13 Minutes to the Moon: 8. ‘We’re go for powered descent’

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In the last seven episodes, we've dug into the stories of the people, technology, and events that made Apollo 11's final 13 minutes of descent possible.

But in the next two, we want to pull all of that together.

We want to take you through the first landing on the moon from beginning to end, and through the moments where it teetered on the edge of failure or worse.

1202, staying by 1202.

Lost data flight.

Roger Copy.

I think we better be quiet.

Roger.

Okay, the only call-outs from now on will be fuel.

Low level?

Good.

1023.

The final 13 minutes were a leap into the unknown.

Nobody was confident the landing would succeed.

Apollo computer programmer Don Iles.

We were far from certain that we were going to end up with a successful landing.

We were pretty certain we were going to end up with a, you know, a live crew.

But trying this for the first time, I think we certainly had some apprehension about whether it was going to come out successfully.

In Houston's mission control, flight controllers like Jay Green shared these doubts.

We were doing something that had never been done before.

And we anticipated aborting.

Nobody on the team believed that we'd make it down the first time.

I don't think anybody did.

Yeah, it was intense.

Neil Armstrong knew what they were all up against.

It was far and away the most complex part of the flight.

The systems were very heavily loaded at that time.

The unknowns were rampant.

The systems in this mode had only been tested on Earth and never in the real environment.

There were just a thousand things to worry about in the final descent.

It was the thing that I worried about just because it was so difficult.

We choose to go to the moon.

Captain, we're go for landing.

Eagle Gibson, you're a go for landing over plus two feet.

Roger, low level, 60, 60 seconds.

We've had you down.

We're cutting you down, Eagle.

Tranquility Base here, the Eagle has landed.

I'm Kevin Fong, and from the BBC World Service, this is thirteen minutes to the moon.

Episode 8.

We're Go for Powered Descent.

We join the action in the final hour before the Apollo 11 landing.

At this point, both spacecraft are behind the Moon, out of radio contact with the Earth.

Michael Collins in the command module Columbia is in a 60-mile high orbit, whilst Neil Armstrong and Buzz Aldrin in Eagle are heading heading downwards on a gently sloping path.

But it won't be long before both craft emerge over the lunar horizon and contact is re-established.

In mission control, the tension is mounting for Flight Director Gene Krantz and his team of flight controllers.

The adrenaline, I mean, just really was, no matter how you tried to hide it, the fact is, is that you were really starting to pump.

And it seems that every controller has a common set of characteristics, is they've got to go to the bathroom.

I mean, it's just to the point where you just need this break.

That's all there is to it.

It's literally a rush to get to the bathroom.

And

you're standing in line.

And for a change, there isn't the normal banter.

No jokes, etc.

I mean, the level of preoccupation

in these people.

And these are kids.

These are the average age of my team was 26 years old.

And this preoccupation all of a sudden hits you.

This is different.

Then

you walk back into the room

and you hear the voice of the mission commentator, Doug Ward.

And he's commenting that the mission control team has returned from their break and they're now going to be in the room through the lunar landing.

And immediately that triggers my thought

that this team this day

is either going to land abort or crash those are the only three alternatives

this is apollo control at 102 hours 12 minutes into the flight of apollo 11

we're now two minutes 53 seconds from reacquiring the spacecraft

21 minutes 23 seconds from the beginning of the powered descent to the lunar surface.

It's grown quite quiet here in Mission Control.

A few moments ago, Flight Director Gene Kranz

requested that everyone sit down,

get prepared for events that are coming, and he closed with the remark, good luck to all of you.

A quarter of a million miles away, space-suited Neil Armstrong and Buzz Aldrin are racing towards the lunar horizon at a speed of about one mile a second.

They're getting ready to re-establish contact with mission control and preparing Eagle systems for the final descent.

They sound relaxed, remarking on the eerie whistling noise they can hear in their headsets.

Like wind whipping through the trees, says Armstrong.

But it's now time for the crew to perform a critical task, to prime the spacecraft for the final 13 minutes to the moon.

Aldrin instructs Eagle's guidance computer to start running Program P63.

which will control the precise moment at which the descent engine must ignite and how long it will burn for.

MIT's Don Iles wrote the lines of code for that essential program.

The landing program, P-63, had been selected.

It actually computed the exact ignition time and the attitude the spacecraft needed to be in at ignition.

