Say Hello To Globular cluster 47 Tucanae 👋

We Need Your Help to Find STEVE

Glowing in mostly purple and green colors, a newly discovered celestial phenomenon is sparking the interest of scientists, photographers and astronauts. The display was initially discovered by a group of citizen scientists who took pictures of the unusual lights and playfully named them "Steve."

When scientists got involved and learned more about these purples and greens, they wanted to keep the name as an homage to its initial name and citizen science discoverers. Now it is STEVE, short for Strong Thermal Emission Velocity Enhancement.

Credit: ©Megan Hoffman

STEVE occurs closer to the equator than where most aurora appear – for example, Southern Canada – in areas known as the sub-auroral zone. Because auroral activity in this zone is not well researched, studying STEVE will help scientists learn about the chemical and physical processes going on there. This helps us paint a better picture of how Earth's magnetic fields function and interact with charged particles in space. Ultimately, scientists can use this information to better understand the space weather near Earth, which can interfere with satellites and communications signals.

Want to become a citizen scientist and help us learn more about STEVE? You can submit your photos to a citizen science project called Aurorasaurus, funded by NASA and the National Science Foundation. Aurorasaurus tracks appearances of auroras – and now STEVE – around the world through reports and photographs submitted via a mobile app and on aurorasaurus.org.

Here are six tips from what we have learned so far to help you spot STEVE:

1. STEVE is a very narrow arc, aligned East-West, and extends for hundreds or thousands of miles.

Credit: ©Megan Hoffman 

2. STEVE mostly emits light in purple hues. Sometimes the phenomenon is accompanied by a short-lived, rapidly evolving green picket fence structure (example below).

Credit: ©Megan Hoffman 

3. STEVE can last 20 minutes to an hour.

4. STEVE appears closer to the equator than where normal – often green – auroras appear. It appears approximately 5-10° further south in the Northern hemisphere. This means it could appear overhead at latitudes similar to Calgary, Canada. The phenomenon has been reported from the United Kingdom, Canada, Alaska, northern US states, and New Zealand.

5. STEVE has only been spotted so far in the presence of an aurora (but auroras often occur without STEVE). Scientists are investigating to learn more about how the two phenomena are connected. 

6. STEVE may only appear in certain seasons. It was not observed from October 2016 to February 2017. It also was not seen from October 2017 to February 2018.

Credit: ©Megan Hoffman 

STEVE (and aurora) sightings can be reported at www.aurorasaurus.org or with the Aurorasaurus free mobile apps on Android and iOS. Anyone can sign up, receive alerts, and submit reports for free.

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.

What is like to be surrounded by the stars and darkness? Is it terrifying or calming?

That Time We Flew Past Pluto…

Two years ago today (July 14), our New Horizons spacecraft made its closest flyby of Pluto…collecting images and science that revealed a geologically complex world. Data from this mission are helping us understand worlds at the edge of our solar system.

The spacecraft is now venturing deeper into the distant, mysterious Kuiper Belt…a relic of solar system formation…to reach its next target. On New Year’s Day 2019, New Horizons will zoom past a Kuiper Belt object known as 2014 MU69.

The Kuiper Belt is a disc-shaped region of icy bodies – including dwarf planets such as Pluto – and comets beyond the orbit of Neptune. It extends from about 30 to 55 Astronomical Units (an AU is the distance from the sun to Earth) and is probably populated with hundreds of thousands of icy bodies larger than 62 miles across, and an estimated trillion or more comets.

Nearly a billion miles beyond Pluto, you may be asking how the spacecraft will function for the 2014 MU69 flyby. Well, New Horizons was originally designed to fly far beyond the Pluto system and explore deeper into the Kuiper Belt. 

The spacecraft carries extra hydrazine fuel for the flyby; its communications system is designed to work from beyond Pluto; its power system is designed to operate for many more years; and its scientific instruments were designed to operate in light levels much lower than it will experience during the 2014 MU69 flyby.

What have we learned about Pluto since its historic flyby in 2015?

