Astronaut Journal Entry - Launch & Docking

... and we’re ‘GO’ for launch! 🚀

NASA Flight Integration Chief and past Mission Control Flight Director, Ginger Kerrick, is here answering your questions during this Tumblr Answer Time. Tune in and join the fun!

A Total Solar Eclipse Over South America

On Dec. 14, 2020, a total solar eclipse will pass over Chile and Argentina.

Solar eclipses happen when the Moon lines up just right between the Sun and Earth, allowing it to cast its shadow on Earth’s surface. People within the outer part of the Moon’s shadow will see the Sun partially blocked by the Moon, and those in the inner part of the shadow will see a total solar eclipse.

The Moon’s orbit around Earth is slightly tilted, meaning this alignment doesn’t happen on every orbit. Total solar eclipses happen somewhere on Earth about once every 18 months.

During a total solar eclipse, the Moon blocks out the Sun’s bright face, revealing its comparatively faint outer atmosphere, the corona. This provides Sun-watchers and scientists alike with a rare chance to see the solar corona closer to the Sun’s surface than is usually possible.

Scientists can take advantage of this unparalleled view — and solar eclipses’ unique effects on Earth’s atmosphere — to perform unique scientific studies on the Sun and its effects on Earth. Several NASA-funded science teams performed such studies during the total solar eclipse in the United States on Aug. 21, 2017. Read about what they’ve learned so far.

Watching the eclipse

We’ll be carrying images of December’s eclipse — courtesy of Pontificia Universidad Católica de Chile — on NASA TV and on the agency’s website starting at 9:40 a.m. EST on Dec. 14.

We’ll also have a live show in Spanish from 10:30 – 11:30 a.m. EST featuring views of the eclipse and NASA scientists.

If you’re observing the eclipse in person, remember that it’s never safe to look directly at the uneclipsed or partially eclipsed Sun. You can use special solar viewing glasses (NOT sunglasses) or an indirect method like pinhole projection to watch the eclipse in person.

For people in the path of totality, there will be a few brief moments when it is safe to look directly at the eclipse. Only once the Moon has completely covered the Sun and there is no sunlight shining is it safe to look at the eclipse. Make sure you put your eclipse glasses back on or return to indirect viewing before the first flash of sunlight appears around the Moon’s edge.

Mira el eclipse en vivo comentado por científicas de la NASA de 10:30 a 11:30 a.m. EST el 14 de diciembre en NASA TV y la página web de la agencia. Lee más sobre el eclipse y cómo observarlo de forma segura aquí: https://ciencia.nasa.gov/eclipse-de-2020-en-america-del-sur Y sigue a NASA en español en Instagram, Twitter, YouTube y Facebook.

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The Lives, Times, and Deaths of Stars

Who among us doesn’t covertly read tabloid headlines when we pass them by? But if you’re really looking for a dramatic story, you might want to redirect your attention from Hollywood’s stars to the real thing. From birth to death, these burning spheres of gas experience some of the most extreme conditions our cosmos has to offer.

All stars are born in clouds of dust and gas like the Pillars of Creation in the Eagle Nebula pictured below. In these stellar nurseries, clumps of gas form, pulling in more and more mass as time passes. As they grow, these clumps start to spin and heat up. Once they get heavy and hot enough (like, 27 million degrees Fahrenheit or 15 million degrees Celsius), nuclear fusion starts in their cores. This process occurs when protons, the nuclei of hydrogen atoms, squish together to form helium nuclei. This releases a lot of energy, which heats the star and pushes against the force of its gravity. A star is born.

Credit: NASA, ESA and the Hubble Heritage Team (STScI/AURA)

From then on, stars’ life cycles depend on how much mass they have. Scientists typically divide them into two broad categories: low-mass and high-mass stars. (Technically, there’s an intermediate-mass category, but we’ll stick with these two to keep it straightforward!)

Low-mass stars

A low-mass star has a mass eight times the Sun's or less and can burn steadily for billions of years. As it reaches the end of its life, its core runs out of hydrogen to convert into helium. Because the energy produced by fusion is the only force fighting gravity’s tendency to pull matter together, the core starts to collapse. But squeezing the core also increases its temperature and pressure, so much so that its helium starts to fuse into carbon, which also releases energy. The core rebounds a little, but the star’s atmosphere expands a lot, eventually turning into a red giant star and destroying any nearby planets. (Don’t worry, though, this is several billion years away for our Sun!)

