NASA’s Space Launch System (SLS) rocket is on the launch pad at NASA’s Kennedy Space Center in Florida and in final preparations for the Artemis I mission to the Moon. Now that our Moon rocket is almost ready for its debut flight, we wanted to take a look back at some of the most liked photographs of our SLS rocket coming together over the years.
We asked NASA photographers to share their favorite photos of the SLS rocket for Artemis I at different phases of testing, manufacturing, and assembly. Here are their stories behind the photos:
“On this day in March 2018, crews at NASA’s Marshall Space Flight Center in Huntsville, Alabama, transported the intertank structural test article off NASA’s Pegasus barge to the Load Test Annex test facility for qualification testing.” —Emmett Given, photographer, NASA’s Marshall Space Flight Center
“This is the liquid oxygen tank structural test article as it was moved from the Pegasus barge to the West Test Area at our Marshall Space Flight Center on July 9, 2019. The tank, which is structurally identical to its flight version, was subsequently placed in the test stand for structural testing several days later. I remember it being a blazing hot day!” —Fred Deaton, photographer, NASA’s Marshall Space Flight Center
“The large components of the SLS rocket’s core stage can make you forget that there are many hands-on tasks required to assemble a rocket, too. During the mating of the liquid hydrogen tank to the forward section of the rocket’s 212-foot-tall core stage in May 2019, technicians fastened 360 bolts to the circumference of the rocket. Images like this remind me of all the small parts that have to be installed with care, expertise, and precision to create one huge Moon rocket. Getting in close to capture the teammates that work tirelessly to make Artemis a success is one of the best parts of my job.” —Eric Bordelon, photographer, NASA’s Michoud Assembly Facility
“An incredible amount of precision goes into building a rocket, including making sure that each of our SLS rocket’s four RS-25 engines is aligned and integrated into the core stage correctly. In this image from October 2019, I attempted to illustrate the teamwork and communication happening as technicians at NASA’s Michoud Assembly Facility in New Orleans do their part to help land the first woman and the first person of color on the Moon through the Artemis missions. It’s rare to see the inside of a rocket – not as much for the NASA and Boeing engineers who manufacture and assemble a rocket stage!” —Jared Lyons, photographer, NASA’s Michoud Assembly Facility
“When the fully assembled and completed core stage left the Michoud factory in January 2020, employees took a “family photo” to mark the moment. Crews transported the flight hardware to NASA’s Pegasus barge on Jan. 8 in preparation for the core stage Green Run test series at NASA’s Stennis Space Center near Bay St. Louis, Mississippi. When I look at this photo, I am reminded of all of the hard work and countless hours the Michoud team put forth to build this next-generation Moon rocket. I am honored to be part of this family and to photograph historic moments like this for the Artemis program.” —Steven Seipel, MAF multimedia team lead, NASA’s Michoud Assembly Facility
“This photo shows workers at Stennis prepare to lift the SLS core stage into the B-2 Test Stand for the SLS Green Run test series in the early morning hours of Jan. 22, 2020. I started shooting the lift operation around midnight. During a break in the action at about 5:30 a.m., I was driving my government vehicle to the SSC gas station to fuel up, when I saw the first light breaking in the East and knew it was going to be a nice sunrise. I turned around and hurried back to the test stand, sweating that I might run out of gas. Luckily, I didn’t run out and was lucky enough to catch a beautiful Mississippi sunrise in the background, too.” —Danny Nowlin, photographer, NASA’s Stennis Space Center
“I like the symmetry in the video as it pushes toward the launch vehicle stage adapter. Teams at NASA’s Marshall Space Flight Center in Huntsville, Alabama, loaded the cone-shaped piece of flight hardware onto our Pegasus barge in July 2020 for delivery to NASA’s Kennedy Space Center in Florida. The one-point perspective puts the launch vehicle stage adapter at the center of attention, but, if you pay attention to the edges, you can see people working. It gives a sense of scale. This was the first time I got to walk around Pegasus and meet the crew that transport the deep space rocket hardware, too.” —Sam Lott, videographer, SLS Program at Marshall Space Flight Center