During its encounter, the New Horizons spacecraft collected more than 1,200 images of Pluto and tens of gigabits of data. The intensive downlinking of information took about a year to return to Earth! Here are a few things we’ve discovered:

Pluto Has a Heart

This image captured by New Horizons around 16 hours before its closest approach shows Pluto’s “heart.” This stunning image of one of its most dominant features shows us that the heart’s diameter is about the same distance as from Denver to Chicago. This image also showed us that Pluto is a complex world with incredible geological diversity.

Icy Plains

Pluto’s vast icy plain, informally called Sputnik Planitia, resembles frozen mud cracks on Earth. It has a broken surface of irregularly-shaped segments, bordered by what appear to be shallow troughs.

Majestic Mountains

Images from the spacecraft display chaotically jumbled mountains that only add to the complexity of Pluto’s geography. The rugged, icy mountains are as tall as 11,000 feet high.

Color Variations

This high-resolution enhanced color view of Pluto combines blue, red and infrared images taken by the New Horizons spacecraft. The surface of Pluto has a remarkable range of subtle color variations. Many landforms have their own distinct colors, telling a complex geological and climatological story.

Foggy Haze and Blue Atmosphere

Images returned from the New Horizons spacecraft have also revealed that Pluto’s global atmospheric haze has many more layers than scientists realized. The haze even creates a twilight effect that softly illuminates nightside terrain near sunset, which makes them visible to the cameras aboard the spacecraft.

Water Ice

New Horizons detected numerous small, exposed regions of water ice on Pluto. Scientists are eager to understand why water appears exactly where it does, and not in other places.

Stay updated on New Horizons findings by visiting the New Horizons page. You can also keep track of Pluto News on Twitter via @NASANewHorizons.

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com

Bend Your Mind With Special Relativity

Ever dreamed of traveling nearly as fast as light? Zipping across the universe to check out the sights seems like it could be fun. But, not so fast. There are a few things you should know before you jump into your rocket. At near the speed of light, the day-to-day physics we know on Earth need a few modifications. And if you’re thinking Albert Einstein will be entering this equation, you’re right!

We live our daily lives using what scientists call Newtonian physics, as in Isaac Newton, the guy who had the proverbial apple fall on his head. Imagine that you are on a sidewalk, watching your friend walk toward the front of a bus as it drives away. The bus is moving at 30 mph. Your friend walks at 3 mph. To you, your friend is moving at 33 mph — you simply add the two speeds together. (The 30 mph the bus is moving plus 3 mph that your friend is moving inside the bus.) This is a simple example of Newtonian physics.

However, imagine that your friend on the bus turns on a flashlight, and you both measure the speed of its light. You would both measure it to be moving at 670 million mph (or 1 billion kilometers per hour) — this is the speed of light. Even though the flashlight is with your friend on the moving bus, you still both measure the speed of light to be exactly the same. Suddenly you see how Einstein’s physics is different from Newton’s.

This prediction was a key part of Einstein’s special theory of relativity: The speed of light is the same for any observer, no matter their relative speed. This leads to many seemingly weird effects.  

Before talking about those surprising effects, it’s good to take a moment to talk about point of view. For the rest of this discussion, we’ll assume that you’re at rest — sitting in one spot in space, not moving. And your friend is on a rocket ship that you measure to be traveling at 90% the speed of light. Neither of you is changing speed or direction. Scientists give this a fancy name — an “inertial frame of reference.”

With the stage set, now we can talk about a couple of super-weird effects of traveling near the speed of light. Relativity messes with simple things like distance and time, doing stuff that might blow your mind!

Let’s say you have a stick that is 36 inches long (91 centimeters). Your friend on the rocket doesn’t know the stick’s length, so they measure it by comparing it to a ruler they have as they zoom past you. They find your stick is just 16 inches (40 centimeters) long — less than half the length you measured! This effect is called length contraction. And if they were moving even faster, your friend would measure your stick to be even shorter. The cool thing about relativity is that both of those measurements are right! We see these effects in particle physics with fast-moving particles.

