Members Can Post Anonymously On This Site
-
Similar Topics
-
By NASA
Explore This Section Webb News Latest News Latest Images Blog (offsite) Awards X (offsite – login reqd) Instagram (offsite – login reqd) Facebook (offsite- login reqd) Youtube (offsite) Overview About Who is James Webb? Fact Sheet Impacts+Benefits FAQ Science Overview and Goals Early Universe Galaxies Over Time Star Lifecycle Other Worlds Observatory Overview Launch Orbit Mirrors Sunshield Instrument: NIRCam Instrument: MIRI Instrument: NIRSpec Instrument: FGS/NIRISS Optical Telescope Element Backplane Spacecraft Bus Instrument Module Multimedia About Webb Images Images Videos What is Webb Observing? 3d Webb in 3d Solar System Podcasts Webb Image Sonifications Team International Team People Of Webb More For the Media For Scientists For Educators For Fun/Learning 6 Min Read NASA’s Webb Peers Deeper into Mysterious Flame Nebula
This collage of images from the Flame Nebula shows a near-infrared light view from NASA’s Hubble Space Telescope on the left, while the two insets at the right show the near-infrared view taken by NASA’s James Webb Space Telescope. Credits:
NASA, ESA, CSA, M. Meyer (University of Michigan), A. Pagan (STScI) The Flame Nebula, located about 1,400 light-years away from Earth, is a hotbed of star formation less than 1 million years old. Within the Flame Nebula, there are objects so small that their cores will never be able to fuse hydrogen like full-fledged stars—brown dwarfs.
Brown dwarfs, often called “failed stars,” over time become very dim and much cooler than stars. These factors make observing brown dwarfs with most telescopes difficult, if not impossible, even at cosmically short distances from the Sun. When they are very young, however, they are still relatively warmer and brighter and therefore easier to observe despite the obscuring, dense dust and gas that comprises the Flame Nebula in this case.
NASA’s James Webb Space Telescope can pierce this dense, dusty region and see the faint infrared glow from young brown dwarfs. A team of astronomers used this capability to explore the lowest mass limit of brown dwarfs within the Flame Nebula. The result, they found, were free-floating objects roughly two to three times the mass of Jupiter, although they were sensitive down to 0.5 times the mass of Jupiter.
“The goal of this project was to explore the fundamental low-mass limit of the star and brown dwarf formation process. With Webb, we’re able to probe the faintest and lowest mass objects,” said lead study author Matthew De Furio of the University of Texas at Austin.
Image A: Flame Nebula: Hubble and Webb Observations
This collage of images from the Flame Nebula shows a near-infrared light view from NASA’s Hubble Space Telescope on the left, while the two insets at the right show the near-infrared view taken by NASA’s James Webb Space Telescope. Much of the dark, dense gas and dust, as well as the surrounding white clouds within the Hubble image, have been cleared in the Webb images, giving us a view into a more translucent cloud pierced by the infrared-producing objects within that are young stars and brown dwarfs. Astronomers used Webb to take a census of the lowest-mass objects within this star-forming region.
The Hubble image on the left represents light at wavelengths of 1.05 microns (filter F105W) as blue, 1.3 microns (F130N) as green, and 1.39 microns (F129M) as red. The two Webb images on the right represent light at wavelengths of 1.15 microns and 1.4 microns (filters F115W and F140M) as blue, 1.82 microns (F182M) as green, 3.6 microns (F360M) as orange, and 4.3 microns (F430M) as red. NASA, ESA, CSA, M. Meyer (University of Michigan), A. Pagan (STScI) Smaller Fragments
The low-mass limit the team sought is set by a process called fragmentation. In this process large molecular clouds, from which both stars and brown dwarfs are born, break apart into smaller and smaller units, or fragments.
Fragmentation is highly dependent on several factors with the balance between temperature, thermal pressure, and gravity being among the most important. More specifically, as fragments contract under the force of gravity, their cores heat up. If a core is massive enough, it will begin to fuse hydrogen. The outward pressure created by that fusion counteracts gravity, stopping collapse and stabilizing the object (then known as a star). However, fragments whose cores are not compact and hot enough to burn hydrogen continue to contract as long as they radiate away their internal heat.
“The cooling of these clouds is important because if you have enough internal energy, it will fight that gravity,” says Michael Meyer of the University of Michigan. “If the clouds cool efficiently, they collapse and break apart.”
