Strap In For A Tour Of The Milky Way

Solar System: Things to Know This Week

Learn more about our Deep Space Network, where to watch the Ursid meteor shower, Cassini’s ring-grazing at Saturn and more.

1. A Deep Space Anniversary

On Dec. 24, 1963, the Jet Propulsion Laboratory's Deep Space Information Facility was renamed the Deep Space Network. And, it’s been humanity's ear to the skies ever since.

+ History of the Deep Space Network 

2. Ursid Meteor Shower 

The best time to view the Ursids, radiating from Ursa Minor, or the little Dipper, will be from midnight on December 21 until about 1a.m. on December 22, before the moon rises.

3. At Saturn, the Ring-Grazing Continues

Our Cassini spacecraft has completed several orbits that take it just outside Saturn’s famous rings. The first ring-grazing orbit began on November 30. The spacecraft will repeat this feat 20 times, with only about a week between each ring-plane crossing.

+ Learn more

4. Preparing for the 2017 Total Solar Eclipse

Next year North America will see one of the most rare and spectacular of all sky events. Learn how to prepare.

+ 2017 Solar Eclipse Toolkit

5. Searching for Rare Asteroids

Our first mission to return an asteroid sample to Earth will be multitasking during its two-year outbound cruise to the asteroid Bennu. On February 9-20, OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer) will activate its onboard camera suite and begin its search for elusive “Trojan,” asteroids, constant companions to planets in our solar system as they orbit the sun, remaining near a stable point 60 degrees in front of or behind the planet. Because they constantly lead or follow in the same orbit, they will never collide with their companion planet.

Discover the full list of 10 things to know about our solar system this week HERE.

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Because space is vast and full of mysteries, NASA is developing a new rocket, a new spacecraft for astronauts and new facilities to launch them from. Our Space Launch System will be unlike any other rocket when it takes flight. It will be bigger, bolder and take astronauts and cargo farther than humankind has ever been -- to deep space destinations like the moon, a deep space gateway or even Mars. 

The Gravity-Slayer

When you plan to get to space, you use ice and fire. NASA’s Space Launch System uses four rocket engines in the center of the rocket and a pair of solid rocket boosters on opposite sides. All this power will propel the Space Launch System to gravity-slaying speeds of more than 17,000 miles per hour! These are the things we do for space exploration, the greatest adventure that ever was or will be.

It is Known

It is known that according to Newton’s third law, for every action there is an equal and opposite reaction. That’s how rocket propulsion works. Fuel burned in combustion chambers causes hot gases to shoot out the bottom of the engine nozzles. This propels the rocket upward. 

Steammaker

It is also known that when you combine hydrogen and oxygen you get: water. To help SLS get to space, the rocket’s four RS-25 engines shoot hydrogen and oxygen together at high speeds, making billowing clouds of steaming hot water vapor. The steam, funneled through the engine nozzles, expands with tremendous force and helps lift the rocket from the launchpad. 

RS-25: Ice King

It takes a lot of fuel (hydrogen) and a lot of oxygen to make a chemical reaction powerful enough to propel a rocket the size of a skyscraper off the launch pad. To fit more hydrogen and oxygen into the tanks in the center of the rocket where they’re stored, the hydrogen and oxygen are chilled to as low as -400 degrees Fahrenheit. At those temperatures, the gases become icy liquids. 

The Fire that Burns Against the Cold

The hydrogen-oxygen reaction inside the nozzles can reach temperatures up to 6,000 degrees Fahrenheit (alas, only Valyrian steel could withstand those temperatures)! To protect the nozzle from this heat, the icy hydrogen is pumped through more than a thousand small pipes on the outside of the nozzle to cool it. After the icy liquid protects the metal nozzles, it becomes fuel for the engines. 

Where is my FIRE?

The Space Launch System solid rocket boosters are the fire and the breakers of gravity’s chains. The solid rocket boosters’ fiery flight lasts for two minutes. They burn solid fuel that’s a potent mixture of chemicals the consistency of a rubber eraser. When the boosters light, hot gases and fire are unleashed at speeds up to three times the speed of sound, propelling the vehicle to gravity-slaying speed in seconds. 

Testing is Here

To make sure everything works on a rocket this big, it takes a lot of testing before the first flight. Rocket hardware is rolling off production lines all over the United States and being shipped to testing locations nationwide. Some of that test hardware includes replicas of the giant tanks that will hold the icy hydrogen and oxygen.