If your friend was traveling to our nearest neighbor star, Proxima Centauri, how far would they think it was? From Earth, we measure Proxima Centauri to be 4.2 light-years away (where one light-year is the distance light travels in a year, or about 5.8 trillion miles). However, your friend, who is traveling at 90% the speed of light in the rocket, would measure the distance between Earth and Proxima Centauri to be just over 1.8 light-years.

That’s just length … let’s talk about time!

Now let’s say you and your friend on the rocket have identical synchronized clocks. When your friend reaches Proxima Centauri, they send you a signal, telling you how long their trip took them. Their clock says the trip took just over two years. Remember, they measure the distance to be 1.8 light-years. However, you would see that your clock, which stayed at rest with you, says the trip took 4.7 years — more than twice as long!

This effect is called time dilation — time on moving clocks appears to tick slower.

None of this accounts for your friend accelerating their rocket or stopping at Proxima Centauri. All of this math gets more complicated if you and your friend were speeding up, slowing down, or changing directions. For instance, if your friend slowed down to stop at Proxima Centauri, they would have aged less than you on their trip!

Now you’re ready for a few tips on near-light-speed travel! Watch the video below for more.

Now, if you need to relax a bit after this whirlwind, near-light-speed trip, you can grab our coloring pages of scenes from the video. And if you enjoyed the trip, download a postcard to send to a friend. Finally, if you want to explore more of the wonders of the universe, follow NASA Universe on Facebook and Twitter.

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com

Love Letters from Space

Love is in the air, and it’s out in space too! The universe is full of amazing chemistry, cosmic couples held together by gravitational attraction, and stars pulsing like beating hearts.

Celestial objects send out messages we can detect if we know how to listen for them. Our upcoming Nancy Grace Roman Space Telescope will help us scour the skies for all kinds of star-crossed signals.

Celestial Conversation Hearts

Communication is key for any relationship – including our relationship with space. Different telescopes are tuned to pick up different messages from across the universe, and combining them helps us learn even more. Roman is designed to see some visible light – the type of light our eyes can see, featured in the photo above from a ground-based telescope – in addition to longer wavelengths, called infrared. That will help us peer through clouds of dust and across immense stretches of space.

Other telescopes can see different types of light, and some detectors can even help us study cosmic rays, ghostly neutrinos, and ripples in space called gravitational waves.

Intergalactic Hugs

This visible and near-infrared image from the Hubble Space Telescope captures two hearts locked in a cosmic embrace. Known as the Antennae Galaxies, this pair’s love burns bright. The two spiral galaxies are merging together, igniting the birth of brand new baby stars.

Stellar nurseries are often very dusty places, which can make it hard to tell what’s going on. But since Roman can peer through dust, it will help us see stars in their infancy. And Roman’s large view of space coupled with its sharp, deep imaging will help us study how galaxy mergers have evolved since the early universe.

Cosmic Chemistry

Those stars are destined to create new chemistry, forging elements and scattering them into space as they live, die, and merge together. Roman will help us understand the cosmic era when stars first began forming. The mission will help scientists learn more about how elements were created and distributed throughout galaxies.

Did you know that U and I (uranium and iodine) were both made from merging neutron stars? Speaking of which…

Fatal Attraction

When two neutron stars come together in a marriage of sorts, it creates some spectacular fireworks! While they start out as stellar sweethearts, these and some other types of cosmic couples are fated for devastating breakups.

When a white dwarf – the leftover core from a Sun-like star that ran out of fuel – steals material from its companion, it can throw everything off balance and lead to a cataclysmic explosion. Studying these outbursts, called type Ia supernovae, led to the discovery that the expansion of the universe is speeding up. Roman will scan the skies for these exploding stars to help us figure out what’s causing the expansion to accelerate – a mystery known as dark energy.

Going Solo

Plenty of things in our galaxy are single, including hundreds of millions of stellar-mass black holes and trillions of “rogue” planets. These objects are effectively invisible – dark objects lost in the inky void of space – but Roman will see them thanks to wrinkles in space-time.

Anything with mass warps the fabric of space-time. So when an intervening object nearly aligns with a background star from our vantage point, light from the star curves as it travels through the warped space-time around the nearer object. The object acts like a natural lens, focusing and amplifying the background star’s light.