Then there would have been a maneuver to the burn attitude, a program which Peter Adler and I had written called Burn Baby.

That was in operation at that time.

And in fact, on the Diski, which is the display and keyboard unit, the astronauts would have seen a dwindling number of seconds counting down to the ignition.

To many, these elegant programs are like works of art in their own right.

And that's certainly the case for space artist and Apollo historian Paul Fjell.

Program 63 basically calculates exactly when to start the engine based on all the information that's been given to it.

Where am I, how fast am I going.

Once once I know that and I know my final target, this position of the landing site, it uses this very clever algorithm that the computer can handle every two seconds to figure out when to fire the engine and then when it's firing the engine, how much of that trajectory have I eaten into and where do I need to point my engine to keep going along this nice trajectory?

Back in mission control, they're seconds away from AOS, acquisition of signal, the moment when Collins command module and Armstrong and Aldrin's Lem are due to reappear over the lunar horizon.

Remember Guidance Officer Steve Bales from episode 2.

The 26 year old is shortly to face the toughest decision of his life but here 50 years on he remembers the brief calm before the storm.

We have acquisition of signal.

Actually we hear the command module first because they're at a higher altitude.

They report things seem to be going well.

Columbia, Houston, over.

Capcom, Charlie Duke, calls out to Mike Collins.

Okay, he's coming along.

We copy out

AOS Lem

Roger AOS Lem.

We got acquisition of the spacecraft.

And from the time that the spacecraft cracks the hill until the time we're in the surface, it's about a half hour long.

It's about 18 minutes to look at the spacecraft and the telemetry, and then about 12 minutes from there to the surface of the moon from the time that we start the powered descent.

And immediately, as soon as we acquire telemetry, we're in trouble.

Because spacecraft spacecraft communications are absolutely lousy.

We can't communicate to them.

They can't communicate to us.

Hear the most noise and

data comes in and out and in and out.

And it is noisy as all get out.

And

Gene's got to decide we've got enough data to keep going on because his job, one of his jobs, is to decide are we in a position to monitor this vehicle and figure out what to do.

The problem here is with Eagle's most critical communication system, the high-gain antenna, a steerable aerial that can be pointed towards the Earth.

Without this radio link, Mission Control can't speak to Armstrong and Aldrin or receive data from the Lunar Module systems.

And without that telemetry, they can't land on the Moon.

All of this puts Gene Kranz under enormous pressure.

NASA management had to have some kind of a ground rule on how much

communications and telemetry we must have in order to allow the mission to continue.

And Kraft and I had lobbied for a very open loop.

The flight director will make this decision, where a lot of people wanted very precise.

We have to have it, you know, at the time of these events.

And what they were concerned about, sort of like a crash record in an airplane, if we crashed,

we wanted to know why we crashed.

Okay, so this is now we craft and I won, and we had this very loose mission rule.

And this is the only one that really bothers me because it's a pure judgment call.

This is the unique call of the flight director.

We have to call Mike Collins in the command module to relay data down into the lunar module.

And immediately this mission role is coming to mind because it's decision time, going to go time.

And

it just continues broken through about the first five minutes after we've acquired the data, but we get enough data.

So the controllers can make their calls, their decisions.

Are we good?

Are we properly configured?

Are we basically at the point in the procedures where we should be?

We move closer now to

what we call the powered descent go-no-go.

And this is where it's now time to say, are we going down the lunar surface or not?

Now I have one wave-off opportunity, and just only one.

And if I wave off in this powered descent, then I have one shot in the next rev and then the lunar mission's all over.

So you don't squander your

go-no-goes when you only got one more shot at it.

Come right up to the time of the go-no-go and we lose all data again.

Desperate for a solution to their communication problems, the team in Mission Control decide to try and turn Eagle to a new attitude, changing its orientation, giving the antenna a better line of sight to the earth in a bid to improve the signal.

Here, Charlie Chuke and Gene Krantz urgently troubleshoot the problem with telecommunications officer Don Putty.

Capcom, Charlie Juke.

The comm guys, they had us reorient Eagle several times to get better communications.

So we had to maneuver to get that.

10 degrees right, Florida.

I think.

I want them to roll about 10 degrees right.

Okay.

Eagle I use roller and we recognize

10 right will help us on the high gain signal strength over.

So I delay the gonna go with the team for roughly about 40 seconds.