As Rare as Dragonglass

Other tests include firing the motor for the solid rocket boosters. The five-segment motor is the largest ever made for spaceflight and the part that contains the propellant that burns for two fiery, spectacular minutes. It’s common during ground test firings for the fiery exhaust to turn the sand in the Utah desert to glass.

Hold the Door

When all the hardware, software and avionics for SLS are ready, they will be shipped to Kennedy Space Center where the parts will be assembled to make the biggest rocket since the Saturn V. Then, technicians will stack Orion, NASA’s new spacecraft for taking astronauts to deep space, on top of SLS. All this work to assemble America’s new heavy-lift rocket and spacecraft will be done in the Vehicle Assembly Building -- one of the largest buildings in the world. Hold the door to the Vehicle Assembly Building open, because SLS and Orion are coming!

Learn more about our Journey to Mars here: https://www.nasa.gov/topics/journeytomars/index.html

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The Search for Starless Planets

While it’s familiar to us, our solar system may actually be a bit of an oddball. Our Milky Way galaxy is home to gigantic worlds with teeny-tiny orbits and planets that circle pairs of stars. We’ve even found planets that don’t orbit stars at all! Instead, they drift through the galaxy completely alone (unless they have a moon to keep them company). These lonely island worlds are called rogue planets.

Where do rogue planets come from?

The planet-building process can be pretty messy. Dust and gas around a star clump together to form larger and larger objects, like using a piece of play-dough to pick up other pieces.

Sometimes collisions and close encounters can fling a planet clear out of the gravitational grip of its parent star. Rogue planets may also form out in space on their own, like the way stars grow.

Seeing the invisible

We’ve discovered more than 4,000 exoplanets, but only a handful are rogue planets. That’s because they’re superhard to find! Rogue planets are almost completely invisible to us because they don’t shine like stars and space is inky black. It’s like looking for a black cat in a dark room without a flashlight.

Some planet-finding methods involve watching to see how orbiting planets affect their host star, but that doesn’t work for rogue planets because they’re off by themselves. Rogue planets are usually pretty cold too, so infrared telescopes can’t use their heat vision to spot them either.

So how can we find them? Astronomers use a cool cosmic quirk to detect them by their effect on starlight. When a rogue planet lines up with a more distant star from our vantage point, the planet bends and magnifies light from the star. This phenomenon, called microlensing, looks something like this:

Imagine you have a trampoline, a golf ball, and an invisible bowling ball. If you put the bowling ball on the trampoline, you could see how it made a dent in the fabric even if you couldn’t see the ball directly. And if you rolled the golf ball near it, it would change the golf ball’s path.

A rogue planet affects space the way the bowling ball warps the trampoline. When light from a distant star passes by a rogue planet, it curves around the invisible world (like how it curves around the star in the animation above). If astronomers on Earth were watching the star, they’d notice it briefly brighten. The shape and duration of this brightness spike lets them know a planet is there, even though they can’t see it.

Telescopes on the ground have to look through Earth’s turbulent atmosphere to search for rogue planets. But when our Nancy Grace Roman Space Telescope launches in the mid-2020s, it will give us a much better view of distant stars and rogue planets because it will be located way above Earth’s atmosphere — even higher than the Moon!

Other space telescopes would have to be really lucky to spot these one-in-a-million microlensing signals. But Roman will watch huge patches of the sky for months to catch these fleeting events.

Lessons from cosmic castaways

Scientists have come up with different models to explain how different planetary systems form and change over time, but we still don’t know which ones are right. The models make different predictions about rogue planets, so studying these isolated worlds can help us figure out which models work best.

When Roman spots little microlensing starlight blips, astronomers will be able to get a pretty good idea of the mass of the object that caused the signal from how long the blip lasts. Scientists expect the mission to detect hundreds of rogue planets that are as small as rocky Mars — about half the size of Earth — up to ones as big as gas giants, like Jupiter and Saturn.

By design, Roman is only going to search a small slice of the Milky Way for rogue planets. Scientists have come up with clever ways to use Roman’s future data to estimate how many rogue planets there are in the whole galaxy. This information will help us better understand whether our solar system is pretty normal or a bit of an oddball compared to the rest of our galaxy.

Roman will have such a wide field of view that it will be like going from looking at the cosmos through a peephole to looking through a floor-to-ceiling window. The mission will help us learn about all kinds of other cool things in addition to rogue planets, like dark energy and dark matter, that will help us understand much more about our place in space.