“This was my first time photographing a test at our Stennis Space Center, and I wasn't sure what to expect. I have photographed big events like professional football games, but I wasn't prepared for the awesome power unleashed by the Space Launch System’s core stage and four RS-25 engines during the Green Run hot fire test. Watching the sound wave ripple across the tall grass toward us, feeling the shock wave of ignition throughout my whole body, seeing the smoke curling up into the blue sky with rainbows hanging from the plume; all of it was as unforgettable as watching a football player hoist a trophy into the air.” —Michael DeMocker, photographer, NASA’s Michoud Assembly Facility
“When our SLS Moon rocket launches the agency’s Artemis I mission to the Moon, 10 CubeSats, or small satellites, are hitching a ride inside the rocket’s Orion stage adapter (OSA). BioSentinel is one of those CubeSats. BioSentinel’s microfluidics card, designed at NASA’s Ames Research Center in California’s Silicon Valley, will be used to study the impact of interplanetary space radiation on yeast. To me, this photo is a great combination of the scientific importance of Artemis I and the human touch of more than 100 engineers and scientists who have dedicated themselves to the mission over the years.” —Dominic Hart, photographer, NASA’s Ames Research Center
“I was in the employee viewing area at Kennedy when the integrated SLS rocket and Orion spacecraft was rolled out to the launchpad for its wet dress rehearsal in March 2022. I really like this photo because the sun is shining on Artemis I like a spotlight. The giant doors of the Vehicle Assembly Building are the red curtain that opened up the stage -- and the spotlight is striking the SLS because it’s the star of the show making its way to the launchpad. I remember thinking how cool that NASA Worm logo looked as well, so I wanted to capture that. It was so big that I had to turn my camera sideways because the lens I had wasn’t big enough to capture the whole thing.” —Brandon Hancock, videographer, SLS Program at NASA’s Marshall Space Flight Center
“I made this image while SLS and Orion atop the mobile launcher were nearing the end of their four-mile trek to the pad on crawler-transporter 2 ahead of launch. Small groups of employees were filtering in and out of the parking lot by the pad gate to take in the sight of the rocket’s arrival. The “We Are Going!” banner affixed to the gate in the foreground bears the handwritten names of agency employees and contractors who have worked to get the rocket and spacecraft ready for the Artemis I flight test. As we enter the final days before launch, I am proud to have made my small contribution to documenting the historic rollout for this launch to the Moon.” —Joel Kowsky, photographer, NASA Headquarters
NASA photographers will be on the ground covering the Artemis I launch. As they do, we’ll continue to share their photos on our official NASA channels.
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Our flying observatory, called SOFIA, is the world’s largest airborne observatory. It is a partnership with the German Aerospace Center (DLR). SOFIA studies the life cycle of stars, planets (including Pluto’s atmosphere), how interstellar dust can contribute to planet formation, analyzes the area around black holes, and identifies complex molecules in space.
1. A Telescope in an Airplane
SOFIA stands for the Stratospheric Observatory for Infrared Astronomy. It is a Boeing 747SP aircraft that carries a 100-inch telescope to observe the universe while flying between 38,000 and 45,000 feet – the layer of Earth’s atmosphere called the stratosphere.
2. The Short Aircraft Means Long Flights
SP stands for “special performance.” The plane is 47 feet shorter than a standard 747, so it’s lighter and can fly greater distances. Each observing flight lasts 10-12 hours.
3. It Flies with A Hole in the Side of the Plane…
The telescope is behind a door that opens when SOFIA reaches altitude so astronomers on board can study the universe. The kind of light SOFIA observes, infrared, is blocked by almost all materials, so engineers designed the side of the aircraft to direct air up-and-over the open cavity, ensuring a smooth flight.
4. …But the Cabin is Pressurized!
A wall, called a pressure bulkhead, was added between the telescope and the cabin so the team inside the aircraft stays comfortable and safe. Each flight has pilots, telescope operators, scientists, flight planners and mission crew aboard.
5. This Telescope Has to Fly
Water vapor in Earth’s atmosphere blocks infrared light from reaching the ground. Flying at more than 39,000 feet puts SOFIA above more than 99% of this vapor, allowing astronomers to study infrared light coming from space. The airborne observatory can carry heavier, more powerful instruments than space-based observatories because it is not limited by launch weight restrictions and solar power.
6. Studying the Invisible Universe
Humans cannot see what is beyond the rainbow of visible light. However, many interesting astronomical processes happen in the clouds of dust and gas that often surround the objects SOFIA studies, like newly forming stars. Infrared light can pass through these clouds, allowing astronomers to study what is happening inside these areas.