To get data back briefly,

and I make the decision to press on it.

We're going to go in this one here.

So I have my controllers, okay, make their go-no-go's on the last valid data set that they had.

I know it's stale, but the fact is, is that it's not time to wave off.

Okay, off-flight controllers, go-no-go for powered descent.

Retro, go, FIDO, go, guidance, go, control, go, telecom, go.

GNC, go, e-comm, go, surgeon, go, Capcom, or go for powered descent.

And we give them the go for powered descent.

And immediately as soon as we go, we can't even give it to the crew directly.

We've got to voice this through Mike Collins down to the spacecraft.

As you can hear in these overlapping transmissions, the telecommunications team continue to battle with their antenna.

while Mission Control are forced to rely on Michael Collins in the command module to give Armstrong and Aldrin the all-important instruction that they're go to begin their powered descent.

Columbia, Houston, we lost him on the high gate again.

Could you please

we recommend ER right 10 degrees and reacquire

CDI and they recommend you are right 10 degrees and try the high gate again.

Got him and try the offers

again, sorry.

Dropped him in a moment.

Eagle E Columbia.

Okay.

All through this time, my mind is really running.

Is this enough data to keep going, going, going, going, going?

And this role, I'm going to be second guest, but that doesn't bother me.

Because I know whatever I'm going to do.

Despite the problems, Gene Krantz is going to proceed with the landing.

In Eagle's cabin, Armstrong and Aldrin watch their display counting towards zero, marking the time when they must fire their engine.

Okay, what else is left to do here?

Eagle is flying on its side with its legs and engine facing the direction of travel.

When the engine comes on and throttles up to maximum power, the mighty thrust is like slamming on the brakes.

As Eagle loses speed, it will drop rapidly from 50,000 feet towards the surface.

But before the final 13 minutes of descent can start, Buzz Aldrin has to arm arm the descent engine and hit the proceed button.

The flight controller talking to Gene Krantz in that clip is Bob Carlton, call sign control.

Bob's task is to monitor Eagle's descent engine, its attitude control jets, and its fuel.

Now, when when you start the engine, there's a short period of time when you burn it very low thrust and it settles under the, that creates artificial gravity in the fuel tanks.

And the fluid settles down against the bottom of the tank.

That's an ullage, we call that an ullage maneuver.

And then after you've had that settling effect, then you power the engine up and you begin to burn in earnest.

Start the engine.

Immediately have data problems again.

Guidance officer Steve Bales.

All kinds kinds of noise, lose the data, everything else.

I think it's for about a minute and no data.

And this is an incredibly important time to get

have our telemetry because as soon as we get acceleration, we settle our propellants in the tanks and now we can measure them.

But the problem is we miss this point.

So now we have to go with what we think are the quantities loaded pre-launch.

So we're in the process of continuing down.

We've now started down.

After a minute of broken communications, the signal finally becomes clear and data starts to flow to mission control once again.

But for Guidance Officer Steve Bales, the problems are only just starting.

I'm looking at my displays

and I am in big trouble because

that vehicle is going toward the moon 20 feet per second faster than it should be.

And I said, oh my gosh,

if it grows by another 15 feet per second, I got to abort.

Here's Steve conveying the message to Gene Kranz.

He doesn't use the word abort, but he knows his boss will understand the gravity of what he's saying.

Flight guns, okay, turn on we got 20 foot per second residual that is probably due to downtrack error.

I'll leave it alone.

About 20 foot residual due to downtrack error.

I think, and it was in radio.

Steve Bales says, flight, we're halfway to our abort limits.

I don't know what's caused it, but I'm going to keep watching it.

So all of a sudden, boom, we sure got my attention.

And that when you say you're halfway to your abort limits.

The lunar module appears to be traveling 20 feet per second faster than expected.

If this increases, it suggests that something is seriously wrong, possibly with Eagle's computer.

And if it reaches 35 feet per second, they'll have to abort the mission.

And Armstrong and Aldrin will be heading back for a risky rendezvous with Mike Collins 60 miles up.

So Steve watches the figure on his console like a hawk, hoping that it won't change.

It does not grow.

It does not grow.

How are you looking, guys?

Hanging out 20 foot per second.

Looks good.

Rog.

No change, is what you're saying.

No change.

And at some point, I said, we're going to make it, I think.

Okay, how about you guys?