Red giants become unstable and begin pulsating, periodically inflating and ejecting some of their atmospheres. Eventually, all of the star’s outer layers blow away, creating an expanding cloud of dust and gas misleadingly called a planetary nebula. (There are no planets involved.)

Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)

All that’s left of the star is its core, now called a white dwarf, a roughly Earth-sized stellar cinder that gradually cools over billions of years. If you could scoop up a teaspoon of its material, it would weigh more than a pickup truck. (Scientists recently found a potential planet closely orbiting a white dwarf. It somehow managed to survive the star’s chaotic, destructive history!)

High-mass stars

A high-mass star has a mass eight times the Sun’s or more and may only live for millions of years. (Rigel, a blue supergiant in the constellation Orion, pictured below, is 18 times the Sun’s mass.)

Credit: Rogelio Bernal Andreo

A high-mass star starts out doing the same things as a low-mass star, but it doesn’t stop at fusing helium into carbon. When the core runs out of helium, it shrinks, heats up, and starts converting its carbon into neon, which releases energy. Later, the core fuses the neon it produced into oxygen. Then, as the neon runs out, the core converts oxygen into silicon. Finally, this silicon fuses into iron. These processes produce energy that keeps the core from collapsing, but each new fuel buys it less and less time. By the point silicon fuses into iron, the star runs out of fuel in a matter of days. The next step would be fusing iron into some heavier element, but doing requires energy instead of releasing it.  

The star’s iron core collapses until forces between the nuclei push the brakes, and then it rebounds back to its original size. This change creates a shock wave that travels through the star’s outer layers. The result is a huge explosion called a supernova.

What’s left behind depends on the star’s initial mass. Remember, a high-mass star is anything with a mass more than eight times the Sun’s — which is a huge range! A star on the lower end of this spectrum leaves behind a city-size, superdense neutron star. (Some of these weird objects can spin faster than blender blades and have powerful magnetic fields. A teaspoon of their material would weigh as much as a mountain.)

At even higher masses, the star’s core turns into a black hole, one of the most bizarre cosmic objects out there. Black holes have such strong gravity that light can’t escape them. If you tried to get a teaspoon of material to weigh, you wouldn’t get it back once it crossed the event horizon — unless it could travel faster than the speed of light, and we don’t know of anything that can! (We’re a long way from visiting a black hole, but if you ever find yourself near one, there are some important safety considerations you should keep in mind.)

The explosion also leaves behind a cloud of debris called a supernova remnant. These and planetary nebulae from low-mass stars are the sources of many of the elements we find on Earth. Their dust and gas will one day become a part of other stars, starting the whole process over again.

That’s a very brief summary of the lives, times, and deaths of stars. (Remember, there’s that whole intermediate-mass category we glossed over!) To keep up with the most recent stellar news, follow NASA Universe on Twitter and Facebook.

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Pumpkin space latte, anyone? ☕

Hubble captured this festive array of stars, Terzan 12, found in the Milky Way about 15,000 light-years from Earth. The stars in this cluster are bound together by gravity in a sphere-like shape and are shrouded in gas and dust. As the starlight travels through that gas and dust to Earth, blue light scatters, leaving the redder wavelengths to come through.

Download the full-resolution image here.

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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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Mars Helicopter: 6 Things to Know About Ingenuity

When our Perseverance Mars rover lands on the Red Planet on Feb. 18, 2021, it will bring along the Ingenuity helicopter.

This small-but-mighty craft is a technology demonstration that will attempt the first powered, controlled flight on another planet. Its fuselage is about the size of a tissue box, and it weighs about 4 pounds (1.8 kg) on Earth. It started out six years ago as an implausible prospect and has now passed its Earthbound tests.

Here are six things to know about Ingenuity as it nears Mars:

1. Ingenuity is an experimental flight test.

This Mars helicopter is known as a technology demonstration, which is a project that aims to test a new capability for the first time with a limited scope. Previous technology demonstrations include Sojourner, the first Mars rover, and the Mars Cube One (MarCO) CubeStats that flew by Mars.

