simple physical dividing line between the two categories.

History of Brown Dwarfs

The existence of brown dwarfs was predicted decades before astronomers conclusively detected one.

In 1963, Indian-American astrophysicist Shiv S. Kumar calculated that objects below a certain mass would never become hot enough in their cores to sustain hydrogen fusion. These hypothetical objects were initially called black dwarfs, although that term was also used for theoretical cooled stellar remnants.

In 1975, astronomer Jill Tarter proposed the name brown dwarf. The term avoided confusion with black dwarfs and has remained in use even though brown dwarfs are not actually brown.

Finding them proved difficult. Brown dwarfs are intrinsically faint, and much of their radiation occurs in the infrared rather than visible wavelengths.

The breakthrough came in 1995 with the confirmation of Gliese 229B, a companion to the red dwarf star Gliese 229. Its spectrum showed methane, a striking indication that it was much cooler than an ordinary star. Gliese 229B became the first widely accepted, unambiguous brown dwarf.

Another important object announced around the same time was Teide 1, a brown dwarf in the Pleiades star cluster.

Infrared surveys subsequently transformed the field. The Two Micron All Sky Survey (2MASS), Sloan Digital Sky Survey (SDSS), and NASA’s Wide-field Infrared Survey Explorer (WISE) uncovered large populations of cool nearby objects.

Today, the James Webb Space Telescope can study the atmospheres and chemistry of brown dwarfs with unprecedented sensitivity and can detect extremely low-mass objects in young star-forming regions.

What Is a Brown Dwarf?

A brown dwarf is an object with insufficient mass to sustain the proton-proton chain, the principal hydrogen-fusion reaction that powers stars such as the Sun.

A newly forming star contracts under its own gravity. Gravitational potential energy becomes thermal energy, increasing the temperature and pressure of the core.

If the object has sufficient mass, its central temperature eventually becomes high enough for sustained hydrogen fusion. It becomes a main-sequence star.

A brown dwarf never reaches this point.

Instead, increasing pressure eventually produces significant electron degeneracy pressure, which helps resist further compression. The core stops heating sufficiently to initiate sustained hydrogen burning.

This difference separates brown dwarfs from true stars.

Brown Dwarf Mass

The often-cited mass range for brown dwarfs is approximately:

13 to 80 Jupiter masses (Mⱼ)

or roughly:

0.012 to 0.076 solar masses (M☉)

The boundaries are approximate rather than absolute. Composition, age, rotation, and the precise definition used all affect the limits.

The lower boundary near 13 Jupiter masses corresponds approximately to the minimum mass required for deuterium fusion.

The upper boundary near 75 to 80 Jupiter masses corresponds approximately to the minimum mass necessary for sustained ordinary hydrogen fusion.

However, astronomers increasingly recognize that formation history may be as important as mass when distinguishing giant planets from brown dwarfs. NASA, for example, notes both the traditional 13–80 Jupiter-mass range and the difficulty of classifying some free-floating planetary-mass objects.

Is a Brown Dwarf a Failed Star?

The phrase failed star is commonly used for brown dwarfs, and it captures an important part of their nature.

Brown dwarfs generally form through the same basic process as stars: gravitational collapse and fragmentation of clouds of gas and dust. They simply do not accumulate enough mass to sustain hydrogen fusion.

So, in that limited sense, a brown dwarf is a failed star.

But the term can also be misleading. Brown dwarfs are not defective objects or stars that somehow malfunctioned. They are a naturally occurring class of astronomical object with their own physical properties and evolutionary paths.

A better description is substellar object.

Is a Brown Dwarf a Failed Planet?

Usually, no.

A giant planet such as Jupiter forms primarily within a protoplanetary disk surrounding a young star, through processes such as core accretion or possibly disk instability.

Brown dwarfs generally form more like stars, through direct gravitational collapse.