Thanks to this observational effect, which makes stars appear to temporarily pulse brighter, Roman will reveal all kinds of things we’d never be able to see otherwise.

Roman is nearly ready to set its sights on so many celestial spectacles. Follow along with the mission’s build progress in this interactive virtual tour of the observatory, and check out these space-themed Valentine’s Day cards.

Make sure to follow us on Tumblr for your regular dose of space!

Congratulations to the Winner of the Name the Artemis Moonikin Challenge!

Congratulations to Campos! After a very close competition among eight different names, the people have decided: Commander Moonikin Campos is launching on Artemis I, our first uncrewed flight test of the Space Launch System rocket and Orion spacecraft around the Moon later this year.

The name Campos is a dedication to Arturo Campos, electrical power subsystem manager for the Apollo 13 lunar module. He is remembered as not only a key player instrumental to the Apollo 13 crew’s safe return home, but as a champion for equality in the workplace. The final bracket challenge was between Campos and Delos, a reference to the island where Apollo and Artemis were born, according to Greek mythology.

The Moonikin is a male-bodied manikin previously used in Orion vibration tests. Campos will occupy the commander’s seat inside and wear a first-generation Orion Crew Survival System — a spacesuit Artemis astronauts will wear during launch, entry, and other dynamic phases of their missions. Campos' seat will be outfitted with sensors under the headrest and behind the seat to record acceleration and vibration data throughout the mission. Data from the Moonikin’s experience will inform us how to protect astronauts during Artemis II, the first mission around the Moon with crew in more than 50 years.

The Moonikin is one of three passengers flying in place of crew aboard Orion on the mission to test the systems that will take astronauts to the Moon for the next generation of exploration. Two female-bodied model human torsos, called phantoms, will also be aboard Orion. Zohar and Helga, the phantoms named by the Israel Space Agency and the German Aerospace Center respectively, will support an investigation called the Matroshka AstroRad Radiation Experiment to provide data on radiation levels during lunar missions.

Campos, Zohar, and Helga are really excited to begin the journey around the Moon and back. The Artemis I mission will be one of the first steps to establishing a long-term presence on and around the Moon under Artemis, and will help us prepare for humanity's next giant leap — sending the first astronauts to Mars.

Be sure to follow Campos, Zohar, and Helga on their journey by following @NASAArtemis on Facebook, Twitter, and Instagram. Make sure to follow us on Tumblr for your regular dose of space!

A Wrinkle in Space-Time: The Eclipse That “Proved” Einstein Right

One hundred years ago a total solar eclipse turned an obscure scientist into a household name. You might have heard of him — his name is Albert Einstein. But how did a solar eclipse propel him to fame?

First, it would be good to know a couple things about general relativity. (Wait, don’t go! We’ll keep this to the basics!)

A decade before he finished general relativity, Einstein published his special theory of relativity, which demonstrates how space and time are interwoven as a single structure he dubbed “space-time.” General relativity extended the foundation of special relativity to include gravity. Einstein realized that gravitational fields can be understood as bends and curves in space-time that affect the motions of objects including stars, planets — and even light.

For everyday situations the centuries-old description of gravity by Isaac Newton does just fine. However, general relativity must be accounted for when we study places with strong gravity, like black holes or neutron stars, or when we need very precise measurements, like pinpointing a position on Earth to within a few feet. That makes it hard to test!

A prediction of general relativity is that light passing by an object feels a slight "tug", causing the light's path to bend slightly. The more mass the object has, the more the light will be deflected. This sets up one of the tests that Einstein suggested — measuring how starlight bends around the Sun, the strongest source of gravity in our neighborhood. Starlight that passes near the edge of the Sun on its way to Earth is deflected, altering by a small amount where those stars appear to be. How much? By about the width of a dime if you saw it at a mile and a quarter away! But how can you observe faint stars near the brilliant Sun? During a total solar eclipse!

That’s where the May 29, 1919, total solar eclipse comes in. Two teams were dispatched to locations in the path of totality — the places on Earth where the Moon will appear to completely cover the face of the Sun during an eclipse. One team went to South America and another to Africa.