Learn more about the Roman Space Telescope at: https://roman.gsfc.nasa.gov/

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Whats the coolest thing u have seen or discovered???!!!! Like i mean cool as in something that made u nerd out! I used to want to work for nasa but found a love for teaching art instead so i find myself nersing out over the cool research yall put out! Much love from wise county texas!

Jupiter’s vibrant bands of light belts and dark regions appear primed for their close-up during our Juno spacecraft’s 10th flyby on Feb. 7. This flyby was a gravity science positioned pass. During orbits that highlight gravity experiments, Juno is positioned toward Earth in a way that allows both transmitters to downlink data in real-time to one of the antennas of our Deep Space Network. All of Juno’s science instruments and the spacecraft’s JunoCam were in operation during the flyby, collecting data that is now being returned to Earth. The science behind this beautifully choreographed image will help us understand the origin and structure of the planet beneath those lush, swirling clouds.

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

Testing Time for the SLS Engine Section

In schools across the country, many students just finished final exams. Now, part of the world’s most powerful rocket, the Space Launch System (SLS), is about to feel the pressure of testing time. The first SLS engine section has been moving slowly upriver from Michoud Assembly Facility near New Orleans, but once the barge Pegasus docks at our Marshall Space Flight Center in Huntsville, Alabama, the real strength test for the engine section will get started.

The engine section is the first of four of the major parts of the core stage that are being tested to make sure SLS is ready for the challenges of spaceflight.

The engine section is located at the bottom of the rocket. It has a couple of important jobs. It holds the four RS-25 liquid propellant engines, and it serves as one of two attach points for each of the twin solid propellant boosters. This first engine section will be used only for ground testing. 

Of all the major parts of the rocket, the engine section gets perhaps the roughest workout during launch. Millions of pounds of core stage are pushing down, while the engines are pushing up with millions of pounds of thrust, and the boosters are tugging at it from both sides. That’s a lot of stress. Maybe that’s why there’s a saying in the rocket business: “Test like you fly, and fly like you test.”

After it was welded at Michoud, technicians installed the thrust structure, engine supports and other internal equipment and loaded it aboard the Pegasus for shipment to Marshall.

Once used to transport space shuttle external tanks, Pegasus was modified for the longer SLS core stage by removing 115 feet out of the middle of the barge and added a new 165-foot section with a reinforced main deck. Now as long as a football field, Pegasus – with the help of two tugboats – will transport core stage test articles to Marshall Space Flight Center as well as completed core stages to Stennis Space Center in Mississippi for test firing and then to Kennedy Space Center for launch.

The test article has no engines, cabling, or computers, but it will replicate all the structures that will undergo the extreme physical forces of launch. The test article is more than 30 feet tall, and weighs about 70,000 pounds. About 3,200 sensors attached to the test article will measure the stress during 59 separate tests. Flight-like physical forces will be applied through simulators and adaptors standing in for the liquid hydrogen tank and RS-25 engines.

The test fixture that will surround and secure the engine section weighs about 1.5 million pounds and is taller than a 5-story building. Fifty-five big pistons called “load lines” will impart more than 4.5 million pounds of force vertically and more than 428,000 pounds from the side.

The engineers and their computer design tools say the engine section can handle the stress.  It’s the test team’s job prove that it can.

For more information about the powerful SLS rocket, check out: http://nasa.gov/SLS. 

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Sea Level Rise is on the Rise

As our planet warms, sea levels are rising around the world – and are doing so at an accelerating rate. Currently, global sea level is rising about an eighth of an inch every year.

That may seem insignificant, but it’s 30% more than when NASA launched its first satellite mission to measure ocean heights in 1992 – less than 30 years ago. And people already feel the impacts, as seemingly small increments of sea level rise become big problems along coastlines worldwide.

Higher global temperatures cause our seas to rise, but how? And why are seas rising at a faster and faster rate? There are two main reasons: melting ice and warming waters.

 The Ice We See Is Getting Pretty Thin

About two-thirds of global sea level rise comes from melting glaciers and ice sheets, the vast expanses of ice that cover Antarctica and Greenland. In Greenland, most of that ice melt is caused by warmer air temperatures that melt the upper surface of ice sheets, and when giant chunks of ice crack off of the ends of glaciers, adding to the ocean.