Hold on to that 18 foot.

We're going to make it, I think.

Roger.

I've never said the word, I think.

I shouldn't even have said that, but I said, and we're going to make it, I think.

Three minutes into the powered descent, Neil Armstrong, from his vantage point in the lunar module, also notices that Eagle has been moving faster than expected.

We're wrong.

With the lamb on its side and his window facing the surface of the moon, he's been timing the the appearance of lunar landmarks, craters and mountains and comparing them to a checklist he'd prepared ahead of launch.

As to why Eagle is further along its flight path across the moon than planned, there are several possible explanations.

But Gene Krantz tracks the cause back to the moment when Eagle and Columbia undocked.

We didn't know this until after the mission, but the crew had not fully depressed the tunnel between the two spacecrafts.

They should have gone down to vacuum in there and they weren't.

So when they blew the bolts, when they released the latches between the spacecraft, there was a little residual air in there, which is sort of like popping a cork on a bottle.

It gave us velocity separating these two spacecrafts.

So now we're moving a little bit faster than we should have at this time.

So when the time came for Eagle to begin its power descent, this meant it had traveled much further further across the lunar surface than expected.

And this will have repercussions for the landing site.

Well,

even though this is looking now like it's going to be a go, it's going to cause a problem because it's going to move us down, instead of being at the landing point we had planned, we're now moving further downrange to the toe of our footprint, already know it's very rocky.

That rocky terrain will be the cause of great drama in the final two minutes before landing.

And we'll talk about about that in episode 9 but there's still plenty of hazard to overcome before we get there.

Guidance officer Steve Bales still needs final confirmation that the spacecraft's speed is going to stay within safe limits.

This will come from another instrument on the spacecraft.

So I'm sitting there praying for the landing radar because at some point the landing radar will come on.

and it will also know how fast you're going toward the moon.

The landing radar is on the opposite opposite side of the lunar module to its windows.

So Armstrong uses the thrusters to roll Eagle around by 180 degrees.

The crew are now looking out into the void of space and the radar is now pointing at the lunar surface about to lock on.

Okay, we got a good lock on.

We got a locker?

Yep, have a good light back, kid.

And

sure enough, at 35,000 or so feet, the landing radar comes on,

says, hey, you're going too fast.

At that point, I think my problems are over for the day.

That's my big problem.

In fact, Steve's really big problem is only 10 seconds away.

It's the next great possible abort moment in Apollo 11's landing.

the 1202 computer alarm crisis.

We told this story from mainly Steve's perspective in episode 2, but here let's take a deeper dive into why Eagle's computer cries out that it's dangerously overloaded not once but five times during Eagle's descent.

It starts with the landing radar locking onto the lunar surface.

It gives the crew and mission control their first real measurement of Eagle's altitude above the moon.

Up till then, they've been using an estimate based based on how high the computer senses it is according to its onboard instruments.

The difference between the altitude sensed by Apollo's guidance computer and that measured by the radar is called delta H.

The two should be in close agreement.

If they differ by more than a few thousand feet, the crew will have to abort.

So, that measurement of delta H is all important.

Here's the moment when the crew and Houston get their first reading.

Radar flight looks good.

Raj, 2,000 feet.

Raj, 2,000 feet.

Roger, we copy.

That's the Earth right out our front window.

Buzz can only enjoy the view of home for a moment.

Apollo coder, Don Iles, explains what happens next.

At that point, Buzz Aldrin keyed into the disci, the display and keyboard unit, verb 16, noun 68,

which brought up a display where he could see, in fact, the delta H, which he expected to see diminishing towards zero.

That extra load on the computer, caused by that entry into the keyboard,

pushed us into a state where there wasn't quite enough time for the computer to do everything

that was asked of it.

And the first of the alarms was a response to that condition.

An alarm buzzes like an angry hornet in the crew's headsets.

1202.

Very much.

1202.

On their display, they can see the numbers 1202.

And they don't know what it means.

The crew sees it four seconds before we do.

We're running about four seconds behind.

1202 alarm.

1202.

I'm frantically trying to remember what the blank is 12.02.

That was the shocker for me.

Capcom Charlie Duke.

When crew said 12.02 alarm, my mind was, that's it.

We're not going to land.

Just as shocked and fearing that the landing attempt might have to be abandoned is Don Isles, sitting at a loudspeaker, piping the mission audio into MIT.