Fragmentation stops when a fragment becomes opaque enough to reabsorb its own radiation, thereby stopping the cooling and preventing further collapse. Theories placed the lower limit of these fragments anywhere between one and ten Jupiter masses. This study significantly shrinks that range as Webb’s census counted up fragments of different masses within the nebula.
“As found in many previous studies, as you go to lower masses, you actually get more objects up to about ten times the mass of Jupiter. In our study with the James Webb Space Telescope, we are sensitive down to 0.5 times the mass of Jupiter, and we are finding significantly fewer and fewer things as you go below ten times the mass of Jupiter,” De Furio explained. “We find fewer five-Jupiter-mass objects than ten-Jupiter-mass objects, and we find way fewer three-Jupiter-mass objects than five-Jupiter-mass objects. We don’t really find any objects below two or three Jupiter masses, and we expect to see them if they are there, so we are hypothesizing that this could be the limit itself.”
Meyer added, “Webb, for the first time, has been able to probe up to and beyond that limit. If that limit is real, there really shouldn’t be any one-Jupiter-mass objects free-floating out in our Milky Way galaxy, unless they were formed as planets and then ejected out of a planetary system.”
Image B: Low Mass Objects within the Flame Nebula in Infrared Light
This near-infrared image of a portion of the Flame Nebula from NASA’s James Webb Space Telescope highlights three low-mass objects, seen in the insets to the right. These objects, which are much colder than protostars, require the sensitivity of Webb’s instruments to detect them. These objects were studied as part of an effort to explore the lowest mass limit of brown dwarfs within the Flame Nebula.
The Webb images represent light at wavelengths of 1.15 microns and 1.4 microns (filters F115W and F140M) as blue, 1.82 microns (F182M) as green, 3.6 microns (F360M) as orange, and 4.3 microns (F430M) as red. NASA, ESA, CSA, STScI, M. Meyer (University of Michigan) Building on Hubble’s Legacy
Brown dwarfs, given the difficulty of finding them, have a wealth of information to provide, particularly in star formation and planetary research given their similarities to both stars and planets. NASA’s Hubble Space Telescope has been on the hunt for these brown dwarfs for decades.
Even though Hubble can’t observe the brown dwarfs in the Flame Nebula to as low a mass as Webb can, it was crucial in identifying candidates for further study. This study is an example of how Webb took the baton—decades of Hubble data from the Orion Molecular Cloud Complex—and enabled in-depth research.
“It’s really difficult to do this work, looking at brown dwarfs down to even ten Jupiter masses, from the ground, especially in regions like this. And having existing Hubble data over the last 30 years or so allowed us to know that this is a really useful star-forming region to target. We needed to have Webb to be able to study this particular science topic,” said De Furio.
“It’s a quantum leap in our capabilities between understanding what was going on from Hubble. Webb is really opening an entirely new realm of possibilities, understanding these objects,” explained astronomer Massimo Robberto of the Space Telescope Science Institute.
This team is continuing to study the Flame Nebula, using Webb’s spectroscopic tools to further characterize the different objects within its dusty cocoon.
“There’s a big overlap between the things that could be planets and the things that are very, very low mass brown dwarfs,” Meyer stated. “And that’s our job in the next five years: to figure out which is which and why.”
These results are accepted for publication in The Astrophysical Journal Letters.
Image C (Animated): Flame Nebula (Hubble and Webb Comparison)
This animated image alternates between a Hubble Space Telescope and a James Webb Space Telescope observation of the Flame Nebula, a nearby star-forming nebula less than 1 million years old. In this comparison, three low-mass objects are highlighted. In Hubble’s observation, the low-mass objects are hidden by the region’s dense dust and gas. However, the objects are brought out in the Webb observation due to Webb’s sensitivity to faint infrared light. NASA, ESA, CSA, Alyssa Pagan (STScI) The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).
Downloads
Click any image to open a larger version.
View/Download all image products at all resolutions for this article from the Space Telescope Science Institute.
Media Contacts
Laura Betz – laura.e.betz@nasa.gov
NASA’s Goddard Space Flight Center, Greenbelt, Md.
Matthew Brown – mabrown@stsci.edu
Space Telescope Science Institute, Baltimore, Md.
Christine Pulliam – cpulliam@stsci.edu
Space Telescope Science Institute, Baltimore, Md.