This creates an important distinction:

Stars and brown dwarfs are primarily distinguished by whether they sustain hydrogen fusion, while brown dwarfs and planets may be distinguished partly by how they formed.

But nature does not always fit neatly into human categories. Some free-floating objects have masses below the traditional deuterium-burning boundary, while some massive companions to stars overlap the brown dwarf mass range. Formation history is often difficult to determine after the fact.

For this reason, the boundary between brown dwarf, giant planet, and free-floating planetary-mass object remains an active area of research.

Brown Dwarf vs Star vs Planet

The mass ranges overlap, so the table represents useful generalizations rather than rigid definitions.

Brown Dwarf Properties

Temperature depends strongly on both mass and age. A young, low-mass brown dwarf can be warmer than an old, more massive one.

What Does a Brown Dwarf Look Like?

Despite the name, a brown dwarf would not necessarily look brown.

A relatively hot brown dwarf might appear dull red or magenta to human eyes. Cooler examples would emit so little visible light that they would appear nearly black.

Most of their radiation lies in the infrared.

Their atmospheres may look surprisingly planet-like. Models and observations indicate cloud bands, patchy clouds, strong winds, and enormous storms. Some brown dwarfs vary in brightness as they rotate because atmospheric features move into and out of view. NASA illustrations consequently often depict them with Jupiter-like bands and storms.

Brown Dwarf Atmospheres and Weather

One of the most exciting areas of brown dwarf research concerns their weather.

Depending on temperature, brown dwarf atmospheres may contain clouds composed of substances that would be unusual on Earth.

Hotter L dwarfs can form clouds containing mineral particles and condensates such as silicates and iron.

As an object cools into the T class, many of these clouds sink below the visible atmosphere, while methane becomes increasingly prominent.

The coldest Y dwarfs have temperatures approaching those found on planets. Water vapor is abundant in their spectra, and at sufficiently low temperatures water clouds may form.

Brown dwarf atmospheres can also contain:

• molecular hydrogen (H₂)
• water vapor (H₂O)
• methane (CH₄)
• carbon monoxide (CO)
• ammonia (NH₃)
• alkali metals
• silicate and iron condensates

Because brown dwarfs have no solid surface in the ordinary sense, their observable “surface” is an atmospheric layer from which radiation escapes.

How Big Is a Brown Dwarf?

One of the most surprising facts about brown dwarfs is that mass does not translate into dramatically greater size.

A brown dwarf containing dozens of times Jupiter’s mass may still have a radius close to that of Jupiter.

As mass increases, stronger gravity compresses the object’s interior more strongly. Electron degeneracy also becomes important. Consequently, adding mass tends to increase density rather than radius.

Gliese 229B, for example, has tens of times Jupiter’s mass but approximately Jupiter’s diameter.

This means that a brown dwarf can be far denser and much more massive than Jupiter while remaining roughly the same size.

How Brown Dwarfs Form

Most brown dwarfs appear to form through processes similar to those that produce stars.

A cold region within a molecular cloud becomes gravitationally unstable and begins collapsing. As material falls inward, it forms a dense central object surrounded initially by gas and often a disk.

The object contracts and heats.

But if the developing object does not accumulate enough material, its core never reaches the conditions necessary for sustained hydrogen fusion.

Several mechanisms could produce such low masses. A cloud fragment might simply contain little material. Interactions with nearby young stars could eject a developing brown dwarf from its birth environment before it accretes more gas. Radiation or stellar winds from nearby massive stars could also disrupt accretion.

Observations of young brown dwarfs with circumstellar disks and jets provide strong evidence that at least many of them form through essentially scaled-down versions of star formation.

At the lowest masses, however, distinguishing star-like formation from planet-like formation becomes increasingly difficult.

Brown Dwarf Evolution

A star spends most of its life maintaining a balance between gravitational contraction and the energy released by nuclear fusion.

A brown dwarf cannot maintain this balance through sustained hydrogen fusion.