It was extremely alarming because we didn't know what was happening.

It was totally unexpected.

So that's what made it scary.

There was something happening inside the computer that we did not understand

here early on in the landing maneuver.

If it had been up to me, I might have called an abort at that time.

Houston actually knew better than us because they had studied some of these so-called impossible alarms and had seen that, in fact, the limb could keep flying in the presence of this alarm.

So they had the courage and presence of mind to say, okay, press on.

As you may remember from episode two, just before the launch of Apollo 11, Gene Krantz had insisted that flight controller Steve Bales and his backroom support Jack Garmin itemize every single alarm that the computer might throw up.

Here's Jack Garmin talking about this some years later.

Gene Kranz, who is the real hero of that whole episode,

so he made us write down every, we made us go off and study every every single computer alarm that existed in the code and to figure out, even if we couldn't come up with a reason for why the alarm would happen,

what were the manifestations if it did?

I mean,

is it over?

Is the computer dead?

Is it something, you know, what would you do if it did happen, even if you don't know?

So we did.

We did.

I still have a copy of it.

It's handwritten

under a piece of plastic.

And we wrote it down for every single computer alone and stuck it under the glass on the console.

If we hadn't have done that, I don't know what would have happened.

I really honestly don't.

We might have gone on, we might have not, but boy was it helpful.

Here again is how the team handled the crisis five minutes into the final descent.

Jack, after about 10 seconds, I'm sure he's frantically looking at his notes.

I'm trying to find my, it's the last thing in the world I think we're going to have.

I'm looking, it's under my console glass, I'm trying to look for it, before I can even spot it, Jack says, Steve, Steve, it's one of those that if it doesn't happen too much, we'll go.

It's executive overflow.

If it does not occur again, we're fine.

I look up at my other displays.

We still know where we're at.

We've got the right altitude.

We know now how fast we're going toward dear moon, how fast we're going horizontally.

Greeting on the 1203 program alarm.

Is it flight, we're going out of line?

We're We're going that flight.

I heard him, I mean, it was a shout.

So I said, I immediately said, we're going that alarm.

Roger, we got you.

We're going that alarm.

Roger, he's taking it at our page now.

Roger.

Usually, the Capcom never says anything unless the flight director says do it.

But even before he got those words out, Charlie Duke, he was up on the airgo and said, you're going that alarm.

I mean, that was critical information for them.

And so I got that out as quick as I could.

So every time an alarm had come up, they were same type, but slightly different.

And we were always go on those alarms.

When Neil Armstrong calls out for the reading on that first program alarm, I am convinced you can hear the urgency in his voice.

Give up the reading on the 1202 program alarm.

But in this interview, recorded in 2001, Armstrong suggests the alarms weren't such a big deal.

You're always concerned when...

any kind of alarm comes on, but

it wasn't a serious concern because there there wasn't anything obviously wrong.

The vehicle was flying well, it was going down the trajectory we expected, no abnormalities in anything that we saw other than the computer said there's a problem and it's not my fault.

And the people here on the ground were right on top of that.

And

of course the computer continued in a contrary manner periodically all the way to the surface.

Armstrong was nothing if not inscrutable.

But as Don Isles told me, there was good reason to believe the astronaut was worried.

The program alarms were very definitely a distraction.

Armstrong says that in the, you know, the technical crew debriefing, that in fact he was preoccupied with whether the limb was going to keep flying.

I think after the first few, they became a little bit blasé about the alarms.

Even later on, when

as a result of the alarms, or I should say as a result of the condition that then led to the alarms, the disci even went blank.

But, you know, they were certainly in a very excited state.

You know, we know what Armstrong's heartbeat was, and even though he really wasn't doing much physical activity, it got up above 150 or so.

So

they were under a fair amount of stress.

I imagine our heart rates were elevated in Cambridge too, although we didn't have any sensors on us.

It's important to understand the 1202 alarms.

They didn't represent computer crashes in the conventional sense.

Instead, the Apollo computer was signaling that it had too much to do and had to prioritise only the mission-critical tasks like keeping Eagle flying at the right speed on the right trajectory.

This was a brilliant safety feature engineered by the programmers at MIT.

So Armstrong and Aldrin temporarily lose some of the computer's functions, but nothing that they can't manage without.

But why was the computer becoming overloaded?