7. The German Telescope
The telescope was built our partner, the German Aerospace Center, DLR. It is made of a glass-ceramic material called Zerodur that does not change shape when exposed to extremely cold temperatures. The telescope has a honeycomb design, which reduces the weight by 80%, from 8,700 lb to 1,764 lb. (Note that the honeycomb design was only visible before the reflective aluminum coating was applied to the mirror’s surface).
8. ZigZag Flights with a Purpose
The telescope can move up and down, between 20-60 degrees above the horizon. But it can only move significantly left and right by turning the whole aircraft. Each new direction of the flight means astronomers are studying a new celestial object. SOFIA’s flight planners carefully map where the plane needs to fly to best observe each object planned for that night.
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Out of all the theories and fantasies created around blackholes, which of them, in your opinion, do you think could come closest to reality?
On June 17, our MAVEN (Mars Atmosphere and Volatile Evolution Mission) will celebrate 1,000 Earth days in orbit around the Red Planet.
Since its launch in November 2013 and its orbit insertion in September 2014, MAVEN has been exploring the upper atmosphere of Mars. MAVEN is bringing insight to how the sun stripped Mars of most of its atmosphere, turning a planet once possibly habitable to microbial life into a barren desert world.
10. Unprecedented Ultraviolet View of Mars
Revealing dynamic, previously invisible behavior, MAVEN was able to show the ultraviolet glow from the Martian atmosphere in unprecedented detail. Nightside images showed ultraviolet “nightglow” emission from nitric oxide. Nightglow is a common planetary phenomenon in which the sky faintly glows even in the complete absence of eternal light.
9. Key Features on the Loss of Atmosphere
Some particles from the solar wind are able to penetrate unexpectedly deep into the upper atmosphere, rather than being diverted around the planet by the Martian ionosphere. This penetration is allowed by chemical reactions in the ionosphere that turn the charged particles of the solar wind into neutral atoms that are then able to penetrate deeply.
8. Metal Ions
MAVEN made the first direct observations of a layer of metal ions in the Martian ionosphere, resulting from incoming interplanetary dust hitting the atmosphere. This layer is always present, but was enhanced dramatically by the close passage to Mars of Comet Siding Spring in October 2014.
7. Two New Types of Aurora
MAVEN has identified two new types of aurora, termed “diffuse” and “proton” aurora. Unlike how we think of most aurorae on Earth, these aurorae are unrelated to either a global or local magnetic field.
6. Cause of the Aurorae
These aurorae are caused by an influx of particles from the sun ejected by different types of solar storms. When particles from these storms hit the Martian atmosphere, they can also increase the rate of loss of gas to space, by a factor of ten or more.
5. Complex Interactions with Solar Wind
The interactions between the solar wind and the planet are unexpectedly complex. This results due to the lack of an intrinsic Martian magnetic field and the occurrence of small regions of magnetized crust that can affect the incoming solar wind on local and regional scales. The magnetosphere that results from the interactions varies on short timescales and is remarkably “lumpy” as a result.
4. Seasonal Hydrogen
After investigating the upper atmosphere of the Red Planet for a full Martian year, MAVEN determined that the escaping water does not always go gently into space. The spacecraft observed the full seasonal variation of hydrogen in the upper atmosphere, confirming that it varies by a factor of 10 throughout the year. The escape rate peaked when Mars was at its closest point to the sun and dropped off when the planet was farthest from the sun.
3. Gas Lost to Space
MAVEN has used measurements of the isotopes in the upper atmosphere (atoms of the same composition but having different mass) to determine how much gas has been lost through time. These measurements suggest that 2/3 or more of the gas has been lost to space.
2. Speed of Solar Wind Stripping Martian Atmosphere
MAVEN has measured the rate at which the sun and the solar wind are stripping gas from the top of the atmosphere to space today, along with details of the removal process. Extrapolation of the loss rates into the ancient past – when the solar ultraviolet light and the solar wind were more intense – indicates that large amounts of gas have been lost to space through time.
1. Martian Atmosphere Lost to Space
The Mars atmosphere has been stripped away by the sun and the solar wind over time, changing the climate from a warmer and wetter environment early in history to the cold, dry climate that we see today.
Maven will continue its observations and is now observing a second Martian year, looking at the ways that the seasonal cycles and the solar cycle affect the system.