Instead, it evolves primarily by cooling and contracting.

Immediately after formation, a brown dwarf is relatively hot and luminous because gravitational collapse releases substantial energy.

If its mass exceeds roughly 13 Jupiter masses, its interior becomes hot enough to fuse deuterium:

²H + ¹H → ³He + energy

This process lasts only temporarily because deuterium is scarce.

More massive brown dwarfs can also destroy lithium through nuclear reactions. This behavior provides astronomers with an important diagnostic known as the lithium test.

Eventually nuclear reactions cease.

The brown dwarf then continues radiating stored thermal energy into space, becoming progressively:

cooler → dimmer → redder in its spectral energy distribution

Unlike ordinary stars, therefore, a brown dwarf does not have a single stable temperature determined primarily by its mass.

Age matters enormously.

Do Brown Dwarfs Live Forever?

In a sense, brown dwarfs have no conventional stellar lifespan.

A Sun-like star eventually exhausts its nuclear fuel and leaves the main sequence. A brown dwarf has no long-lived main-sequence stage to begin with.

Instead, it simply continues cooling.

Over extremely long timescales, a brown dwarf should become colder, fainter, and increasingly difficult to detect. The universe is only about 13.8 billion years old, so even the oldest brown dwarfs have not approached their ultimate state.

Thus, estimates of a brown dwarf “lifespan” can be misleading. There is no point at which it suddenly dies. In principle, it continues cooling for trillions of years and vastly longer.

Brown Dwarf Classification

Brown dwarfs extend the familiar stellar spectral classification system into much cooler temperatures.

The principal relevant spectral classes are:

M → L → T → Y

M Dwarfs

The coolest M-type objects include both very low-mass stars and young brown dwarfs.

Their spectra commonly show molecular absorption features such as titanium oxide and vanadium oxide.

L Dwarfs

L dwarfs are cooler than typical M dwarfs and have effective temperatures broadly around 1,300–2,400 K, although boundaries vary.

Their atmospheres can contain thick clouds of silicate and iron particles.

Some L dwarfs are low-mass stars, while many are brown dwarfs.

T Dwarfs

T dwarfs are cooler, with methane becoming a major spectral signature.

Their temperatures broadly span about 500–1,300 K.

These objects are sometimes called methane dwarfs.

Y Dwarfs

Y dwarfs are the coldest recognized spectral class of brown dwarfs.

Their temperatures can fall below about 500 K, approaching temperatures familiar from planets rather than stars.

NASA’s WISE mission has been especially important in discovering these exceptionally cool objects.

Examples of Brown Dwarfs

Several brown dwarfs have played important roles in astronomy.

Gliese 229B

Gliese 229B was the first unambiguous brown dwarf to be confirmed. It orbits the red dwarf Gliese 229, approximately 18 light-years away.

Its discovery in the 1990s provided convincing evidence that the long-predicted brown dwarf population actually existed.

Teide 1

Teide 1 lies in the Pleiades star cluster. Its youth and membership in a cluster of known age helped astronomers determine its substellar nature.

Luhman 16A and Luhman 16B

The binary system Luhman 16, formally WISE J104915.57−531906.1, contains two brown dwarfs approximately 6.5 light-years from Earth.

They are the closest known brown dwarfs to the Solar System and among our nearest astronomical neighbors.

WISE 0855−0714

WISE J085510.83−071442.5, usually shortened to WISE 0855−0714, is an exceptionally cold nearby brown dwarf about 7.2 light-years away.

Its temperature is comparable to temperatures found on Earth, making it an extraordinary laboratory for studying cold planetary-type atmospheres.

What Is the Closest Brown Dwarf to Earth?

The closest known brown dwarfs are Luhman 16A and Luhman 16B, approximately 6.5 light-years away in the southern constellation Vela.

Because they form a binary system, neither can simply be designated the uniquely closest without considering their orbital positions.