Ingenuity does not carry any science instruments and is not part of Perseverance’s science mission. The only objective for this helicopter is an engineering one – to demonstrate rotorcraft flight in the thin and challenging Martian atmosphere.

2. Mars won’t make it easy for Ingenuity.

Mars’ atmosphere is around 1% the density of Earth’s. Because of that lack of density, Ingenuity has rotor blades that are much larger and spin faster than a helicopter of Ingenuity’s mass here on our planet. It also must be extremely light to travel to Mars.

The Red Planet also has incredibly cold temperatures, with nights reaching minus 130 degrees Fahrenheit (-90 degrees Celsius) in Jezero Crater, where our rover and helicopter will land. Tests on Earth at the predicted temperatures indicate Ingenuity’s parts should work as designed, but the real test will be on Mars.

3. Ingenuity relies on Perseverance for safe passage to Mars and operations on the Martian surface.

Ingenuity is nestled sideways under Perseverance’s belly with a cover to protect the helicopter from debris during landing. The power system on the Mars 2020 spacecraft periodically charges Ingenuity’s batteries during the journey to the Red Planet.

In the first few months after landing, Perseverance will find a safe place for Ingenuity. Our rover will shed the landing cover, rotate the helicopter so its legs face the ground and gently drop it on the Martian surface.

4. Ingenuity is smart for a small robot.

NASA’s Jet Propulsion Laboratory will not be able to control the helicopter with a joystick due to delays communicating with spacecraft across interplanetary distances. That means Ingenuity will make some of its own decisions based on parameters set by its engineering team on Earth.

During flight, Ingenuity will analyze sensor data and images of the terrain to ensure it stays on a flight path designed by project engineers.

5. The Ingenuity team counts success one step at a time.

Ingenuity’s team has a long list of milestones the helicopter must pass before it can take off and land in the Martian atmosphere.

Surviving the journey to and landing on Mars

Safely deploying onto the Martian surface from Perseverance’s belly

Autonomously keeping warm through those intensely cold Martian nights

Autonomously charging itself with its solar panel

Successfully communicating to and from the helicopter via the Mars Helicopter Base Station on Perseverance

6. If Ingenuity succeeds, future Mars exploration could include an ambitious aerial dimension.

The Mars helicopter intends to demonstrate technologies and first-of-its-kind operations needed for flying on Mars. If successful, these technologies and flight experience on another planet could pave the way for other advanced robotic flying vehicles.

Possible uses of a future helicopter on Mars include:

A unique viewpoint not provided by current orbiters, rovers or landers

High-definition images and reconnaissance for robots or humans

Access to terrain that is difficult for rovers to reach

Could even carry light but vital payloads from one site to another

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Throwback Thursday: Apollo 11 FAQ Edition

With the help of the NASA History Office, we’ve identified some of the most frequently asked questions surrounding the first time humans walked on the surface of another world. Read on and click here to check out our previous Apollo FAQs. 

How many moon rocks did the Apollo crews bring back? What did we learn?

The six crews that landed on the Moon brought back 842 pounds (382 kilograms) of rocks, sand and dust from the lunar surface. Each time, they were transferred to Johnson Space Center’s Lunar Receiving Laboratory, a building that also housed the astronauts during their three weeks of quarantine. Today the building now houses other science divisions, but the lunar samples are preserved in the Lunar Sample Receiving Laboratory.

Built in 1979, the laboratory is the chief repository of the Apollo samples.

From these pieces of the Moon we learned that its chemical makeup is similar to that of Earth’s, with some differences. Studying the samples has yielded clues to the origins of the solar system. In March of 2019, we announced that three cases of pristine Moon samples will be unsealed for the first time in 50 years so that we can take advantage of the improved technology that exists today! 

Did you know you might not have to travel far to see a piece of the Moon up close? Visit our Find a Moon Rock page to find out where you can visit a piece of the Moon.

What did Apollo astronauts eat on their way to the Moon?

Astronaut food has come a long way since the days of Project Mercury, our first human spaceflight program that ran from 1958-1963. Back then, astronauts “enjoyed” food in cube form or squeezed out of tubes. Early astronaut food menus were designed less for flavor and more for nutritional value, but that eventually shifted as technology evolved. Astronauts today can enjoy whole foods like apples, pizza and even tacos. 