For more information about MAVEN, visit: www.nasa.gov/maven
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Warm summer temperatures often lead to dangerous blooms of phytoplankton in lakes, reservoirs and along our coastlines. These toxin-containing aquatic organisms can sicken people and pets, contaminate drinking water, and force closures at boating and swimming sites.
In this image, a severe bloom of toxic blue-green algae is spreading across the western half of Lake Erie. Taken on July 30, 2019 by the Operational Land Imager on our Landsat 8 satellite, this image shows green patches where the bloom was most dense and where toxicity levels were unsafe for recreational activities. Around the time of this image, the bloom covered about 300 square miles of Lake Erie’s surface, roughly the size of New York City. By August 13, the bloom had doubled to more than 620 square miles. That’s eight times the size of Cleveland.
The dominant organism—a Microcystis cyanobacteria—produces the toxin microcystin, can cause liver damage, numbness, dizziness, and vomiting. On July 29, 2019, the National Oceanic Atmospheric Administration (NOAA) reported unsafe toxin concentrations in Lake Erie and have since advised people (and their pets) to stay away from areas where scum is forming on the water surface.
You can stay informed about harmful algal blooms using a new mobile app that will send you alerts on potentially harmful algal blooms in your area. Called CyAN, it's based on NASA satellite data of the color changes in lakes and other bodies of water. It serves as our eye-in-the-sky early warning system, alerting the public and local officials to when dangerous waters may be in bloom.
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The interstellar object 'Oumuamua perplexed scientists in October 2017 as it whipped past Earth at an unusually high speed. This mysterious visitor is the first object ever seen in our solar system that is known to have originated elsewhere. Here are five things we know and five things we don’t know about the first confirmed interstellar object to pass through our solar system.
The object known as 1I/2017 U1 (and nicknamed ‘Oumuamua) was traveling too fast (196,000 mph, that’s 54 miles per second or 87.3 kilometers per second) to have originated in our solar system. Comets and asteroids from within our solar system move at a slower speed, typically an average of 12 miles per second (19 kilometers per second) . In non-technical terms, 'Oumuamua is an “interstellar vagabond.”
Artist impression of the interstellar object ‘Oumuamua. Credit: ESA/Hubble, NASA, ESO, M. Kornmesser
'Oumuamua entered our solar system from the rough direction of the constellation Lyra, but it’s impossible to tell where it originally came from. Thousands of years ago, when 'Oumuamua started to wander from its parent planetary system, the stars were in a different position so it’s impossible to pinpoint its point of origin. It could have been wandering the galaxy for billions of years.
'Oumuamua is headed back out of our solar system and won’t be coming back. It’s rapidly headed in the direction of the constellation Pegasus and will cross the orbit of Neptune in about four years and cover one light year’s distance in about 11,000 years.
We’ve only seen it as a speck of light through a telescope (it is far away and less than half a mile in length), but its unique rotation leads us to believe that it’s elongated like a cigar, about 10 times longer than it is wide. We can’t see it anymore. Artist’s concepts are the best guesses at what it might look like.
A rapid response observing campaign allowed us to watch as 'Oumuamua got an unexpected boost in speed. The acceleration slightly changed its course from earlier predictions.
“This additional subtle force on ′Oumuamua likely is caused by jets of gaseous material expelled from its surface,” said Davide Farnocchia of the Center for Near Earth Object Studies (CNEOS) at NASA’s Jet Propulsion Laboratory. “This same kind of outgassing affects the motion of many comets in our solar system.”
Unusual variations in the comet’s brightness suggest it is rotating on more than one axis.
This illustration shows ‘Oumuamua racing toward the outskirts of our solar system. As the complex rotation of the object makes it difficult to determine the exact shape, there are many models of what it could look like. Credits: NASA/ESA/STScI
Comets in our solar system kick off lots of dust and gas when they get close to the Sun, but 'Oumuamua did not, which led observers to consider defining it as an asteroid.
Karen Meech, an astronomer at the University of Hawaii’s Institute of Astronomy, said small dust grains, present on the surface of most comets, may have eroded away during ′Oumuamua's long journey through interstellar space. "The more we study ′Oumuamua, the more exciting it gets." she said. It could be giving off gases that are harder to see than dust, but it’s impossible to know at this point.