Luhman 16 is the third-closest known stellar or substellar system to the Sun, after the Alpha Centauri system and Barnard’s Star.

The fact that such a nearby system remained undiscovered until 2013 illustrates just how difficult brown dwarfs are to detect.

How Common Are Brown Dwarfs?

Brown dwarfs appear to be common throughout the Milky Way, although determining their exact abundance remains challenging.

They are intrinsically faint, and old, cool brown dwarfs can be extremely difficult to detect even when they are relatively nearby. Surveys therefore become increasingly incomplete for the coldest and lowest-luminosity objects.

Brown dwarfs occur:

• alone in interstellar space
• in binary brown dwarf systems
• as companions to stars
• in young star clusters
• in star-forming regions

Observations suggest that the mechanisms producing brown dwarfs are widespread, but brown dwarfs do not appear to outnumber ordinary stars as dramatically as some early theories proposed.

The Brown Dwarf Desert

An interesting observational phenomenon is the brown dwarf desert.

Astronomers have found many low-mass stellar companions and many giant planets orbiting Sun-like stars. Yet relatively few brown dwarfs orbit such stars at close distances.

This shortage is called the brown dwarf desert.

Its existence probably contains clues about formation. The mechanisms that efficiently produce binary stars and planetary systems may be relatively inefficient at placing brown dwarf-mass companions into close orbits around Sun-like stars.

Brown dwarfs are found at wider separations, however, so the “desert” does not mean that stars never have brown dwarf companions.

How Do Scientists Detect Brown Dwarfs?

Brown dwarfs are difficult to discover because they emit little visible light.

Infrared Surveys

The most effective searches use infrared wavelengths, where cool brown dwarfs emit much of their radiation.

Major surveys and observatories involved in brown dwarf research include 2MASS, WISE, Spitzer, Hubble, and the James Webb Space Telescope.

Spectroscopy

Astronomers split the radiation from an object into a spectrum.

Absorption features from molecules such as:

H₂O, CH₄, CO, and NH₃

reveal atmospheric composition and help determine spectral type and temperature.

Parallax

Astronomers measure the apparent motion of a nearby brown dwarf against more distant background stars as Earth moves around the Sun.

This stellar parallax gives its distance.

Proper Motion

Nearby brown dwarfs often display noticeable movement across the sky over several years. Searching for infrared objects with high proper motion has revealed several nearby systems.

The Lithium Test

Lithium provides a particularly useful method of distinguishing some brown dwarfs from stars.

Low-mass brown dwarfs never become hot enough to destroy their primordial lithium. Detecting lithium in an object’s spectrum can therefore indicate that its mass lies below the threshold for lithium burning.

However, the test depends on both mass and age, so it is not universally applicable.

Measuring Orbits

When brown dwarfs occur in binary systems, astronomers track their orbital motion. Kepler’s laws then provide especially valuable estimates of their masses.

Brown Dwarf Rotation and Magnetic Fields

Brown dwarfs often rotate surprisingly quickly.

Some complete a rotation in only a few hours. Observations have found extremely rapid objects approaching what may be a physical rotational speed limit.

Despite lacking the same internal structure as ordinary stars, brown dwarfs can also possess strong magnetic fields.

Some emit radio waves and display aurora-like phenomena. Magnetic activity provides another intriguing connection between brown dwarfs, low-mass stars, and magnetized planets such as Jupiter.

Can a Brown Dwarf Have Planets?

Yes. There is no physical reason a brown dwarf cannot have planets.

Young brown dwarfs have been observed with circumstellar disks, including disks containing the raw materials necessary for planet formation.

Planets could potentially form within these disks through processes similar to those operating around young stars.

The terminology can become awkward. If a Jupiter-sized object orbits something only several times more massive than Jupiter, distinguishing between a planet-moon system, binary planetary-mass system, and brown dwarf-planet system may depend partly on how the objects formed.

Nevertheless, planetary systems around brown dwarfs are physically plausible and are an important target of observational research.

