.@ScottAdamsSays

50 years ago, three Apollo astronauts rode this 363 foot tall rocket, the Saturn V, embarking on one of the greatest missions of mankind – to step foot on another world. On July 20, 1969, astronauts Buzz Aldrin, Michael Collins and Neil Armstrong made history when they arrived at the Moon. Thanks to the Saturn V rocket, we were able to complete this epic feat, returning to the lunar surface a total of six times. The six missions that landed on the Moon returned a wealth of scientific data and almost 400 kilograms of lunar samples. 

In honor of this historic launch, the National Air and Space Museum is projecting the identical rocket that took our astronauts to the Moon on the Washington Monument in Washington, D.C.

This week, you can watch us salute our Apollo 50th heroes and look forward to our next giant leap for future missions to the Moon and Mars. Tune in to a special two-hour live NASA Television broadcast at 1 p.m. ET on Friday, July 19. Watch the program at www.nasa.gov/live.

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#ITER DG Bernard Bigot opened #IBF2019 this morning, urging ITER’s industrial partners to continue to deliver their contributions on time and at the highest level of quality. #WeAreITER https://t.co/VVAVlnkFlR

The scaffolding has come off the lower cylinder of the #ITER #cryostat. Clad in thin film it is now being scanned by metrologists for reverse engineering and will then be cocooned for storage until assembly. #fusionenergy #WeAreITER https://t.co/DOag9p1rPp https://t.co/xoi5GTq0Vc

How Do We Learn About a Planet’s Atmosphere?

The first confirmation of a planet orbiting a star outside our solar system happened in 1995. We now know that these worlds – also known as exoplanets – are abundant. So far, we’ve confirmed more than 4000. Even though these planets are far, far away, we can still study them using ground-based and space-based telescopes.

Our upcoming James Webb Space Telescope will study the atmospheres of the worlds in our solar system and those of exoplanets far beyond. Could any of these places support life? What Webb finds out about the chemical elements in these exoplanet atmospheres might help us learn the answer.

How do we know what’s in the atmosphere of an exoplanet?

Most known exoplanets have been discovered because they partially block the light of their suns. This celestial photo-bombing is called a transit.

During a transit, some of the star’s light travels through the planet’s atmosphere and gets absorbed.

The light that survives carries information about the planet across light-years of space, where it reaches our telescopes.

(However, the planet is VERY small relative to the star, and VERY far away, so it is still very difficult to detect, which is why we need a BIG telescope to be sure to capture this tiny bit of light.)

So how do we use a telescope to read light?

Stars emit light at many wavelengths. Like a prism making a rainbow, we can separate light into its separate wavelengths. This is called a spectrum. Learn more about how telescopes break down light here. 

Visible light appears to our eyes as the colors of the rainbow, but beyond visible light there are many wavelengths we cannot see.

Now back to the transiting planet…

As light is traveling through the planet’s atmosphere, some wavelengths get absorbed.

Which wavelengths get absorbed depends on which molecules are in the planet’s atmosphere. For example, carbon monoxide molecules will capture different wavelengths than water vapor molecules.

So, when we look at that planet in front of the star, some of the wavelengths of the starlight will be missing, depending on which molecules are in the atmosphere of the planet.

Learning about the atmospheres of other worlds is how we identify those that could potentially support life…

…bringing us another step closer to answering one of humanity’s oldest questions: Are we alone?

Watch the full video where this method of hunting for distant planets is explained:

To learn more about NASA’s James Webb Space Telescope, visit the website, or follow the mission on Facebook, Twitter and Instagram. 

Text and graphics credit Space Telescope Science Institute

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For its first-of-a-kind tools #ITER demands creativity and innovation from industry, with impact on spin-off technologies and markets going well beyond plasma physics. #ITER's head of comms, @LabanCoblentz in @OpenAccessGov. https://t.co/MubR6Sowlt #WeAreITER https://t.co/JoXyVRtvQM

An unwrapped port cell door. Its size? It's massive - over 4 m wide, almost 4 m high, 80 cm deep and 60 tonnes heavy. 46 of these nuclear confinement doors will sit at the far end of openings around the #tokamak. https://t.co/uZcVBic4l9 #fusionenergy #WeAreITER https://t.co/lFsznJEsMP

The #ITER Domestic Agencies were also present at #IBF19. Here we are at the stand of Japan where you could also pick up a copy of the ITER mangas. @iterjapan #WeAreITER https://t.co/WBWbiA5ePK

Talking #ITER business in Russian and French at the exhibition stand of the Russian Domestic Agency. Russia contributes to many ITER components including the vacuum vessel, divertors, magnets and many more #IBF19 #WeAreITER https://t.co/PxHiA8G4uk

TESS’s first-year of planet-hunting was out of this world

Have you ever looked up at the night sky and wondered … what other kinds of planets are out there? Our Transiting Exoplanet Survey Satellite (TESS) just spent its first year bringing us a step closer to exploring the planets around the nearest and brightest stars in the southern sky and is now doing the same in the north.