Apollo crews were the first to have hot water, making it easier to rehydrate their foods and improve its taste. They were also the first to use a “spoon bowl,” a plastic container that was somewhat like eating out of a Ziploc bag with a spoon. Here’s an example of a day’s menu for a voyage to the Moon:

Breakfast: bacon squares, strawberry cubes and an orange drink.

Lunch: beef and potatoes, applesauce and a brownie.

Dinner: salmon salad, chicken and rice, sugar cookie cubes and a pineapple grapefruit drink.

What did Michael Collins do while he orbited the Moon, alone in the Command Module?

As Neil Armstrong and Buzz Aldrin worked on the lunar surface, Command Module pilot Michael Collins orbited the Moon, alone, for the next 21.5 hours. On board he ran systems checks, made surface observations and communicated with Mission Control when there wasn’t a communications blackout. Blackouts happened every time Collins went behind the Moon. In 2009, Collins wrote this in response to a flurry of media questions about the 40th anniversary of the mission:

Q. Circling the lonely Moon by yourself, the loneliest person in the universe, weren't you lonely? A. No. Far from feeling lonely or abandoned, I feel very much a part of what is taking place on the lunar surface. I know that I would be a liar or a fool if I said that I have the best of the three Apollo 11 seats, but I can say with truth and equanimity that I am perfectly satisfied with the one I have. This venture has been structured for three men, and I consider my third to be as necessary as either of the other two.”

What will Artemis astronauts bring back when they land on the Moon?

Artemis missions to the Moon will mark humanity’s first permanent presence on another world. The first woman and the next man to explore the lunar surface will land where nobody has ever attempted to land before -- on the Moon’s south pole where there are billions of tons of water ice that can be used for oxygen and fuel. We don’t know yet what astronauts will bring back from this unexplored territory, but we do know that they will return with hope and inspiration for the next generation of explorers: the Artemis generation. Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.

Water, Water Everywhere; We Track Drops to Drink!

When we think about what makes a planet habitable, we’re often talking about water. With abundant water in liquid, gas (vapor) and solid (ice) form, Earth is a highly unusual planet. Almost 70% of our home planet’s surface is covered in water!

But about 97% of Earth’s water is salty – only a tiny amount is freshwater: the stuff humans, pets and plants need to survive.

Water on our planet is constantly moving, and not just geographically. Water shifts phases from ice to water to vapor and back, moving through the planet’s soils and skies as it goes.

That’s where our satellites come in.

Look at the Midwestern U.S. this spring, for example. Torrential rain oversaturated the soil and overflowed rivers, which caused severe flooding, seen by Landsat.

Our satellites also tracked a years-long drought in California. Between 2013 and 2014, much of the state turned brown, without visible green.  

It’s not just rain. Where and when snow falls – and melts – is changing, too. The snow that falls and accumulates on the ground is called snowpack, which eventually melts and feeds rivers used for drinking water and crop irrigation. When the snow doesn’t fall, or melts too early, communities go without water and crops don’t get watered at the right time.

Even when water is available, it can become contaminated by blooms of phytoplankton, like cyanobacteria . Also known as blue-green algae, these organisms can make humans sick if they drink the water. Satellites can help track algae from space, looking for the brightly colored blooms against blue water.

Zooming even farther back, Earth’s blue water is visible from thousands of miles away. The water around us makes our planet habitable and makes our planet shine blue among the darkness of space.

Knowing where the water is, and where it’s going, helps people make better decisions about how to manage it. Earth’s climate is changing rapidly, and freshwater is moving as a result. Some places are getting drier and some are getting much, much wetter. By predicting droughts and floods and tracking blooms of algae, our view of freshwater around the globe helps people manage their water.

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i cannot wait for my first solar eclipse! what's your favorite part about these eclipses, alexa?

I’ve never seen totality as the last time it was in the US was before I was born. My favourite part of seeing videos and photos is definitely viewing the solar corona! But I’m looking forward to this one so that I can see sunspots during the partial eclipse! It’s these spots that are often the active regions on the Sun that produce solar storms that can ultimately drive the aurora here on Earth! 

What’s it like launching into space?