On eclipse day, the sky vexed both teams, with rain in Africa and clouds in South America. The teams had only mere minutes of totality during which to take their photographs, or they would lose the opportunity until the next total solar eclipse in 1921! However, the weather cleared at both sites long enough for the teams to take images of the stars during totality.

The teams took two sets of photographs of the same patch of sky – one set during the eclipse and another set a few months before or after, when the Sun was out of the way. By comparing these two sets of photographs, researchers could see if the apparent star positions changed as predicted by Einstein. This is shown with the effect exaggerated in the image above.

A few months after the eclipse, when the teams sorted out their measurements, the results demonstrated that general relativity correctly predicted the positions of the stars. Newspapers across the globe announced that the controversial theory was proven (even though that’s not quite how science works). It was this success that propelled Einstein into the public eye.

The solar eclipse wasn’t the first test of general relativity. For more than two centuries, astronomers had known that Mercury’s orbit was a little off. Its perihelion — the point during its orbit when it is closest to the Sun — was changing faster than Newton’s laws predicted. General relativity easily explains it, though, because Mercury is so close to the Sun that its orbit is affected by the Sun’s dent in space-time, causing the discrepancy.  

In fact, we still test general relativity today under different conditions and in different situations to see whether or not it holds up. So far, it has passed every test we’ve thrown at it.

Curious to know where we need general relativity to understand objects in space? Tune into our Tumblr tomorrow to find out!

You can also read more about how our understanding of the universe has changed during the past 100 years, from Einstein's formulation of gravity through the discovery of dark energy in our Cosmic Times newspaper series.

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.

What in the Universe is an Exoplanet?

Simply put, an exoplanet is a planet that orbits another star. 

All of the planets in our solar system orbit around the Sun. Planets that orbit around other stars outside our solar system are called exoplanets.

Just because a planet orbits a star (like Earth) does not mean that it is automatically stable for life. The planet must be within the habitable zone, which is the area around a star in which water has the potential to be liquid…aka not so close that all the water would evaporate, and not too far away where all the water would freeze.

Exoplanets are very hard to see directly with telescopes. They are hidden by the bright glare of the stars they orbit. So, astronomers use other ways to detect and study these distant planets by looking at the effects these planets have on the stars they orbit.

One way to search for exoplanets is to look for "wobbly" stars. A star that has planets doesn’t orbit perfectly around its center. From far away, this off-center orbit makes the star look like it’s wobbling. Hundreds of planets have been discovered using this method. However, only big planets—like Jupiter, or even larger—can be seen this way. Smaller Earth-like planets are much harder to find because they create only small wobbles that are hard to detect.

How can we find Earth-like planets in other solar systems?

In 2009, we launched a spacecraft called Kepler to look for exoplanets. Kepler looked for planets in a wide range of sizes and orbits. And these planets orbited around stars that varied in size and temperature.

Kepler detected exoplanets using something called the transit method. When a planet passes in front of its star, it’s called a transit. As the planet transits in front of the star, it blocks out a little bit of the star's light. That means a star will look a little less bright when the planet passes in front of it. Astronomers can observe how the brightness of the star changes during a transit. This can help them figure out the size of the planet.

By studying the time between transits, astronomers can also find out how far away the planet is from its star. This tells us something about the planet’s temperature. If a planet is just the right temperature, it could contain liquid water—an important ingredient for life.

So far, thousands of planets have been discovered by the Kepler mission.

We now know that exoplanets are very common in the universe. And future missions have been planned to discover many more!

Next month, we’re launching an explorer-class planet finder — the Transiting Exoplanet Survey Satellite (TESS). This mission will search the entire sky for exoplanets — planets outside our solar system that orbit sun-like stars.

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.

Happy Earth Day!

It’s Earth Day, and what better way to celebrate than to show you a glimpse of our various efforts to protect and understand our home planet.

We’re able to use the vantage point of space to improve our understanding of the most complex planet we’ve seen yet…EARTH! Our Earth-observing satellites, airborne research and field campaigns are designed to observe our planet’s dynamic systems – oceans, ice sheets, forests and atmosphere – and improve our ability to understand how our planet is changing.