TESS has been looking for dips in the brightness of stars that could be a sign of something we call “transits.” A transit happens when a planet passes between its star and us. It’s like when a bug flies in front of a light bulb. You may not notice the tiny drop in brightness when the bug blocks some of the light from reaching your eyes, but a sensitive camera could. The cameras on TESS are designed to detect those tiny drops in starlight caused by a transiting planet many light-years away.

In the last year TESS has found 24 planets and more than 900 new candidate planets. And TESS is only halfway through its goal of mapping over three-fourths of our skies, which means there’s plenty more to discover!

TESS has been looking for planets around the closest, brightest stars because they will be the best planets to explore more thoroughly with future missions. We can even see a few of these stars with our own eyes, which means we’ve been looking at these planets for millions of years and didn’t even know it.

We spent thousands of years staring at our closest neighbor, the Moon, and asking questions: What is it like? Could we live there? What is it made of (perhaps cheese?). Of course, now we can travel to the Moon and explore it ourselves (turns out, not made of cheese).

But for the worlds TESS is discovering, the commute to answer those questions would be killer. It took 35 years for Voyager 1 to cross into interstellar space (the region between stars), and it’s zipping along at over 38,000 mph! At that rate it would take more than a half-a-million years to reach the nearest stars and planets that TESS is discovering.

While exploring these distant worlds in person isn’t an option, we have other ways of learning what they are like. TESS can tell us where a planet is, its size and its overall temperature, but observatories on the ground and in space like our upcoming James Webb Space Telescope will be able to learn even more — like whether or not a planet has an atmosphere and what it’s made of.

Here are a few of the worlds that our planet hunter discovered in the last year.

Earth-Sized Planet

The first Earth-sized planet discovered by TESS is about 90% the size of our home planet and orbits a star 53 light-years away. The planet is called HD 21749 c (what a mouthful!) and is actually the second planet TESS has discovered orbiting that star, which you can see in the southern constellation Reticulum.

The planet may be Earth-sized, but it would not be a pleasant place to live. It’s very close to its star and could have a surface temperature of 800 degrees Fahrenheit, which would be like sitting inside a commercial pizza oven.

Water World?

The other planet discovered in that star system, HD 21749 b, is about three times Earth’s size and orbits the star every 36 days. It has the longest orbit of any planet within 100 light-years of our solar system detected with TESS so far.

The planet is denser than Neptune, but isn’t made of rock. Scientists think it might be a water planet or have a totally new type of atmosphere. But because the planet isn’t ideal for follow-up study, for now we can only theorize what the planet is actually like. Could it be made of pudding? Maybe … but probably not.

Magma World

One of the first planets TESS discovered, called LHS 3844 b, is roughly Earth’s size, but is so close to its star that it orbits in just 11 hours. For reference, Mercury, which is more than two and a half times closer to the Sun than we are, completes an orbit in just under three months.

Because the planet is so close to its star, the day side of the planet might get so hot that pools and oceans of magma form on its rocky surface, which would make for a rather unpleasant day at the beach.    

TESS’s Smallest Planet

The smallest planet TESS has discovered, called L 98-59 b, is between the size of Earth and Mars and orbits its star in a little over two days. Its star also hosts two other TESS-discovered worlds.

Because the planet lies so close to its star, it gets 22 times the radiation we get here on Earth. Yikes! It is also not located in its star’s habitable zone, which means there probably isn’t any liquid water on the surface. Those two factors make it an unlikely place to find life, but scientists believe it will be a good candidate for follow-up studies by other telescopes.

Other Data

While TESS’s team is hunting for planets around close, bright stars, it’s also collecting information on all sorts of other things. From transits around dimmer, farther stars to other objects in our solar system and events outside our galaxy, data from TESS can help astronomers learn a lot more about the universe. Comets and black holes and supernovae, oh my!

Interested in joining the hunt? TESS’s data are released online, so citizen scientists around the world can help us discover new worlds and better understand our universe.

Stay tuned for TESS’s next year of science as it monitors the stars that more than 6.5 billion of us in the northern hemisphere see every night.

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