Just not when. The discovery of an interstellar object has been anticipated for decades. The space between the stars probably has billions and billions of asteroids and comets roaming around independently. Scientists understood that inevitably, some of these small bodies would enter our own solar system. This interstellar visit by ‘Oumuamua reinforces our models of how planetary systems form.
After January 2018, 'Oumuamua was no longer visible to telescopes, even in space. But scientists continue to analyze the data gathered during the international observing campaign and crack open more mysteries about this unique interstellar visitor.
Because ′Oumuamua is the first interstellar object ever observed in our solar system, researchers caution that it’s difficult to draw general conclusions about this newly-discovered class of celestial bodies. Observations point to the possibility that other star systems regularly eject small comet-like objects and there should be more of them drifting among the stars. Future ground- and space-based surveys could detect more of these interstellar vagabonds, providing a larger sample for scientists to analyze. Adds, Karen Meech, an astronomer at the University of Hawaii’s Institute of Astronomy: “I can hardly wait for the next interstellar object!"
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Onboard the International Space Station, astronauts need to work out to maintain their bone density and muscle mass, usually exercising 2 hours every single day. Throughout the week, they exercise on three different pieces of equipment--a bike, a treadmill and the Advanced Restive Exercise Device (ARED).
All these devices are needed to keep an astronaut healthy.
However, deep-space vehicles like our Orion Spacecraft aren’t as roomy as station, so everything — including exercise equipment — needs to be downsized. The Miniature Exercise Device (MED-2) is getting us one step closer to being able to keep astronauts’ bodies healthy on long journeys to the moon, Mars and beyond.
MED-2 is a compact, all-in-one exercise device that we developed and will be launching to the space station Tuesday, March 22. Onboard the station, we’ll see how MED-2 will perform in microgravity and how it will need to be further adapted for our Journey to Mars. However, it’s already pretty well equipped for deep space missions.
1. It is an all-in-one exercise device, meaning it can do both aerobic and resistive workouts. When we go to Mars, the less equipment we need, the better.
2. It's incredibly light. The MED-2 weighs only 65 pounds, and every pound counts during space missions.
3. It has 5 - 350 pounds of resistance, despite weighing only 65 pounds. Astronauts don’t all lift the same amount, making the flexibility in MED-2’s “weights” essential.
4. It's tiny. (Hence its name Miniature Exercise Device.) Not only is MED-2 incredibly light, but it also won't take up a lot of space on any craft.
5. It powers itself. During an aerobic workout, the device charges, and then that power is used to run the resistive exercises. When traveling to space, it's good when nothing goes to waste, and now astronauts' workouts will help power the Journey to Mars.
MED-2 is only one of many devices and experiments flying on Orbital ATK’s Cygnus spacecraft. To find out more about the science on the space station, follow @ISS_Research and @Space_Station on Twitter.
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Roman's primary structure hangs from cables as it moves into the big clean room at NASA's Goddard Space Flight Center.
When you picture NASA’s most important creations, you probably think of a satellite, telescope, or maybe a rover. But what about the room they’re made in? Believe it or not, the room itself where these instruments are put together—a clean room—is pretty special.
A clean room is a space that protects technology from contamination. This is especially important when sending very sensitive items into space that even small particles could interfere with.
There are two main categories of contamination that we have to keep away from our instruments. The first is particulate contamination, like dust. The second is molecular contamination, which is more like oil or grease. Both types affect a telescope’s image quality, as well as the time it takes to capture imagery. Having too many particles on our instruments is like looking through a dirty window. A clean room makes for clean science!
Two technicians clean the floor of Goddard’s big clean room.
Our Goddard Space Flight Center in Greenbelt, Maryland has the largest clean room of its kind in the world. It’s as tall as an eight-story building and as wide as two basketball courts.
Goddard’s clean room has fewer than 3,000 micron-size particles per cubic meter of air. If you lined up all those tiny particles, they’d be no longer than a sesame seed. If those particles were the size of 16-inch (0.4-meter) inflatable beach balls, we’d find only 3,000 spread throughout the whole body of Mount Everest!
A clean room technician observes a sample under a microscope.
The clean room keeps out particles larger than five microns across, just seven percent of the width of an average human hair. It does this via special filters that remove around 99.97% of particles 0.3 microns and larger from incoming air. Six fans the size of school buses spin to keep air flowing and pressurize the room. Since the pressure inside is higher, the clean air keeps unclean air out when doors open.
