Members Can Post Anonymously On This Site
Incredible Aurora / Northern Lights Time-lapse
-
Similar Topics
-
By NASA
Did you know some of the brightest sources of light in the sky come from the regions around black holes in the centers of galaxies? It sounds a little contradictory, but it’s true! They may not look bright to our eyes, but satellites have spotted oodles of them across the universe.
One of those satellites is NASA’s Fermi Gamma-ray Space Telescope. Fermi has found thousands of these kinds of galaxies since it launched in 2008, and there are many more out there!
To view this video please enable JavaScript, and consider upgrading to a web browser that
supports HTML5 video
Watch a cosmic gamma-ray fireworks show in this animation using just a year of data from the Large Area Telescope (LAT) aboard NASA’s Fermi Gamma-ray Space Telescope. Each object’s magenta circle grows as it brightens and shrinks as it dims. The yellow circle represents the Sun following its apparent annual path across the sky. The animation shows a subset of the LAT gamma-ray records available for more than 1,500 objects in a continually updated repository. Over 90% of these sources are a type of galaxy called a blazar, powered by the activity of a supermassive black hole. NASA’s Marshall Space Flight Center/Daniel Kocevski Black holes are regions of space that have so much gravity that nothing — not light, not particles, nada — can escape. Most galaxies have supermassive black holes at their centers, and these black holes are hundreds of thousands to billions of times the mass of our Sun. In active galactic nuclei (also called “AGN” for short, or just “active galaxies”) the central region is stuffed with gas and dust that’s constantly falling toward the black hole. As the gas and dust fall, they start to spin and form a disk. Because of the friction and other forces at work, the spinning disk starts to heat up.
This composite view of the active galaxy Markarian 573 combines X-ray data (blue) from NASA’s Chandra X-ray Observatory and radio observations (purple) from the Karl G. Jansky Very Large Array in New Mexico with a visible light image (gold) from the Hubble Space Telescope. Markarian 573 is an active galaxy that has two cones of emission streaming away from the supermassive black hole at its center. X-ray: NASA/CXC/SAO/A.Paggi et al; Optical: NASA/STScI; Radio: NSF/NRAO/VLA The disk’s heat gets emitted as light, but not just wavelengths of it that we can see with our eyes. We detect light from AGN across the entire electromagnetic spectrum, from the more familiar radio and optical waves through to the more exotic X-rays and gamma rays, which we need special telescopes to spot.
In the heart of an active galaxy, matter falling toward a supermassive black hole creates jets of particles traveling near the speed of light as shown in this artist’s concept. NASA/Goddard Space Flight Center Conceptual Image Lab About one in 10 AGN beam out jets of energetic particles, which are traveling almost as fast as light. Scientists are studying these jets to try to understand how black holes — which pull everything in with their huge amounts of gravity — somehow provide the energy needed to propel the particles in these jets.
This artist’s concept shows two views of the active galaxy TXS 0128+554, located around 500 million light-years away. Left: The galaxy’s central jets appear as they would if we viewed them both at the same angle. The black hole, embedded in a disk of dust and gas, launches a pair of particle jets traveling at nearly the speed of light. Scientists think gamma rays (magenta) detected by NASA’s Fermi Gamma-ray Space Telescope originate from the base of these jets. As the jets collide with material surrounding the galaxy, they form identical lobes seen at radio wavelengths (orange). The jets experienced two distinct bouts of activity, which created the gap between the lobes and the black hole. Right: The galaxy appears in its actual orientation, with its jets tipped out of our line of sight by about 50 degrees. NASA’s Goddard Space Flight Center Many of the ways we tell one type of AGN from another depend on how they’re oriented from our point of view. With radio galaxies, for example, we see the jets from the side as they’re beaming vast amounts of energy into space. Then there’s blazars, which are a type of AGN that have a jet that is pointed almost directly at Earth, which makes the AGN particularly bright.