Here are a few of our Earth campaigns that you should know about:

KORUS-AQ (Korea U.S. - Air Quality)

Our KORUS-AQ airborne science experiment taking to the field in South Korea is part of a long-term, international project to take air quality observations from space to the next level and better inform decisions on how to protect the air we breathe. Field missions like KORUS-AQ provide opportunities to test and improve the instruments using simulators that measure above and below aircraft, while helping to infer what people breathe at the surface.

This campaign will assess air quality across urban, rural and coastal South Korea using observations from aircraft, ground sites, ships and satellites to test air quality models and remote sensing methods.

NAAMES (North Atlantic Aerosols and Marine Ecosystems Study)

Our NAAMES study takes to the sea and air in order to study how the world’s largest plankton bloom gives rise to small organic particles that influence clouds and climate. This study will collect data during ship and aircraft measurement campaigns and combine the data with continuous satellite and ocean sensor readings.

IceBridge

Operation IceBridge is our survey of polar ice, and is kicking off its eighth spring Arctic campaign. This mission has gathered large volumes of data on changes in the elevation of the ice sheet and its internal structure. It’s readings of the thickness of sea ice and its snow cover have helped scientists improve forecasts for the summer melt season and have enhanced the understanding of variations in ice thickness distribution from year to year.

GPM (Global Precipitation Measurement)

GPM is an international satellite mission to provide next-generation observations of rain and snow worldwide every three hours. We launched this mission with the Japanese Aerospace Exploration Agency (JAXA) in 2014. GPM contributes to advancing our understanding of Earth’s water and energy cycles, improves forecasting of extreme events and extends current capabilities of using satellite precipitation information to directly benefit society.

Find information about all of our Earth-studying missions HERE. 

Celebrate Earth Day with Us!

Want to participate in Earth Day with us? Share on social media what you’re doing to celebrate and improve our home planet. We’ll be sharing aspects of a “day in the life” of our Earth science research. Use the tag #24Seven to join the conversation. Details: http://www.nasa.gov/press-release/nasa-announces-earth-day-24seven-social-media-event

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com

Solar System: Things to Know This Week

Our solar system is huge, let us break it down for you. Here are a few things you should know this week: 

1. Closeup of a King

For the first time since it entered orbit around Jupiter in July, our Juno spacecraft has flown close to the king of planets—this time with its eyes wide open. During the long, initial orbit, Juno mission managers spent time checking out the spacecraft "from stem to stern," but the science instruments were turned off as a precaution. During this latest pass, Juno's camera and other instruments were collecting data the whole time. Initial reports show that all went well, and the team has released a new close-up view that Juno captured of Jupiter's north polar region. We can expect to see more close-up pictures of Jupiter and other data this week.

+Check in with Juno

2. Getting Ready to Rocket

Our OSIRIS-REx mission leaves Earth next week, the first leg of a journey that will take it out to an asteroid called Bennu. The mission will map the asteroid, study its properties in detail, then collect a physical sample to send back home to Earth. The ambitious endeavor is slated to start off on Sept. 8.

+See what it takes to prep for a deep space launch

3. New Moon Rising

The Lunar Reconnaissance Orbiter (LRO) has already mapped the entire surface of Earth's moon in brilliant detail, but the mission isn't over yet. Lunar explorers still have questions, and LRO is poised to help answer them.

+See what’s next for the mission

4. A Mock-Eclipse Now

We don't have to wait until next year to see the moon cross in front of the sun. From its vantage point in deep space, our Solar Dynamics Observatory (SDO) sometimes sees just that. Such an event is expected on Sept. 1.

+See the latest sun pictures from SDO

5. Jupiter’s Cousins

Our galaxy is home to a bewildering variety of Jupiter-like worlds: hot ones, cold ones, giant versions of our own giant, pint-sized pretenders only half as big around. Astronomers say that in our galaxy alone, a billion or more such Jupiter-like worlds could be orbiting stars other than our sun. And we can use them to gain a better understanding of our solar system and our galactic environment, including the prospects for finding life.

Want to learn more? Read our full list of the 10 things to know this week about the solar system HERE. 

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com