Jovian Close Encounter

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.

How Big is Our Galaxy, the Milky Way?

When we talk about the enormity of the cosmos, it’s easy to toss out big numbers – but far harder to wrap our minds around just how large, how far and how numerous celestial bodies like exoplanets – planets beyond our solar system – really are.

So. How big is our Milky Way Galaxy?

We use light-time to measure the vast distances of space.

It’s the distance that light travels in a specific period of time. Also: LIGHT IS FAST, nothing travels faster than light.

How far can light travel in one second? 186,000 miles. It might look even faster in metric: 300,000 kilometers in one second. See? FAST.

How far can light travel in one minute? 11,160,000 miles. We’re moving now! Light could go around the Earth a bit more than 448 times in one minute.

Speaking of Earth, how long does it take light from the Sun to reach our planet? 8.3 minutes. (It takes 43.2 minutes for sunlight to reach Jupiter, about 484 million miles away.) Light is fast, but the distances are VAST.

In an hour, light can travel 671 million miles. We’re still light-years from the nearest exoplanet, by the way. Proxima Centauri b is 4.2 light-years away. So… how far is a light-year? 5.8 TRILLION MILES.

A trip at light speed to the very edge of our solar system – the farthest reaches of the Oort Cloud, a collection of dormant comets way, WAY out there – would take about 1.87 years.

Our galaxy contains 100 to 400 billion stars and is about 100,000 light-years across!

One of the most distant exoplanets known to us in the Milky Way is Kepler-443b. Traveling at light speed, it would take 3,000 years to get there. Or 28 billion years, going 60 mph. So, you know, far.

SPACE IS BIG.

Read more here: go.nasa.gov/2FTyhgH

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We Like Big Rockets and We Cannot Lie: Saturn V vs. SLS

On this day 50 years ago, human beings embarked on a journey to set foot on another world for the very first time. 

At 9:32 a.m. EDT, millions watched as Apollo astronauts Neil Armstrong, Buzz Aldrin and Michael Collins lifted off from Launch Pad 39A at the Kennedy Space Center in Cape Canaveral, Florida, flying high on the most powerful rocket ever built: the mighty Saturn V.

As we prepare to return humans to the lunar surface with our Artemis program, we’re planning to make history again with a similarly unprecedented rocket, the Space Launch System (SLS). The SLS will be our first exploration-class vehicle since the Saturn V took American astronauts to the Moon a decade ago. With its superior lift capability, the SLS will expand our reach into the solar system, allowing astronauts aboard our Orion spacecraft to explore multiple, deep-space destinations including near-Earth asteroids, the Moon and ultimately Mars.

So, how does the Saturn V measure up half a century later? Let’s take a look.

Mission Profiles: From Apollo to Artemis 

Saturn V

Every human who has ever stepped foot on the Moon made it there on a Saturn V rocket. The Saturn rockets were the driving force behind our Apollo program that was designed to land humans on the Moon and return them safely back to Earth.

Developed at our Marshall Space Flight Center in the 1960s, the Saturn V rocket (V for the Roman numeral “5”)  launched for the first time uncrewed during the Apollo 4 mission on November 9, 1967. One year later, it lifted off for its first crewed mission during Apollo 8. On this mission, astronauts orbited the Moon but did not land. Then, on July 16, 1969, the Apollo 11 mission was the first Saturn V flight to land astronauts on the Moon. In total, this powerful rocket completed 13 successful missions, landing humans on the lunar surface six times before lifting off for the last time in 1973.

Space Launch System (SLS) 

Just as the Saturn V was the rocket of the Apollo generation, the Space Launch System will be the driving force behind a new era of spaceflight: the Artemis generation.

During our Artemis missions, SLS will take humanity farther than ever before. It is the vehicle that will return our astronauts to the Moon by 2024, transporting the first woman and the next man to a destination never before explored – the lunar South Pole. Over time, the rocket will evolve into increasingly more powerful configurations to provide the foundation for human exploration beyond Earth’s orbit to deep space destinations, including Mars.

SLS will take flight for the first time during Artemis 1 where it will travel 280,000 miles from Earth – farther into deep space than any spacecraft built for humans has ever ventured.

Size: From Big to BIGGER 

Saturn V

The Saturn V was big. 

In fact, the Vehicle Assembly Building at Kennedy Space Center is one of the largest buildings in the world by volume and was built specifically for assembling the massive rocket. At a height of 363 feet, the Saturn V rocket was about the size of a 36-story building and 60 feet taller than the Statue of Liberty!

