A Space Starburst

Throwback Thursday: Frequently Asked Questions about Apollo

In celebration of the 50th anniversary of Apollo 11, we’ll be sharing answers to some frequently asked questions about the first time humans voyaged to the Moon. Answers have been compiled from archivists in the NASA History Office.

How many people worked on the Apollo program?

At the height of Apollo in 1965, about 409,900 people worked on some aspect of the program, but that number doesn’t capture it all.

It doesn’t represent the people who worked on mission concepts or spacecraft design, such as the engineers who did the wind tunnel testing of the Apollo Command Module and then moved on to other projects. The number also doesn’t represent the NASA astronauts, mission controllers, remote communications personnel, etc. who would have transferred to the Apollo program only after the end of Gemini program (1966-1967). There were still others who worked on the program only part-time or served on temporary committees. In the image above are three technicians studying an Apollo 14 Moon rock in the Lunar Receiving Laboratory at Johnson Space Center. From left to right, they are Linda Tyler, Nancy Trent and Sandra Richards.

How many people have walked on the Moon so far?

This artwork portrait done by spaceflight historian Ed Hengeveld depicts the 12 people who have walked on the Moon so far. In all, 24 people have flown to the Moon and three of them, John Young, Jim Lovell and Gene Cernan, have made the journey twice.  

But these numbers will increase.

Are the U.S. flags that were planted on the Moon still standing?

Every successful Apollo lunar landing mission left a flag on the Moon but we don’t know yet whether all are still standing. Some flags were set up very close to the Lunar Module and were in the blast radius of its ascent engine, so it’s possible that some of them could have been knocked down. Neil Armstrong and Buzz Aldrin both reported that the flag had been knocked down following their ascent. 

Our Lunar Reconnaissance Orbiter took photographs of all the Apollo lunar landing sites. In the case of the Apollo 17 site, you can see the shadow of the upright flag.

But why does it look like it’s waving?

The flags appear to “wave” or “flap” but actually they’re swinging. Swinging motions on Earth are dampened due to gravity and air resistance, but on the Moon any swinging motion can continue for much longer. Once the flags settled (and were clear of the ascent stage exhaust), they remained still.  And how is the flag hanging? Before launching, workers on the ground had attached a horizontal rod to the top of each flag for support, allowing it to be visible in pictures and television broadcasts to the American public. Armstrong and Aldrin did not fully extend the rod once they were on the Moon, giving the flag a ripple effect. The other astronauts liked the ripple effect so much that they also did not completely extend the rod. 

Why don’t we see stars in any of the pictures?

Have you ever taken a photo of the night sky with your phone or camera? You likely won’t see any stars because your camera’s settings are likely set to short exposure time which only lets it quickly take in the light off the bright objects closest to you. It’s the same reason you generally don’t see stars in spacewalk pictures from the International Space Station. There’s no use for longer exposure times to get an image like this one of Bruce McCandless in 1984 as seen from Space Shuttle Challenger (STS-41B).

The Hasselblad cameras that Apollo astronauts flew with were almost always set to short exposure times. And why didn’t the astronauts photograph the stars? Well, they were busy exploring the Moon!

When are we going back to the Moon?

The first giant leap was only the beginning. Work is under way to send the first woman and the next man to the Moon in five years. As we prepare to launch the next era of exploration, the new Artemis program is the first step in humanity’s presence on the Moon and beyond.

Keep checking back for more answers to Apollo FAQs.

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Hi there! Does the study of Earth Science teach us much about the science of other planets? Can much be assumed to be similar, or is the geology/biology incomparable? Thank you!

Want to Send Your Art to the International Space Station?!

For children ages 4-12, we’re hosting an art contest! Get the details:

We are working with Boeing and SpaceX to build human spaceflight systems, like rockets and spacecraft, to take astronauts to the International Space Station. These companies will fly astronauts to orbit around Earth while we focus on plans to explore deeper into our solar system. 

Get out your art supplies and use your creative imagination to show us the present and future of traveling in space!

There are no grocery stores in space, but there may soon be farms. Very small farms that are important to a crew conducting a mission to deep space. That’s because our astronauts will need to grow some of their own food. Researchers on Earth and astronauts on the International Space Station are already showing what is needed to grow robust plants in orbit.

What would you take to space? Astronaut Suni Williams took a cutout of her dog, Gorbie, on her first mission to the International Space Station. 

