Solar System: Things To Know This Week

Which Landsat Image Do You Love?

Feeling competitive? We’ve got a game for you to play in! Tournament Earth: The Landsat Games is happening right now, and as we get to the final entries, the competition is heating up.

You can help us pick the winner by voting for one of the remaining four Landsat images of our home planet! Our competition started with 32 images, divided into categories by what they show: land, water, ice & snow, and human impact.

So, what do you think? Which one of these images is going for gold?

Land

First up, we have an image of the Markha River and surrounding Central Siberian Plateau, acquired in 2020 by Landsat 8. The hypnotic undulations of striping across the landscape carried this image to victory over the rest of the Land images -- a particularly tough category, given that these images all come from Landsat.

Water

It’s not all land, though! The bright blues and greens of this false-color image of the Atchafalaya Delta in Louisiana helped carry it to victory in the Water category. The image, taken in 2020 by Landsat 8, shows a region that’s subject to erosion of land by wind and rising sea levels.

Ice & Snow

Brrr! Did it get cold in here? That’s the finalist from the Ice and Snow category, an image of sea ice around Russia’s New Siberian Islands. The image, collected by Landsat 8 in June 2016, shows sea ice during its annual seasonal breakup.

Human Impact

Humans have been shaping the planet around us for hundreds of years. Some changes, like rice fields in the Sacramento Valley, are visible from space. Landsat 8 collected this false-color image of flooded rice fields in December 2018.

So, now it’s up to you! Which image is your favorite? There can only be one winner of Tournament Earth: The Landsat Games. Get your vote in, and then get ready to watch as we launch the next Landsat satellite, Landsat 9, in September.

The Landsat mission is a partnership between us at NASA and the U.S. Geological Survey. Together, we’ve been using Landsat satellites to collect nearly 50 years of images of our home planet.

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When you first saw Earth from all the way up in space, what were your first thoughts? Did it change the way you viewed things?

Questions coming up from….

@maybeinanotherworld: JWST IS HAPPENING! How are all of you feeling about this?

@Anonymous: How powerful is this telescope, exactly?

@Anonymous: Why are the mirrors on it yellow?

@foeofcolor: How long is this estimated to last for? Like how long will it be able to function in space by estimates?

Is your only job helping astronauts and satellites or does NASA do other thing too?

@lmndmlk: How many hours a day do you spend working?

Why Webb Needs to Chill

Our massive James Webb Space Telescope just recently emerged from about 100 days of cryogenic testing to make sure it can work perfectly at incredibly cold temperatures when it’s in deep space. 

How cold did it get and why? Here’s the whole scoop...

Webb is a giant infrared space telescope that we are currently building. It was designed to see things that other telescopes, even the amazing Hubble Space Telescope, can’t see.  

Webb’s giant 6.5-meter diameter primary mirror is part of what gives it superior vision, and it’s coated in gold to optimize it for seeing infrared light.  

Why do we want to see infrared light?

Lots of stuff in space emits infrared light, so being able to observe it gives us another tool for understanding the universe. For example, sometimes dust obscures the light from objects we want to study – but if we can see the heat they are emitting, we can still “see” the objects to study them.

It’s like if you were to stick your arm inside a garbage bag. You might not be able to see your arm with your eyes – but if you had an infrared camera, it could see the heat of your arm right through the cooler plastic bag.

Credit: NASA/IPAC

With a powerful infrared space telescope, we can see stars and planets forming inside clouds of dust and gas.

We can also see the very first stars and galaxies that formed in the early universe. These objects are so far away that…well, we haven’t actually been able to see them yet. Also, their light has been shifted from visible light to infrared because the universe is expanding, and as the distances between the galaxies stretch, the light from them also stretches towards redder wavelengths. 

We call this phenomena “redshift.”  This means that for us, these objects can be quite dim at visible wavelengths, but bright at infrared ones. With a powerful enough infrared telescope, we can see these never-before-seen objects.