Could Planets Around Brown Dwarfs Support Life?

In principle, a planet orbiting a brown dwarf could receive enough energy for liquid water to exist on its surface.

However, brown dwarf habitability presents unusual problems.

Because a brown dwarf cools continuously, its habitable zone moves inward over time.

A planet at a fixed distance might therefore experience a sequence such as:

too hot → potentially habitable → too cold

rather than remaining in a relatively stable habitable zone for billions of years as Earth has.

The habitable zone would also lie extremely close to the brown dwarf. Planets there would likely become tidally locked, keeping one hemisphere permanently facing the brown dwarf.

Strong tidal heating could further affect climate and geology.

Early heating may also cause a planet to lose substantial water before it reaches more favorable temperatures. For these reasons, theoretical studies generally regard long-term brown dwarf habitability as possible but challenging.

Modern models continue to refine this picture. For example, cloud formation and temporary deuterium burning can slow brown dwarf cooling and may allow planets to remain within favorable temperature ranges longer than simpler models predict.

Brown Dwarfs vs Red Dwarfs

Brown dwarfs are sometimes confused with red dwarfs, but the difference is fundamental.

A red dwarf is a true star.

Even the smallest red dwarf has sufficient mass to maintain hydrogen fusion in its core. A brown dwarf does not.

The distinction becomes difficult near the hydrogen-burning boundary because the coolest stars and warmest brown dwarfs can have similar temperatures and spectra.

Brown Dwarf vs Gas Giant

Brown dwarfs and gas giants can be remarkably similar in size and atmospheric appearance.

However, their origins and internal conditions usually differ.

Jupiter formed within the Sun’s protoplanetary disk. A typical brown dwarf forms independently through gravitational collapse.

A massive brown dwarf also experiences much greater internal pressure and may temporarily undergo deuterium or lithium fusion.

The difference between them is therefore more complicated than simply saying that brown dwarfs are big planets.

Common Misconceptions About Brown Dwarfs

Misconception: Brown dwarfs are brown.

Brown dwarfs do not literally appear brown. Hotter examples would appear reddish, while the coolest ones emit almost no visible light.

Misconception: Brown dwarfs are small stars.

Brown dwarfs are classified as substellar objects, not true stars, because they cannot sustain hydrogen fusion.

Misconception: Brown dwarfs never undergo nuclear fusion.

Many brown dwarfs temporarily fuse deuterium, and sufficiently massive ones can destroy lithium. What they cannot do is maintain ordinary hydrogen fusion.

Misconception: A brown dwarf is simply a very large Jupiter.

Brown dwarfs and giant planets share many physical characteristics, but they generally form through different processes.

Misconception: Brown dwarfs eventually become stars.

An isolated brown dwarf does not become hotter as it ages. It becomes cooler. Unless it gains considerable additional mass, it never becomes a hydrogen-burning star.

Misconception: Brown dwarfs eventually become black dwarfs.

A black dwarf is the hypothetical final state of a white dwarf after it cools for an enormously long time. It is unrelated to a brown dwarf.

Misconception: Brown dwarfs are dark matter.

Brown dwarfs contribute ordinary baryonic matter to galaxies, but observations show they cannot account for the universe’s missing dark matter.

Interesting Brown Dwarf Facts

• Brown dwarfs were predicted more than 30 years before their existence was conclusively confirmed.
• The name “brown dwarf” was coined by astronomer Jill Tarter.
• A brown dwarf dozens of times more massive than Jupiter can still be roughly Jupiter’s size.
• Brown dwarfs can have clouds and enormous storms.
• Some brown dwarfs rotate in only a few hours.
• Brown dwarfs can produce radio emission and auroral activity.
• The coldest brown dwarfs have temperatures more characteristic of planets than stars.
• The closest known brown dwarf system is only about 6.5 light-years away.
• Brown dwarf atmospheres provide useful analogs for studying giant exoplanets.
• Extremely low-mass brown dwarfs blur the traditional boundary between stars and planets.