Kids 4 to 12, draw what you would take and enter it in our Children’s Artwork Calendar contest! Your entry could be beamed to the space station!

Go to http://go.nasa.gov/2fvRLNf for more information about the competition’s themes, rules and deadlines plus the entry form. 

Get your parent's permission, of course!

Email your entry form and drawing to us at: ksc-connect2ccp@mail.nasa.gov

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How does flying feel?

55 Cancri e: Where Skies Sparkle Above a Never-ending Ocean of Lava

We’ve discovered thousands of exoplanets – planets beyond our solar system – so far. These worlds are mysterious, but observations from telescopes on the ground and in space help us understand what they might look like.

Take the planet 55 Cancri e, for instance. It’s relatively close, galactically speaking, at 41 light-years away. It’s a rocky planet, nearly two times bigger than Earth, that whips around its star every 18 hours (as opposed to the 365 days it takes our planet to orbit the Sun. Slacker).

The planet’s star, 55 Cancri, is slightly smaller than our Sun, but it’s 65 times closer than the Sun is to Earth. Imagine a massive sun on the horizon! Because 55 Cancri e is so close to its star, it’s tidally locked just like our Moon is to the Earth. One side is always bathed in daylight, the other is in perpetual darkness. It’s also hot. Really hot. So hot that silicate rocks would melt into a molten ocean of melted rock. IT’S COVERED IN AN OCEAN OF LAVA. So, it’s that hot (between 3,140 degrees and 2,420 degrees F).

Scientists think 55 Cancri e also may harbor a thick atmosphere that circulates heat from the dayside to the nightside. Silicate vapor in the atmosphere could condense into sparkling clouds on the cooler, darker nightside that would reflect the lava below. It’s also possible that it would rain sand on the nightside, but … sparkling skies!

Check out our Exoplanet Travel Bureau's latest 360-degree visualization of 55 Cancri e and download the travel poster at https://go.nasa.gov/2HOyfF3.

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What dose it feel like being inside a space suit?

The suit weighs about 300 pounds. We are made neutrally buoyant in the pool, but over time we can become negatively buoyant. The suit can feel heavy, even the bearings can become stiff, so it can be difficult to operate in the suit. With practice and the help of a great spacewalk team, we can make a spacewalk look seamless.

What exactly is a sun eclipse? Will I be able to see it and if so when from the Netherlands?

The solar eclipse is when the moon is directly in front of the Sun and creates a shadow on the Earth. They happen about once every 18 months. I don’t believe that you’ll be able to see this eclipse from the Netherlands. I think the next one to be in Europe is in 2026. There’s one in Chillie and Argentia in 2019 and another in Antartica in 2021. 

Eclipse 2017: A Unique Chance for Science

On Aug. 21, the Moon will cast its shadow down on Earth, giving all of North America the chance to see a solar eclipse. Within the narrow, 60- to 70-mile-wide band stretching from Oregon to South Carolina called the path of totality, the Moon will completely block out the Sun’s face; elsewhere in North America, the Moon will cover only a part of the star, leaving a crescent-shaped Sun visible in the sky.

Find eclipse times for your location with our interactive version of this map.

A total solar eclipse happens somewhere on Earth about once every 18 months. But because Earth’s surface is mostly ocean, most eclipses are visible over land for only a short time, if at all. The Aug. 21 total solar eclipse is different – its path stretches over land for nearly 90 minutes, giving scientists an unprecedented opportunity to make scientific measurements from the ground.

No matter where you are, it is never safe to look directly at the partially eclipsed or uneclipsed Sun. Make sure you’re prepared to watch safely, whether that’s with solar viewing glasses, a homemade pinhole projector, or online with us at nasa.gov/eclipselive.

Within the path of totality, the Moon will completely obscure the Sun’s face for up to 2 minutes and 40 seconds, depending on location. This will give people within the path of totality a glimpse of the innermost reaches of the Sun’s corona, the outer region of the atmosphere that is thought to house the processes that kick-start much of the space weather that can influence Earth, as well as heating the whole corona to extraordinarily high temperatures.

In fact, scientists got their first hint at these unusually high temperatures during the total solar eclipse of 1869, when instruments detected unexpected light emission. It was later discovered that this emission happens when iron is stripped of its electrons at extremely high temperatures.

This region of the Sun’s atmosphere can’t be measured at any other time, as human-made instruments that create artificial eclipses must block out much of the Sun’s atmosphere – as well as its bright face – in order to produce clear images.