We can also study the atmospheres of planets orbiting other stars. Many of the elements and molecules we want to study in planetary atmospheres have characteristic signatures in the infrared.

Because infrared light comes from objects that are warm, in order to detect the super faint heat signals of things that are really, really far away, the telescope itself has to be very cold. How cold does the telescope have to be? Webb’s operating temperature is under 50K (or -370F/-223 C). As a comparison, water freezes at 273K (or 32 F/0 C).

How do we keep the telescope that cold? 

Because there is no atmosphere in space, as long as you can keep something out of the Sun, it will get very cold. So Webb, as a whole, doesn’t need freezers or coolers - instead it has a giant sunshield that keeps it in the shade. (We do have one instrument on Webb that does have a cryocooler because it needs to operate at 7K.)

Also, we have to be careful that no nearby bright things can shine into the telescope – Webb is so sensitive to faint infrared light, that bright light could essentially blind it. The sunshield is able to protect the telescope from the light and heat of the Earth and Moon, as well as the Sun.  

Out at what we call the Second Lagrange point, where the telescope will orbit the Sun in line with the Earth, the sunshield is able to always block the light from bright objects like the Earth, Sun and Moon.

How do we make sure it all works in space? 

By lots of testing on the ground before we launch it. Every piece of the telescope was designed to work at the cold temperatures it will operate at in space and was tested in simulated space conditions. The mirrors were tested at cryogenic temperatures after every phase of their manufacturing process.

The instruments went through multiple cryogenic tests at our Goddard Space Flight Center in Maryland.

Once the telescope (instruments and optics) was assembled, it even underwent a full end-to-end test in our Johnson Space Center’s giant cryogenic chamber, to ensure the whole system will work perfectly in space.  

What’s next for Webb? 

It will move to Northrop Grumman where it will be mated to the sunshield, as well as the spacecraft bus, which provides support functions like electrical power, attitude control, thermal control, communications, data handling and propulsion to the spacecraft.

Learn more about the James Webb Space Telescope HERE, or follow the mission on Facebook, Twitter and Instagram.

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

When you went into space for the first time, what was it like? Were you nervous?

It’s May the 4th: Are Star Wars Planets Real?

Look at what we’ve found so far.

Is your favorite Star Wars planet a desert world or an ice planet or a jungle moon?

It’s possible that your favorite planet exists right here in our galaxy. Astronomers have found over 3,700 planets around other stars, called “exoplanets.”

Some of these alien worlds could be very similar to arid Tatooine, watery Scarif and even frozen Hoth, according to our scientists.

Find out if your planet exists in a galaxy far, far away or all around you. And May the Fourth be with you!

Planets With Two Suns

From Luke Skywalker’s home world Tatooine, you can stand in the orange glow of a double sunset. The same could said for Kepler-16b, a cold gas giant roughly the size of Saturn, that orbits two stars. Kepler-16b was the Kepler telescope’s first discovery of a planet in a “circumbinary” orbit (that is, circling both stars, as opposed to just one, in a double star system). 

The best part is that Tatooine aka Kepler-16b was just the first. It has family. A LOT of family. Half the stars in our galaxy are pairs, rather than single stars like our sun. If every star has at least one planet, that’s billions of worlds with two suns. Billions! Maybe waiting for life to be found on them.

Desert Worlds

Mars is a cold desert planet in our solar system, and we have plenty of examples of scorching hot planets in our galaxy (like Kepler-10b), which orbits its star in less than a day)! Scientists think that if there are other habitable planets in the galaxy, they’re more likely to be desert planets than ocean worlds. That’s because ocean worlds freeze when they’re too far from their star, or boil off their water if they’re too close, potentially making them unlivable. Perhaps, it’s not so weird that both Luke Skywalker and Rey grew up on planets that look a lot alike.