Space Launch System (SLS)

Measured at just 41 feet shy of the Saturn V, the initial SLS rocket will stand at a height of 322 feet. Because this rocket will evolve into heavier lift capacities to facilitate crew and cargo missions beyond Earth’s orbit, its size will evolve as well. When the SLS reaches its maximum lift capability, it will stand at a height of 384 feet, making it the tallest rocket in the world.

Power: Turning Up the Heat 

Saturn V

For the 1960s, the Saturn V rocket was a beast – to say the least.

Fully fueled for liftoff, the Saturn V weighed 6.2 million pounds and generated 7.6 million pounds of thrust at launch. That is more power than 85 Hoover Dams! This thrust came from five F-1 engines that made up the rocket’s first stage. With this lift capability, the Saturn V had the ability to send 130 tons (about 10 school buses) into low-Earth orbit and about 50 tons (about 4 school buses) to the Moon.

Space Launch System (SLS)

Photo of SLS rocket booster test

Unlike the Saturn V, our SLS rocket will evolve over time into increasingly more powerful versions of itself to accommodate missions to the Moon and then beyond to Mars.

The first SLS vehicle, called Block 1, will weigh 5.75 million pounds and produce 8.8 million pounds of thrust at time of launch. That’s 15 percent more than the Saturn V produced during liftoff! It will also send more than 26 tons  beyond the Moon. Powered by a pair of five-segment boosters and four RS-25 engines, the rocket will reach the period of greatest atmospheric force within 90 seconds!

Following Block 1, the SLS will evolve five more times to reach its final stage, Block 2 Cargo. At this stage, the rocket will provide 11.9 million pounds of thrust and will be the workhorse vehicle for sending cargo to the Moon, Mars and other deep space destinations. SLS Block 2 will be designed to lift more than 45 tons to deep space. With its unprecedented power and capabilities, SLS is the only rocket that can send our Orion spacecraft, astronauts and large cargo to the Moon on a single mission.

Build: How the Rockets Stack Up

Saturn V

The Saturn V was designed as a multi-stage system rocket, with three core stages. When one system ran out of fuel, it separated from the spacecraft and the next stage took over. The first stage, which was the most powerful, lifted the rocket off of Earth’s surface to an altitude of 68 kilometers (42 miles). This took only 2 minutes and 47 seconds! The first stage separated, allowing the second stage to fire and carry the rest of the stack almost into orbit. The third stage placed the Apollo spacecraft and service module into Earth orbit and pushed it toward the Moon. After the first two stages separated, they fell into the ocean for recovery. The third stage either stayed in space or crashed into the Moon.

Space Launch System (SLS)

Much like the Saturn V, our Space Launch System is also a multi-stage rocket. Its three stages (the solid rocket boosters, core stage and upper stage) will each take turns thrusting the spacecraft on its trajectory and separating after each individual stage has exhausted its fuel. In later, more powerful versions of the SLS, the third stage will carry both the Orion crew module and a deep space habitat module.

A New Era of Space Exploration 

Just as the Saturn V and Apollo era signified a new age of exploration and technological advancements, the Space Launch System and Artemis missions will bring the United States into a new age of space travel and scientific discovery.

Join us in celebrating the 50th anniversary of the Apollo 11 Moon landing and hear about our future plans to go forward to the Moon and on to Mars by tuning 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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First look at the 2024 total solar eclipse

The path of the April 8, 2024 total solar eclipse begins in the United States in Texas and ends in Maine. Google, INEGI

…The length of totality varies from one eclipse to the next. The reason is that Earth is not always the same distance from the Sun, and the Moon is not always the same distance from Earth. The Earth-Sun distance varies by 3 percent and the Moon-Earth distance by 12 percent. The result is that the maximum duration of totality from 2000 b.c. to a.d. 3000 is 7 minutes, 29 seconds. (That eclipse will occur July 16, 2186, so don’t get too excited for it.)

While the maximum length of totality during the April 8, 2024, eclipse won’t be that long, it’s still a worthy chunk of time: 4 minutes, 28 seconds — 67 percent longer than the one in 2017. And as with that one, everyone in the contiguous U.S. will see at least a partial eclipse. In fact, as long as you have clear skies on eclipse day, the Moon will cover at least 16.15 percent of the Sun’s brilliant surface. That minimum comes at Tatoosh Island, a tiny speck of land west of Neah Bay, Washington. And although our satellite covering any part of the Sun’s disk sounds cool, you need to aim higher.

Read more ~ Astronomy Magazine Posted by Michael Bakich on Sunday, September 23, 2018

Stellar Winds

Stellar winds are fast moving flows of material (protons, electrons and atoms of heavier metals) that are ejected from stars. These winds are characterised by a continuous outflow of material moving at speeds anywhere between 20 and 2,000 km/s.