In Antarctica – where temperatures stay low year-round – most of the ice loss happens at the edges of glaciers. Warmer ocean water and warmer air meet at the glaciers’ edges, eating away at the floating ice sheets there.

NASA can measure these changes from space. With data from the Ice, Cloud and land Elevation Satellite-2, or ICESat-2, scientists can measure the height of ice sheets to within a fraction of an inch. Since 2006, an average of 318 gigatons of ice per year has melted from Greenland and Antarctica’s ice sheets. To get a sense of how big that is: just one gigaton is enough to cover New York City’s Central Park in ice 1,000 feet deep – almost as tall as the Chrysler Building.

With the Gravity Recovery and Climate Experiment Follow-On (GRACE-FO) mission -- a partnership with the German Research Centre for Geosciences -- scientists can calculate the mass of ice lost from these vast expanses across Greenland and Antarctica.

It’s not just glaciers in Antarctica and Greenland that are melting, though. Nearly all glaciers have been melting in the last decade, including those in Alaska, High Mountain Asia, South America, and the Canadian Arctic. Because these smaller glaciers are melting quickly, they contribute about the same amount to sea level rise as meltwater from massive ice sheets.

The Water’s Getting Warm

As seawater warms, it takes up more space. When water molecules get warmer, the atoms in those molecules vibrate faster, expanding the volume they take up. This phenomenon is called thermal expansion. It’s an incredibly tiny change in the size of a single water molecule, but added across all the water molecules in all of Earth’s oceans – a single drop contains well over a billion billion molecules – it accounts for about a third of global sea level rise.

So Much to See

While sea level is rising globally, it’s not the same across the planet. Sea levels are rising about an eighth of an inch per year on average worldwide. But some areas may see triple that rate, some may not observe any changes, and some may even experience a drop in sea level. These differences are due to ocean currents, mixing, upwelling of cold water from the deep ocean, winds, movements of heat and freshwater, and Earth’s gravitational pull moving water around. When ice melts from Greenland, for example, the drop in mass decreases the gravitational pull from the ice sheet, causing water to slosh to the shores of South America.

That’s where our view from space comes in. We’re launching Sentinel-6 Michael Freilich, an international partnership satellite, to continue our decades-long record of global sea level rise.

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

One Hot Year after Another

Globally, 2020 was the hottest year on record, effectively tying 2016, the previous record. Overall, Earth’s average temperature has risen more than 2 degrees Fahrenheit since the 1880s.

Temperatures are increasing due to human activities, specifically emissions of greenhouse gases, like carbon dioxide and methane. 

Heat and the energy it carries are what drive our planet: winds, weather, droughts, floods, and more are expressions of heat. The right amount of heat is even one of the things that makes life on Earth possible. But too much heat is changing the way our planet’s systems act.

My World’s on Fire

Higher temperatures drive longer, more intense fire seasons. As rain and snowfall patterns change, some regions are getting drier and more vulnerable to damage, setting the stage for more fires.

2020 saw several record-breaking fires, both in Australia in the beginning of the year, and in the western U.S. through northern summer and fall. Smoke from fires in both regions reached so high into the atmosphere that it formed clouds and continues to travel around the globe today.

In the Siberian Arctic, unusually high temperatures helped drive at least 19 fires in the region. More than half of them were burning peat soil -- decomposed organic materials -- that stores a lot of carbon. Peat fires release vast amounts of carbon into the atmosphere, potentially leading to even more warming.

The Water’s Getting Warm

It wasn’t just fire seasons setting records. 2020 had more named tropical storms in the Atlantic and more storms making landfall in the U.S. than any hurricane season on record.

Hurricanes rely on warm ocean water as fuel, and this year, the Atlantic provided. 30 named storms weren’t the only things that made this year’s hurricane season notable.

Storms like Eta, Delta, and Iota quickly changed from smaller, weaker tropical storms into more destructive hurricanes. This rapid intensification is complicated, but it’s likely that warmer, more humid weather -- a result of climate change -- helps drive it.

The Ice Is Getting Thin

Add enough heat, and even the biggest chunk of ice will melt. That’s true whether we’re talking about the ice cubes in your glass or the vast sheets of ice at our planet’s poles. Right now, the Arctic region is warming about three times faster than the rest of our planet, which has some major effects both locally and globally.

This year, Arctic sea ice hit a near-record low. Sea ice is actually made of frozen ocean water, and it grows and thaws with the seasons, typically reaching an annual minimum extent in September.