Related Information
More Webb News
More Webb Images
Webb Science Themes
Webb Mission Page
Learn more about brown dwarf discoveries
Related For Kids
What is the Webb Telescope?
SpacePlace for Kids
En Español
Ciencia de la NASA
NASA en español
Space Place para niños
Keep Exploring Related Topics
James Webb Space Telescope
Webb is the premier observatory of the next decade, serving thousands of astronomers worldwide. It studies every phase in the…
Universe
Universe Stories
Stars Stories
Share
Details
Last Updated Mar 10, 2025 Editor Marty McCoy Contact Laura Betz laura.e.betz@nasa.gov Related Terms
James Webb Space Telescope (JWST) Astrophysics Brown Dwarfs Goddard Space Flight Center Science & Research Star-forming Nebulae The Universe View the full article
-
By NASA
5 min read
February’s Night Sky Notes: How Can You Help Curb Light Pollution?
Light pollution has long troubled astronomers, who generally shy away from deep sky observing under full Moon skies. The natural light from a bright Moon floods the sky and hides views of the Milky Way, dim galaxies and nebula, and shooting stars. In recent years, human-made light pollution has dramatically surpassed the interference of even a bright full Moon, and its effects are now noticeable to a great many people outside of the astronomical community. Harsh, bright white LED streetlights, while often more efficient and long-lasting, often create unexpected problems for communities replacing their old street lamps. Some notable concerns are increased glare and light trespass, less restful sleep, and disturbed nocturnal wildlife patterns. There is increasing awareness of just how much light is too much light at night. You don’t need to give in to despair over encroaching light pollution; you can join efforts to measure it, educate others, and even help stop or reduce the effects of light pollution in your community.
Before and after pictures of replacement lighting at the 6th Street Bridge over the Los Angeles River. The second picture shows improvements in some aspects of light pollution, as light is not directed to the sides and upwards from the upgraded fixtures, reducing skyglow. However, it also shows the use of brighter, whiter LEDs, which is not generally ideal, along with increased light bounce back from the road. City of Los Angeles Amateur astronomers and potential citizen scientists around the globe are invited to participate in the Globe at Night (GaN) program to measure light pollution. Measurements are taken by volunteers on a few scheduled days every month and submitted to their database to help create a comprehensive map of light pollution and its change over time. GaN volunteers can take and submit measurements using multiple methods ranging from low-tech naked-eye observations to high-tech sensors and smartphone apps.
Globe at Night citizen scientists can use the following methods to measure light pollution and submit their results:
Their own smartphone camera and dedicated app Manually measure light pollution using their own eyes and detailed charts of the constellations A dedicated light pollution measurement device called a Sky Quality Meter (SQM). The free GaN web app from any internet-connected device (which can also be used to submit their measurements from an SQM or printed-out star charts) Night Sky Network members joined a telecon with Connie Walker of Globe at Night in 2014 and had a lively discussion about the program’s history and how they can participate. The audio of the telecon, transcript, and links to additional resources can be found on their dedicated resource page.
Light pollution has been visible from space for a long time, but new LED lights are bright enough that they stand out from older street lights, even from orbit. The above photo was taken by astronaut Samantha Cristoforetti from the ISS cupola in 2015. The newly installed white LED lights in the center of the city of Milan are noticeably brighter than the lights in the surrounding neighborhoods. NASA/ESA DarkSky International has long been a champion in the fight against light pollution and a proponent of smart lighting design and policy. Their website (at darksky.org) provides many resources for amateur astronomers and other like-minded people to help communities understand the negative impacts of light pollution and how smart lighting policies can not only help bring the stars back to their night skies but make their streets safer by using smarter lighting with less glare. Communities and individuals find that their nighttime lighting choices can help save considerable sums of money when they decide to light their streets and homes “smarter, not brighter” with shielded, directional lighting, motion detectors, timers, and even choosing the proper “temperature” of new LED light replacements to avoid the harsh “pure white” glare that many new streetlamps possess. Their pages on community advocacy and on how to choose dark-sky-friendly lighting are extremely helpful and full of great information. There are even local chapters of the IDA in many communities made up of passionate advocates of dark skies.
DarkSky International has notably helped usher in “Dark Sky Places“, areas around the world that are protected from light pollution. “Dark Sky Parks“, in particular, provide visitors with incredible views of the Milky Way and are perfect places to spot the wonders of a meteor shower. These parks also perform a very important function, showing the public the wonders of a truly dark sky to many people who may have never before even seen a handful of stars in the sky, let alone the full, glorious spread of the Milky Way.