In the case of the Sun, the wind ‘blows’ at a speed of 200 to 300 km/s from quiet regions, and 700 km/s from coronal holes and active regions.

The causes, ejection rates and speeds of stellar winds vary with the mass of the star. In relatively cool, low-mass stars such as the Sun, the wind is caused by the extremely high temperature (millions of degrees Kelvin) of the corona.

his high temperature is thought to be the result of interactions between magnetic fields at the star’s surface, and gives the coronal gas sufficient energy to escape the gravitational attraction of the star as a wind. Stars of this type eject only a tiny fraction of their mass per year as a stellar wind (for example, only 1 part in 1014 of the Sun’s mass is ejected in this way each year), but this still represents losses of millions of tonnes of material each second. Even over their entire lifetime, stars like our Sun lose only a tiny fraction of 1% of their mass through stellar winds.

In contrast, hot, massive stars can produce stellar winds a billion times stronger than those of low-mass stars. Over their short lifetimes, they can eject many solar masses (perhaps up to 50% of their initial mass) of material in the form of 2,000 km/sec winds.

These stellar winds are driven directly by the radiation pressure from photons escaping the star. In some cases, high-mass stars can eject virtually all of their outer envelopes in winds. The result is a Wolf-Rayet star.

Stellar winds play an important part in the chemical evolution of the Universe, as they carry dust and metals back into the interstellar medium where they will be incorporated into the next generation of stars. 

source (read more) + Wolf–Rayet star

Hurricanes Have No Place to Hide, Thanks to Better Satellite Forecasts

If you’ve ever looked at a hurricane forecast, you’re probably familiar with “cones of uncertainty,” the funnel-shaped maps showing a hurricane’s predicted path. Thirty years ago, a hurricane forecast five days before it made landfall might have a cone of uncertainty covering most of the East Coast. The result? A great deal of uncertainty about who should evacuate, where it was safe to go, and where to station emergency responders and their equipment.

Over the years, hurricane forecasters have succeeded in shrinking the cone of uncertainty for hurricane tracks, with the help of data from satellites. Polar-orbiting satellites, which fly nearly directly above the North and South Poles, are especially important in helping cut down on forecast error.

The orbiting electronic eyeballs key to these improvements: the Joint Polar Satellite System (JPSS) fleet. A collaborative effort between NOAA and NASA, the satellites circle Earth, taking crucial measurements that inform the global, regional and specialized forecast models that have been so critical to hurricane track forecasts.

The forecast successes keep rolling in. From Hurricanes Harvey, Irma and Maria in 2017 through Hurricanes Florence and Michael in 2018, improved forecasts helped manage coastlines, which translated into countless lives and property saved. In September 2018, with the help of this data, forecasters knew a week ahead of time where and when Hurricane Florence would hit. Early warnings were precise enough that emergency planners could order evacuations in time — with minimal road clogging.  The evacuations that did not have to take place, where residents remained safe from the hurricane’s fury, were equally valuable.

The satellite benefits come even after the storms make landfall. Using satellite data, scientists and forecasters monitor flooding and even power outages. Satellite imagery helped track power outages in Puerto Rico after Hurricane Maria and in the Key West area after Hurricane Irma, which gave relief workers information about where the power grid was restored – and which regions still lacked electricity. 

Flood maps showed the huge extent of flooding from Hurricane Harvey and were used for weeks after the storm to monitor changes and speed up recovery decisions and the deployment of aid and relief teams.

As the 2019 Atlantic hurricane season kicks off, the JPSS satellites, NOAA-20 and Suomi-NPP, are ready to track hurricanes and tropical cyclones as they form, intensify and travel across the ocean – our eyes in the sky for severe storms. 

For more about JPSS, follow @JPSSProgram on Twitter and facebook.com/JPSS.Program, or @NOAASatellites on Twitter and facebook.com/NOAASatellites.

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This Is What We Know About Black Holes In Advance Of The Event Horizon Telescope’s First Image

“For hundreds of years, humanity has expected black holes to exist. Over the course of all of our lifetimes, we’ve collected an entire suite of evidence that points not only to their existence, but to a fantastic agreement between their expected theoretical properties and what we’ve observed. But perhaps the most important prediction of all — that of the event horizon’s existence and properties — has never been directly tested before.

With simultaneous observations in hand from hundreds of telescopes across the globe, scientists have finished reconstructing an image, based on real data, of the largest black hole as seen from Earth: the 4 million solar mass monster at the center of the Milky Way. What we’ll see on April 10 will either further confirm General Relativity or cause us to rethink all that we believe about gravity. Eager with anticipation, the world now awaits.”