A technician analyzes a sample under ultraviolet light.
In addition, anyone who enters must wear a “bunny suit” to keep their body particles away from the machinery. A bunny suit covers most of the person inside. Sometimes scientists have trouble recognizing each other while in the suits, but they do get to know each other’s mannerisms very well.
This illustration depicts the anatomy of a bunny suit, which covers clean room technicians from head to toe to protect sensitive technology.
The bunny suit is only the beginning: before putting it on, team members undergo a preparation routine involving a hairnet and an air shower. Fun fact – you’re not allowed to wear products like perfume, lotion, or deodorant. Even odors can transfer easily!
Six of Goddard’s clean room technicians (left to right: Daniel DaCosta, Jill Bender, Anne Martino, Leon Bailey, Frank D’Annunzio, and Josh Thomas).
It takes a lot of specialists to run Goddard’s clean room. There are 10 people on the Contamination Control Technician Team, 30 people on the Clean Room Engineering Team to cover all Goddard missions, and another 10 people on the Facilities Team to monitor the clean room itself. They check on its temperature, humidity, and particle counts.
A technician rinses critical hardware with isopropyl alcohol and separates the particulate and isopropyl alcohol to leave the particles on a membrane for microscopic analysis.
Besides the standard mopping and vacuuming, the team uses tools such as isopropyl alcohol, acetone, wipes, swabs, white light, and ultraviolet light. Plus, they have a particle monitor that uses a laser to measure air particle count and size.
The team keeping the clean room spotless plays an integral role in the success of NASA’s missions. So, the next time you have to clean your bedroom, consider yourself lucky that the stakes aren’t so high!
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“Only in the darkness can you see the stars.” —Martin Luther King, Jr. Pause for a moment and take in the vastness and beauty of our home planet captured from the vantage point of space. On this spaceship we call Earth, we are all in this together. 💙
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Astronomers used three of NASA's Great Observatories to capture this multiwavelength image showing galaxy cluster IDCS J1426.5+3508. It includes X-rays recorded by the Chandra X-ray Observatory in blue, visible light observed by the Hubble Space Telescope in green, and infrared light from the Spitzer Space Telescope in red. This rare galaxy cluster has important implications for understanding how these megastructures formed and evolved early in the universe.
Let’s add another item to your travel bucket list: the early universe! You don’t need the type of time machine you see in sci-fi movies, and you don’t have to worry about getting trapped in the past. You don’t even need to leave the comfort of your home! All you need is a powerful space-based telescope.
But let’s start small and work our way up to the farthest reaches of space. We’ll explain how it all works along the way.
This animation illustrates how fast light travels between Earth and the Moon. The farther light has to travel, the more noticeable its speed limit becomes.
The speed of light is superfast, but it isn’t infinite. It travels at about 186,000 miles (300 million meters) per second. That means that it takes time for the light from any object to reach our eyes. The farther it is, the more time it takes.
You can see nearby things basically in real time because the light travel time isn’t long enough to make a difference. Even if an object is 100 miles (161 kilometers) away, it takes just 0.0005 seconds for light to travel that far. But on astronomical scales, the effects become noticeable.
This infographic shows how long it takes light to travel to different planets in our solar system.
Within our solar system, light’s speed limit means it can take a while to communicate back and forth between spacecraft and ground stations on Earth. We see the Moon, Sun, and planets as they were slightly in the past, but it's not usually far enough back to be scientifically interesting.
As we peer farther out into our galaxy, we use light-years to talk about distances. Smaller units like miles or kilometers would be too overwhelming and we’d lose a sense of their meaning. One light-year – the distance light travels in a year – is nearly 6 trillion miles (9.5 trillion kilometers). And that’s just a tiny baby step into the cosmos.
The Sun’s closest neighboring star, Proxima Centauri, is 4.2 light-years away. That means we see it as it was about four years ago. Betelgeuse, a more distant (and more volatile) stellar neighbor, is around 700 light-years away. Because of light’s lag time, astronomers don’t know for sure whether this supergiant star is still there! It may have already blasted itself apart in a supernova explosion – but it probably has another 10,000 years or more to go.
What looks much like craggy mountains on a moonlit evening is actually the edge of a nearby, young, star-forming region NGC 3324 in the Carina Nebula. Captured in infrared light by the Near-Infrared Camera (NIRCam) on NASA’s James Webb Space Telescope, this image reveals previously obscured areas of star birth.