More research into the negative effects of light pollution on the health of humans and the environment is being conducted than ever before. Watching the nighttime light slowly increase in your neighborhood, combined with reading so much bad news, can indeed be disheartening! However, as awareness of light pollution and its negative effects increases, more people are becoming aware of the problem and want to be part of the solution. There is even an episode of PBS Kid’s SciGirls where the main characters help mitigate light pollution in their neighborhood!
Astronomy clubs are uniquely situated to help spread awareness of good lighting practices in their local communities in order to help mitigate light pollution. Take inspiration from Tucson, Arizona, and other dark sky-friendly communities that have adopted good lighting practices. Tucson even reduced its skyglow by 7% after its own citywide lighting conversion, proof that communities can bring the stars back with smart lighting choices.
Originally posted by Dave Prosper: November 2018
Last Updated by Kat Troche: January 2025
View the full article
-
By NASA
ESA/Hubble & NASA, C. Murray This NASA/ESA Hubble Space Telescope image features a dusty yet sparkling scene from one of the Milky Way’s satellite galaxies, the Large Magellanic Cloud. The Large Magellanic Cloud is a dwarf galaxy situated about 160,000 light-years away in the constellations Dorado and Mensa.
Despite being only 10–20% as massive as the Milky Way galaxy, the Large Magellanic Cloud contains some of the most impressive nearby star-forming regions. The scene pictured here is on the outskirts of the Tarantula Nebula, the largest and most productive star-forming region in the local universe. At its center, the Tarantula Nebula hosts the most massive stars known, weighing roughly 200 times the mass of the Sun.
The section of the nebula shown here features serene blue gas, brownish-orange dust patches, and a sprinkling of multicolored stars. The stars within and behind the dust clouds appear redder than those that are unobscured by dust. Dust absorbs and scatters blue light more than red light, allowing more of the red light to reach our telescopes, which makes the stars appear redder than they are. This image incorporates ultraviolet and infrared light as well as visible light. Using Hubble observations of dusty nebulae in the Large Magellanic Cloud and other galaxies, researchers can study these distant dust grains, helping them better understand the role that cosmic dust plays in the formation of new stars and planets.
View the full article
-
By NASA
NASA, ESA, and M. Wong (University of California – Berkeley); Processing: Gladys Kober (NASA/Catholic University of America) This NASA Hubble Space Telescope image shows the planet Jupiter in a color composite of ultraviolet wavelengths. Released on Nov. 3, 2023, in honor of Jupiter reaching opposition, which occurs when the planet and the Sun are in opposite sides of the sky, this view of the gas giant planet includes the iconic, massive storm called the “Great Red Spot.” Though the storm appears red to the human eye, in this ultraviolet image it appears darker because high altitude haze particles absorb light at these wavelengths. The reddish, wavy polar hazes are absorbing slightly less of this light due to differences in either particle size, composition, or altitude.
Learn more about Hubble and how this type of data can help us learn more about our universe.
Image credit: NASA, ESA, and M. Wong (University of California – Berkeley); Processing: Gladys Kober (NASA/Catholic University of America)
View the full article
-
By NASA
NASA Goddard MODIS Rapid Response Team During the morning of March 20, 2015, a total solar eclipse was visible from parts of Europe, and a partial solar eclipse from northern Africa and northern Asia. NASA’s Terra satellite passed over the Arctic Ocean on March 20 at 10:45 UTC (6:45 a.m. EDT) and captured the eclipse’s shadow over the clouds in the Arctic Ocean.
Terra launched 25 years ago on Dec. 18, 1999. Approximately the size of a small school bus, the Terra satellite carries five instruments that take coincident measurements of the Earth system: Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), Clouds and Earth’s Radiant Energy System (CERES), Multi-angle Imaging Spectroradiometer (MISR), Measurements of Pollution in the Troposphere (MOPITT), and Moderate Resolution Imaging Spectroradiometer (MODIS).
On Nov. 28, 2024, one of Terra’s power-transmitting shunt units failed. A response team reviewed Terra’s status and discussed potential impacts and options. Consequently, the team placed ASTER into Safe Mode. As a result, ASTER data are not currently being collected. All other instruments continue uninterrupted.
Image Credit: NASA Goddard MODIS Rapid Response Team
View the full article
-
-
Check out these Videos
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.