The Event Horizon Telescope will, on April 10 (tomorrow, at the time of this writing), release an image two years in the making: of the event horizon of the black hole at the Milky Way’s center. Many will look at this as the first definitive proof that black holes truly exist, but we mustn’t forget all the (overwhelming!) evidence we already have in hand. There is a ton that we already know about black holes that has been demonstrated observationally, and all of it is in spectacular agreement with what we theoretically expect.

On the eve of the Event Horizon Telescope’s big announcement, take some time to get a little perspective, and learn what we already know about black holes!

WHO IS HE?

In Genesis, He is the seed of the woman. In Exodus, He is the Passover Lamb. In Leviticus, He is our High Priest. In Numbers, He is pillar of cloud by day and a pillar of fire by night. In Deuteronomy, He is the prophet like unto Moses. In Joshua, He is the captain of our salvation. In Judges, He is our judge and lawgiver. In Ruth, He is our kinsman redeemer. In I and II Samuel, He is our trusted prophet. In Kings and Chronicles, He is our reigning king. In Erza, He is our faithful scribe. In Nehemiah, He is the rebuilder of the broken down walls of human life. In Ester, He is our Mordecai. In Job, He is our ever-living redeemer: “For I know my redeemer lives.” In Psalms, He is our shepherd. In Proverbs and Ecclesiastes, He is our wisdom. In Song of Solomon, He is the lover and the bridegroom. In Isaiah, He is the prince of peace. In Jeremiah, He is the righteous branch. In Lamentations, He is the weeping prophet. In Ezekiel, He is the wonderful four-faced man. In Daniel, He is the fourth man walking in the midst of the burning fiery furnaces of life. In Hosea, He is the husband forever married to the backslider. In Joel, He is the mighty baptizer in the Holy Ghost. In Amos, He is my burden bearer. In Obadiah, He is mighty to save. In Jonah, He is God’s great foreign missionary. In Micah, He is the messenger of beautiful feet. In Nahum, He is the avenger of God’s elect. In Habakkuk, He is God’s evangelist, crying, “Revive thy work in the midst of the years.” In Zephaniah, He is our Savior. In Haggai, He is the restorer of the lost heritage of Israel. In Zechariah, He is fountain opened up on the house of David for sin and uncleanness. In Malachi, He is the Son of Righteousness arisen with healing in His wings. In Matthew, He is the Messiah. In Mark, He is the wonder worker. In Luke, He is the Son of Man. In John, He is the Son of God. In Acts, He is the mighty baptizer in the Holy Ghost. In Romans, He is my justifier. In Corinthians, He is my sanctifier. In Galatians, He is the redeemer from the curse of the law. In Ephesians, He is the Christ of unsearchable riches. In Philippians, He is the God that supplies all my needs. In Colossians, He is the fullness of the godhead bodily. In I and II Thessalonians, He is my soon-coming King! In I and II Timothy, He is the mediator between God and man. In Tidus, He is my faithful pastor. In Philemon, He is the friend that sticketh closer than a brother. In Hebrews, He is the blood of the everlasting covenant. In James, He is our Great Physician, for “the prayer of faith shall save the sick.” In I and II Peter, He is my good shepherd. In I John, He is love. In II John, He is love.   In III John, He is love. In Jude, He is the Lord coming with 10,000 of His saints. In Revelation, He is King of Kings and Lord of Lords.

HE IS THE WORD OF GOD.

Yes, The Apollo Moon Landings Really Did Happen

“2.) We have extensive photographic and video evidence from the Apollo missions themselves. How could the lunar module have ascended back off of the surface and returned the astronauts back to the orbiting module which would take them back to Earth? Exactly like the video above shows, from direct Apollo 17 footage. The hypergolic propellant system isn’t based off of a single explosion, but rather a constant thrust of ~16,000 Newtons that was steadily delivered over a timespan of about 5 minutes. There’s no exhaust trail because there’s no lunar atmosphere, but you can track the spacecraft’s accelerated motion for yourself with even basic modern software.”

We’re less than a month away from the official 50th anniversary of the first crewed Moon landing, and there are all sorts of good reasons to celebrate. But for most of us alive today, the final Apollo mission occurred before we were born. Perhaps because of this distance between then and now, there are a great many people who don’t believe that the lunar landings ever occurred. While you might (rightfully) dismiss this position as an uninformed conspiracy, you can also immediately point to a slew of scientific evidence to demonstrate that yes, we did go to the Moon, and here is an enormous suite of data to back that up. From thousands of photographs to suites of instruments and scientific data to an examination of the landing sites today, everything lines up.

Come get the evidence for yourself, and don’t let someone’s conspiracy-minded ravings lead you astray.