Frequently Asked Questions

What is a brown dwarf?

A brown dwarf is a substellar object that forms much like a star but lacks enough mass to sustain hydrogen fusion in its core.

Is a brown dwarf a star?

No. Brown dwarfs are substellar objects because they cannot sustain the hydrogen fusion that defines main-sequence stars.

Is Jupiter a brown dwarf?

No. Jupiter is a planet. It formed within the Sun’s protoplanetary disk and has only about one Jupiter mass. A traditional brown dwarf is generally much more massive.

How massive is a brown dwarf?

Brown dwarfs are commonly described as having masses of approximately 13 to 80 times the mass of Jupiter, although these boundaries are approximate.

How big is a brown dwarf?

Most brown dwarfs have radii roughly comparable to Jupiter’s, despite containing many times more mass.

How hot is a brown dwarf?

Brown dwarf temperatures span a very wide range depending on mass and age. Known objects range from thousands of kelvins for young or relatively massive brown dwarfs to only a few hundred kelvins for the coldest Y dwarfs.

What is the closest brown dwarf to Earth?

The closest known brown dwarfs are Luhman 16A and Luhman 16B, approximately 6.5 light-years from the Solar System.

Can brown dwarfs have planets?

Yes. Brown dwarfs can possess disks in which planets may form, and planetary-mass companions have been found around substellar objects.

Can a brown dwarf support life?

Life directly on a brown dwarf as we understand it is extremely unlikely because it is a giant gaseous object without a conventional solid surface. However, a planet orbiting a brown dwarf could theoretically experience temperatures compatible with liquid water for part of the brown dwarf’s evolution.

Do brown dwarfs produce light?

Yes. Brown dwarfs emit their own electromagnetic radiation because they are warm. Most of their radiation emerges at infrared wavelengths rather than as visible light.

Do brown dwarfs have nuclear fusion?

Some do temporarily. Brown dwarfs above roughly 13 Jupiter masses can burn deuterium, while more massive brown dwarfs can also burn lithium. They cannot sustain the ordinary hydrogen fusion that powers true stars.

What happens to a brown dwarf when it dies?

A brown dwarf does not “die” in the way a star does. It continually radiates away its internal heat, becoming colder and dimmer over extraordinarily long periods of time.

Could a brown dwarf become a star?

A brown dwarf could theoretically become a star if it acquired enough additional mass to cross the hydrogen-burning limit. An isolated brown dwarf, however, simply cools as it ages.

References

• Burrows, Adam; Hubbard, William B.; Lunine, Jonathan I.; Liebert, James (2001). “The Theory of Brown Dwarfs and Extrasolar Giant Planets”. Reviews of Modern Physics. 73 (3): 719–765. doi:10.1103/RevModPhys.73.719
• Luhman, Kevin (2009). “Discovery of a Wide Binary Brown Dwarf Born in Isolation”. The Astrophysical Journal. 691 (2): 1265. doi:10.1088/0004-637X/691/2/1265
• Luhman, Kevin L.; Adame, Lucía; et al. (2005). “Discovery of a Planetary-Mass Brown Dwarf with a Circumstellar Disk”. The Astrophysical Journal. 635 (1): L93–L96. doi:10.1086/498868
• Sorahana, Satoko; Yamamura, Issei; Murakami, Hiroshi (2013). “On the Radii of Brown Dwarfs Measured with AKARI Near-infrared Spectroscopy”. The Astrophysical Journal. 767 (1): 77. doi:10.1088/0004-637X/767/1/77
• Springer, Cham (2014). Joergens, Viki (ed.). 50 Years of Brown Dwarfs. Astrophysics and Space Science Library. Vol. 401. SpringerLink. XI, 168. doi:10.1007/978-3-319-01162-2. ISBN 978-3-319-01162-2.