The Carina Nebula clocks in at 7,500 light-years away, which means the light we receive from it today began its journey about 3,000 years before the pyramids of Giza in Egypt were built! Many new stars there have undoubtedly been born by now, but their light may not reach Earth for thousands of years.
An artist’s concept of our Milky Way galaxy, with rough locations for the Sun and Carina nebula marked.
If we zoom way out, you can see that 7,500 light-years away is still pretty much within our neighborhood. Let’s look further back in time…
This stunning image by the NASA/ESA Hubble Space Telescope features the spiral galaxy NGC 5643. Looking this good isn’t easy; 30 different exposures, for a total of nine hours of observation time, together with Hubble’s high resolution and clarity, were needed to produce an image of such exquisite detail and beauty.
Peering outside our Milky Way galaxy transports us much further into the past. The Andromeda galaxy, our nearest large galactic neighbor, is about 2.5 million light-years away. And that’s still pretty close, as far as the universe goes. The image above shows the spiral galaxy NGC 5643, which is about 60 million light-years away! That means we see it as it was about 60 million years ago.
As telescopes look deeper into the universe, they capture snapshots in time from different cosmic eras. Astronomers can stitch those snapshots together to unravel things like galaxy evolution. The closest ones are more mature; we see them nearly as they truly are in the present day because their light doesn’t have to travel as far to reach us. We can’t rewind those galaxies (or our own), but we can get clues about how they likely developed. Looking at galaxies that are farther and farther away means seeing these star cities in ever earlier stages of development.
The farthest galaxies we can see are both old and young. They’re billions of years old now, and the light we receive from them is ancient since it took so long to traverse the cosmos. But since their light was emitted when the galaxies were young, it gives us a view of their infancy.
This animation is an artist’s concept of the big bang, with representations of the early universe and its expansion.
Comparing how fast objects at different distances are moving away opened up the biggest mystery in modern astronomy: cosmic acceleration. The universe was already expanding as a result of the big bang, but astronomers expected it to slow down over time. Instead, it’s speeding up!
The universe’s expansion makes it tricky to talk about the distances of the farthest objects. We often use lookback time, which is the amount of time it took for an object’s light to reach us. That’s simpler than using a literal distance, because an object that was 10 billion light-years away when it emitted the light we received from it would actually be more than 16 billion light-years away right now, due to the expansion of space. We can even see objects that are presently over 30 billion light-years from Earth, even though the universe is only about 14 billion years old.
This James Webb Space Telescope image shines with the light from galaxies that are more than 13.4 billion years old, dating back to less than 400 million years after the big bang.
Our James Webb Space Telescope has helped us time travel back more than 13.4 billion years, to when the universe was less than 400 million years old. When our Nancy Grace Roman Space Telescope launches in a few years, astronomers will pair its vast view of space with Webb’s zooming capabilities to study the early universe in better ways than ever before. And don’t worry – these telescopes will make plenty of pit stops along the way at other exciting cosmic destinations across space and time.
Learn more about the exciting science Roman will investigate on X and Facebook.
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The James Webb Space Telescope has just completed a successful first year of science. Let’s celebrate by seeing the birth of Sun-like stars in this brand-new image from the Webb telescope!
This is a small star-forming region in the Rho Ophiuchi cloud complex. At 390 light-years away, it's the closest star-forming region to Earth. There are around 50 young stars here, all of them similar in mass to the Sun, or smaller. The darkest areas are the densest, where thick dust cocoons still-forming protostars. Huge red bipolar jets of molecular hydrogen dominate the image, appearing horizontally across the upper third and vertically on the right. These occur when a star first bursts through its natal envelope of cosmic dust, shooting out a pair of opposing jets into space like a newborn first stretching her arms out into the world. In contrast, the star S1 has carved out a glowing cave of dust in the lower half of the image. It is the only star in the image that is significantly more massive than the Sun.
Thanks to Webb’s sensitive instruments, we get to witness moments like this at the beginning of a star’s life. One year in, Webb’s science mission is only just getting started. The second year of observations has already been selected, with plans to build on an exciting first year that exceeded expectations. Here’s to many more years of scientific discovery with Webb.
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Credits: NASA, ESA, CSA, STScI, Klaus Pontoppidan (STScI)
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