Blazar 3C 279’s historic gamma-ray flare in 2015 can be seen in this image from the Large Area Telescope on NASA’s Fermi satellite. During the flare, the blazar outshone the Vela pulsar, usually the brightest object in the gamma-ray sky. NASA/DOE/Fermi LAT Collaboration Fermi has been searching the sky for gamma ray sources since 2008. More than half of the sources it has found have been blazars. Gamma rays are useful because they can tell us a lot about how particles accelerate and how they interact with their environment.
So why do we care about AGN? We know that some AGN formed early in the history of the universe. With their enormous power, they almost certainly affected how the universe changed over time. By discovering how AGN work, we can understand better how the universe came to be the way it is now.
Share
Details
Last Updated Apr 30, 2025 Related Terms
The Universe Active Galaxies Fermi Gamma-Ray Space Telescope Galaxies Explore More
8 min read How to Contribute to Citizen Science with NASA
Article
24 hours ago
6 min read Where Does Gold Come From? NASA Data Has Clues
Article
1 day ago
2 min read Hubble Visits Glittering Cluster, Capturing Its Ultraviolet Light
Article
5 days ago
Keep Exploring Discover More Topics From NASA
Galaxies
Black Holes
Telescopes 101
Fermi
View the full article
-
By NASA
2 min read
Preparations for Next Moonwalk Simulations Underway (and Underwater)
How can I see the northern lights?
To see the northern lights, you need to be in the right place at the right time.
Auroras are the result of charged particles and magnetism from the Sun called space weather dancing with the Earth’s magnetic field. And they happen far above the clouds. So you need clear skies, good space weather at your latitude and the higher, more polar you can be, the better. You need a lot of patience and some luck is always helpful.
A smartphone can also really help confirm whether you saw a little bit of kind of dim aurora, because cameras are more sensitive than our eyes.
The best months to see aurorae, statistically, are March and September. The best times to be looking are around midnight, but sometimes when the Sun is super active, it can happen any time from sunset to sunrise.
You can also increase your chances by learning more about space weather data and a great place to do that is at the NOAA Space Weather Prediction Center.
You can also check out my project, Aurorasaurus.org, where we have free alerts that are based on your location and we offer information about how to interpret the data. And you can also report and tell us if you were able to see aurora or not and that helps others.
One last tip is finding a safe, dark sky viewing location with a great view of the northern horizon that’s near you.
[END VIDEO TRANSCRIPT]
Full Episode List
Full YouTube Playlist
Share
Details
Last Updated Mar 26, 2025 Related Terms
Science Mission Directorate Auroras Heliophysics Planetary Science Division The Solar System The Sun Explore More
6 min read How NASA’s Perseverance Is Helping Prepare Astronauts for Mars
Article 1 hour ago 6 min read NASA’s Webb Captures Neptune’s Auroras For First Time
Long-sought auroral glow finally emerges under Webb’s powerful gaze For the first time, NASA’s James…
Article 7 hours ago 5 min read NASA’s Parker Solar Probe Team Wins 2024 Collier Trophy
The innovative team of engineers and scientists from NASA, the Johns Hopkins Applied Physics Laboratory…
Article 22 hours ago Keep Exploring Discover Related Topics
Missions
Humans in Space
Climate Change
Solar System
View the full article
-
-
-
By NASA
4 min read
NASA to Launch Three Rockets from Alaska in Single Aurora Experiment
Three NASA-funded rockets are set to launch from Poker Flat Research Range in Fairbanks, Alaska, in an experiment that seeks to reveal how auroral substorms affect the behavior and composition of Earth’s far upper atmosphere.
The experiment’s outcome could upend a long-held theory about the aurora’s interaction with the thermosphere. It may also improve space weather forecasting, critical as the world becomes increasingly reliant on satellite-based devices such as GPS units in everyday life.