Ice Planets

An icy super-Earth named OGLE-2005-BLG-390Lb reminded scientists so much of the frozen Rebel base they nicknamed it “Hoth,” after its frozen temperature of minus 364 degrees Fahrenheit. Another Hoth-like planet was discovered in April 2017; an Earth-mass icy world orbiting its star at the same distance as Earth orbits the sun. But its star is so faint, the surface of OGLE-2016-BLG-1195Lb is probably colder than Pluto.

Forest worlds

Both the forest moon of Endor and Takodana, the home of Han Solo’s favorite cantina in “Force Awakens,” are green like our home planet. But astrobiologists think that plant life on other worlds could be red, black, or even rainbow-colored!

In February 2017, the Spitzer Space Telescope discovered seven Earth-sized planets in the same system, orbiting the tiny red star TRAPPIST-1.

The light from a red star, also known as an M dwarf, is dim and mostly in the infrared spectrum (as opposed to the visible spectrum we see with our sun). And that could mean plants with wildly different colors than what we’re used to seeing on Earth. Or, it could mean animals that see in the near-infrared.

What About Moons?

In Star Wars, Endor, the planet with the cute Ewoks, is actually a habitable moon of a gas giant. Now, we’re looking for life on the moons of our own gas giants. Saturn’s moon Enceladus or Jupiter’s moon Europa are ocean worlds that may well support life. Our Cassini spacecraft explored the Saturn system and its moons, before the mission ended in 2017. Watch the video and learn more about the missions’s findings.

And Beyond

The next few years will see the launch of a new generation of spacecraft to search for planets around other stars. Our TESS spacecraft launched in April 2018, and will discover new exoplanets by the end of the year. The James Webb Space Telescope is slated to launch in 2020. That’s one step closer to finding life.

You might want to take our ‘Star Wars: Fact or Fiction?’ quiz. Try it! Based on your score you may obtain the title of Padawan, Jedi Knight, or even Jedi Master! 

You don’t need to visit a galaxy far, far away to find wondrous worlds. Just visit this one ... there’s plenty to see.

Discover more about exoplanets here: https://exoplanets.nasa.gov/

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

For Earth Day, we’re inviting you to take a moment to celebrate our wonderful water world, Earth. As far as we know, our Blue Marble is the only place in the universe with life, and that life depends on water. Snap a photo of yourself outside and tag it #GlobalSelfie – bonus points if your selfie features your favorite body of water! http://go.nasa.gov/3xFt0H0

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

What is it Like to be a NASA Intern?

We asked prospective interns that follow us on social media what questions they had for our current interns. 

You asked…they answered! Let’s take a look:

Answer: “Yes, sometimes astronauts request to run through the International Space Station simulation that we have using the hyper-reality lab.”

Answer: “Persistence is the key to getting your first NASA internship. Work hard, study hard, keep applying and persevere.”

Answer: “NASA is looking for passionate, smart and curious, full-time students, who are U.S. citizens, at least 16 years of age and have a minimum 3.0 GPA.”

Answer: “In addition to STEM majors, NASA has many opportunities for students studying business, photography, English, graphics and public relations.”

Answer: “The highlight has been the chance to learn a lot more about embedded systems and coding for them, and just seeing how everyone’s efforts in lab come together for our small part in the AVIRIS-NG project.”

Answer: Yes! Here at the Kennedy Space Center is where all the action takes place. Check out the schedule on our website!”

Answer:  “There are 10 NASA field centers and they all accept interns.”

Answer: "Yes, we do! I am currently working in tech development for an X-ray telescope that is launched into space to take pictures of our galaxy.”

Answer: “The greatest thing I’ve learned as a NASA intern is to not be afraid of failing and to get involved in any way you can. NASA is a very welcoming environment that offers a lot of opportunities for its interns to learn.”

Answer: My favorite experience from being a NASA intern is meeting people from all around the world and being exposed to the different cultures.”

Want to become a NASA intern? Visit intern.nasa.gov to learn about the open opportunities and follow @NASAInterns on Twitter and Facebook for regular updates!

Watch the full story on NASA Snapchat or Instagram until it expires on April 6.

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