We’re funding six science investigations to study the Sun’s processes on Aug. 21. Teams will spread out across the path of totality, focusing their instruments on the Sun’s atmosphere. One team will use a pair of retro-fitted WB-57F jets to chase the Moon’s shadow across the eastern US, extending the time of totality to more than 7 minutes combined, up from the 2 minutes and 40 seconds possible on the ground.

Our scientists are also using the Aug. 21 eclipse as a natural science experiment to study how Earth’s atmosphere reacts to the sudden loss of solar radiation within the Moon’s shadow.

One region of interest is Earth’s ionosphere. Stretching from roughly 50 to 400 miles above Earth’s surface, the tenuous ionosphere is an electrified layer of the atmosphere that reacts to changes from both Earth below and space above and can interfere with communication and navigation signals.

The ionosphere is created by ionizing radiation from the Sun. When totality hits on Aug. 21, we’ll know exactly how much solar radiation is blocked, the area of land it’s blocked over and for how long. Combined with measurements of the ionosphere during the eclipse, we’ll have information on both the solar input and corresponding ionosphere response, enabling us to study the mechanisms underlying ionospheric changes better than ever before.

The eclipse is also a chance for us to study Earth’s energy system, which is in a constant dance to maintain a balance between incoming radiation from the Sun and outgoing radiation from Earth to space, called the energy budget. Like a giant cloud, the Moon during the 2017 total solar eclipse will cast a large shadow across a swath of the United States.

Our scientists already know the dimensions and light-blocking properties of the Moon, and will use ground and space instruments to learn how this large shadow affects the amount of sunlight reaching Earth’s surface, especially around the edges of the shadow. This will help develop new calculations that improve our estimates of the amount of solar energy reaching the ground, and our understanding of one of the key players in regulating Earth’s energy system — clouds.

Learn all about the Aug. 21 eclipse at eclipse2017.nasa.gov, and follow @NASASun on Twitter and NASA Sun Science on Facebook for more. Watch the eclipse through the eyes of NASA at nasa.gov/eclipselive starting at 12 PM ET on Aug. 21.

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What’s Up for August 2017

The total solar eclipse on August 21 will trace a narrow path across the nation, although most of the U.S. will see a partial eclipse. Here's what to do before, during and after the eclipse, plus how you can become a citizen scientist helping us with eclipse observations.

Not everyone can travel to the path of totality, so here are some things you can do whether you see totality or a partial eclipse. 

Collecting Citizen Science

Want to be a citizen scientist? 

Before the eclipse, make and pack your very own eclipse toolkit, containing a notebook, pen, a clock, a stopwatch, the front page of a newspaper, a thermometer, and a stick with a piece of crepe paper tied to it. Don’t forget your assistant, who will help conduct science observations. 

Practice using a citizen scientist phone app, like our GLOBE app to study clouds, air and surface temperatures and other observations. Go to the location where you plan to observe the eclipse and check for any obstructions. You may want to focus on only one activity as the eclipse will last less than 3 minutes ... or just really experience the eclipse. 

Cell phones don’t take eclipse video! And plan to have your safe eclipse-viewing glasses within reach for before and after totality. Just before totality, if you have a good view of the horizon, look west to see the approaching shadow. After totality, look east low on the horizon for the departing shadow.

During totality, look for stars. You should be able to see the star Regulus in the solar corona or the stars of Orion.

During totality, we may see moving bands of shadows, like on the bottom of a swimming pool.

How dark does it get at totality? Look at the newspaper you brought with you. What is the smallest print you can read?

How much does the temperature drop? Does the wind stop or change direction?

Use your hands, a sheet of paper with a hole in it, a kitchen colander or any other object with one or more holes to use as a pinhole projector. You’ll be able to see the crescent shape of the sun projected through the holes.

Find out more about the eclipse, including eclipse safety, at https://eclipse2017.nasa.gov

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Introducing Astronaut Story Time – from Earth! 📖⁣⁣

Tomorrow and each weekday at 4 p.m. EDT, record-breaking astronaut Christina Koch, who recently returned to our home planet after 328 days in space, will read a children’s book on HER Instagram Live!⁣

👉🏽Follow @Astro_Christina to enjoy #NASAatHome ⁣ ⏰Tap our story on Instagram to set a reminder to tune in ⁣ ⁣ If you want to learn more about life as one of our @NASAastronauts or you want to apply to #BeAnAstronaut, click HERE. Applications close in 5 days. ⁣

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