Warmer ocean water led to more ice melting this year, and 2020’s annual minimum extent continued a long trend of shrinking Arctic sea ice extent.

A Long Trend

We study Earth and how it’s changing from the ground, the sky, and space. Using data from sensors all around the planet, we calculate the global average temperature, working with our partners at NOAA.

Many other organizations also track global temperature using their own instruments and methods, and they all match remarkably well. The last seven years were the hottest seven years on record. Earth is getting warmer.

We also study the effects of increasing temperatures, like the melting sea ice and longer fire seasons mentioned above. Additionally, we can study the cause of climate change from space, with a bird’s eye view of increasing carbon in the atmosphere.

The planet is changing because of human activities. We’re working together with other agencies to monitor changes and understand what this means for people in the future.

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What from your job have you learned that you think everyone on Earth should know?

5 Unpredictable Things Swift Has Studied (and 1 It’s Still Looking For)

Our Neil Gehrels Swift Observatory — Swift for short — is celebrating its 20th anniversary! The satellite studies cosmic objects and events using visible, ultraviolet, X-ray, and gamma-ray light. Swift plays a key role in our efforts to observe our ever-changing universe. Here are a few cosmic surprises Swift has caught over the years — plus one scientists hope to see.

#BOAT

Swift was designed to detect and study gamma-ray bursts, the most powerful explosions in the universe. These bursts occur all over the sky without warning, with about one a day detected on average. They also usually last less than a minute – sometimes less than a few seconds – so you need a telescope like Swift that can quickly spot and precisely locate these new events.

In the fall of 2022, for example, Swift helped study a gamma-ray burst nicknamed the BOAT, or brightest of all time. The image above depicts X-rays Swift detected for 12 days after the initial flash. Dust in our galaxy scattered the X-ray light back to us, creating an extraordinary set of expanding rings.

Star meets black hole

Tidal disruptions happen when an unlucky star strays too close to a black hole. Gravitational forces break the star apart into a stream of gas, as seen above. Some of the gas escapes, but some swings back around the black hole and creates a disk of debris that orbits around it.

These events are rare. They only occur once every 10,000 to 100,000 years in a galaxy the size of our Milky Way. Astronomers can’t predict when or where they’ll pop up, but Swift’s quick reflexes have helped it observe several tidal disruption events in other galaxies over its 20-year career.

Active galaxies

Usually, we think of galaxies – and most other things in the universe – as changing so slowly that we can’t see the changes. But about 10% of the universe’s galaxies are active, which means their black hole-powered centers are very bright and have a lot going on. They can produce high-speed particle jets or flares of light. Sometimes scientists can catch and watch these real-time changes.

For example, for several years starting in 2018, Swift and other telescopes observed changes in a galaxy’s X-ray and ultraviolet light that led them to think the galaxy’s magnetic field had flipped 180 degrees.

Magnetic star remnants

Magnetars are a type of neutron star, a very dense leftover of a massive star that exploded in a supernova. Magnetars have the strongest magnetic fields we know of — up to 10 trillion times more intense than a refrigerator magnet and a thousand times stronger than a typical neutron star’s.

Occasionally, magnetars experience outbursts related to sudden changes in their magnetic fields that can last for months or even years. Swift detected such an outburst from a magnetar in 2020. The satellite’s X-ray observations helped scientists determine that the city-sized object was rotating once every 10.4 seconds.

Comets

Swift has also studied comets in our own solar system. Comets are town-sized snowballs of frozen gases, rock, and dust. When one gets close to our Sun, it heats up and spews dust and gases into a giant glowing halo.

In 2019, Swift watched a comet called 2I/Borisov. Using ultraviolet light, scientists calculated that Borisov lost enough water to fill 92 Olympic-size swimming pools! (Another interesting fact about Borisov: Astronomers think it came from outside our solar system.)

What's next for Swift?

Swift has studied a lot of cool events and objects over its two decades, but there are still a few events scientists are hoping it’ll see.

Swift is an important part of a new era of astrophysics called multimessenger astronomy, which is where scientists use light, particles, and space-time ripples called gravitational waves to study different aspects of cosmic events.

In 2017, Swift and other observatories detected light and gravitational waves from the same event, a gamma-ray burst, for the first time. But what astronomers really want is to detect all three messengers from the same event.

As Swift enters its 20th year, it’ll keep watching the ever-changing sky.

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