Colorful ribbons of aurora sway with geomagnetic activity above the launch pads of Poker Flat Research Range. NASA/Rachel Lense The University of Alaska Fairbanks (UAF) Geophysical Institute owns Poker Flat, located 20 miles north of Fairbanks, and operates it under a contract with NASA’s Wallops Flight Facility in Virginia, which is part of NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
The experiment, titled Auroral Waves Excited by Substorm Onset Magnetic Events, or AWESOME, features one four-stage rocket and two two-stage rockets all launching in an approximately three-hour period.
Colorful vapor tracers from the largest of the three rockets should be visible across much of northern Alaska. The launch window is March 24 through April 6.
The mission, led by Mark Conde, a space physics professor at UAF, involves about a dozen UAF graduate student researchers at several ground monitoring sites in Alaska at Utqiagvik, Kaktovik, Toolik Lake, Eagle, and Venetie, as well as Poker Flat. NASA delivers, assembles, tests, and launches the rockets.
“Our experiment asks the question, when the aurora goes berserk and dumps a bunch of heat in the atmosphere, how much of that heat is spent transporting the air upward in a continuous convective plume and how much of that heat results in not only vertical but also horizontal oscillations in the atmosphere?” Conde said.
Confirming which process is dominant will reveal the breadth of the mixing and the related changes in the thin air’s characteristics.
“Change in composition of the atmosphere has consequences,” Conde said. “And we need to know the extent of those consequences.”
Most of the thermosphere, which reaches from about 50 to 350 miles above the surface, is what scientists call “convectively stable.” That means minimal vertical motion of air, because the warmer air is already at the top, due to absorption of solar radiation.
A technician with NASA’s Wallops Flight Facility sounding rocket office works on one of the payload sections of the rocket that will launch for the AWESOME campaign. NASA/Lee Wingfield When auroral substorms inject energy and momentum into the middle and lower thermosphere (roughly 60 to 125 miles up), it upsets that stability. That leads to one prevailing theory — that the substorms’ heat is what causes the vertical-motion churn of the thermosphere.
Conde believes instead that acoustic-buoyancy waves are the dominant mixing force and that vertical convection has a much lesser role. Because acoustic-buoyancy waves travel vertically and horizontally from where the aurora hits, the aurora-caused atmospheric changes could be occurring over a much broader area than currently believed.
Better prediction of impacts from those changes is the AWESOME mission’s practical goal.
“I believe our experiment will lead to a simpler and more accurate method of space weather prediction,” Conde said.
Two two-stage, 42-foot Terrier-Improved Malemute rockets are planned to respectively launch about 15 minutes and an hour after an auroral substorm begins. A four-stage, 70-foot Black Brant XII rocket is planned to launch about five minutes after the second rocket.
The first two rockets will release tracers at altitudes of 50 and 110 miles to detect wind movement and wave oscillations. The third rocket will release tracers at five altitudes from 68 to 155 miles.
Pink, blue, and white vapor traces should be visible from the third rocket for 10 to 20 minutes. Launches must occur in the dawn hours, with sunlight hitting the upper altitudes to activate the vapor tracers from the first rocket but darkness at the surface so ground cameras can photograph the tracers’ response to air movement.
By Rod Boyce
University of Alaska Fairbanks Geophysical Institute
NASA Media Contact: Sarah Frazier
Share
Details
Last Updated Mar 21, 2025 Related Terms
Sounding Rockets Goddard Space Flight Center Heliophysics Heliophysics Division Heliophysics Research Program Science & Research Science Mission Directorate Sounding Rockets Program Uncategorized Wallops Flight Facility Explore More
2 min read Hubble Captures a Neighbor’s Colorful Clouds
Article
7 hours ago
11 min read The Earth Observer Editor’s Corner: January–March 2025
Article
24 hours ago
5 min read Celebrating 25 Years of Terra
Article
24 hours ago
Keep Exploring Discover Related Topics
Missions
Humans in Space
Climate Change
Solar System
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.