BuzzAltrin would quickly diagnose the problem.

We rejoin the mission audio just after the program alarm sounds a second time.

Same alarm, and it appears to come up when we have a 1668 of.

Roger, copy.

Okay, we'll monitor stuff age flight.

Roger, I think that's what's good.

Okay, Eagle Houston wheel minor.

To talk us through this is David Mendel, professor of aeronautics and astronautics at MIT.

When Aldrin quickly realizes the program alarm, which keeps coming up and you know could threaten to destroy the mission, Aldrin says, it seems to come when we have a 1668, which is the verb noun command that brings up monitoring of this quantity, delta H.

crucial measure of the quality of the landing data.

He says, it seems to happen when we have delta H.

And the crew on the ground realize that as well, and they say, we'll monitor your delta H from here.

Okay, we'll monitor his delta H flight.

Rog.

I think that's what it's getting.

Okay, Eagle of Houston, we'll monitor your delta H.

It means that the crew in the LEM doesn't have to do that operation anymore.

They move both the cognitive load off the crew and the processing load off the computer across this 250,000-mile telemetry link down into Houston.

The crew down there then monitors that quantity.

It just unloads the computer enough to bring the load down below the critical level and allow them to continue with the landing.

Delta H is beautiful.

Delta H is looking good now.

Project Delta H is looking good to

do that.

This ability to share a complex taskload between people and machines and across the void of space is emblematic of how NASA operated during Project Apollo and a key reason for its success.

To me, that's the moment where this very complex, subtle, distributed human machine network gets this problem, diagnoses it, solves it, moves on, and gets on with the landing.

And it's really miraculous to watch this team go because we now start working these two incredibly complex problems simultaneously.

One part of the team is working this, the other part of the team is doing this, and I'm trying to put all the pieces together with Charlie Duke, who's picking the right fragments of conversation up to send up to the crew.

We're continuing to work our way down to the surface.

Now, fortunately, the communications have improved dramatically.

Communications are just a dream, okay?

And now

things are happening, and this team

is incredible.

Some person, the voice loop, comes up and says,

and everybody relaxes.

Here you're fighting problems that just unbelievable and you keep working your way to the surface, to the surface, to the surface.

Flying control broken, that's good.

Flight, Roger.

Go guys.

So now it's 68.

Now well may be the problem here and we can monitor delta H.

Roger.

Flight fight on look real good.

Rog fight oh good.

At seven minutes you're looking great to us Eagle.

Talk how you looking?

Look good, Floyd.

Rog, so we may tend to lose as we gradually take over.

Let me try auto again.

I'll see what.

The computer alarms are apparently under control.

And nine minutes since the engine began the powered descent, the computer starts to run a new program.

P63 gives way to P64.

P64.

Okay, they got sweet power.

This begins to pitch the spacecraft upright, preparing the crew for their final approach to the landing site.

As they pitch over and see the moon for the first time, Neil said, we can't land here.

There's a big area of rocks.

In episode 9, with 7,500 feet to go, Armstrong and Aldrin are headed to a site littered with massive boulders.

Evasive action is needed, but time and fuel are running out.

The tension in mission control was through the roof.

Eel had hold of the controls, skating across the landscape.

We'd never seen anybody flying it this way in training.

We were holding our breath.

60.

He's telling me we got 60 seconds of fuel.

30 seconds.

We got 30 seconds of fuel.

The good gun.

13 Minutes to the Moon is an original podcast from the BBC World Service.

Roger

13 Minutes to the Moon is produced by Andrew Luck Baker.

Our theme music is by Hans Zimmer.

Extra production and research effort is by Sue Norton and Madeleine Finley.

The series editor is Rami Zabar and the podcast editor is John Minnell.

Many thanks to NASA for archive material and especially big thanks to its Johnson Space Center oral history project for the interview clips with Neil Armstrong, Gene Krantz and Bob Carlton.

There's a lot more of them in episode 9.

If you want to dig deep into Apollo history, I recommend you visit the project's website.

There are transcripts of hundreds of interviews they've done with astronauts, mission control staff, engineers, and NASA managers over the years.

And thanks to you two for all of your comments on the podcast.

All the ratings and reviews are really very much appreciated.

On social media, our hashtag is 13 Minutes to the Moon.

That's all one word.

And if you haven't done it already, check out the Apollo videos, photos, and documents on our website.

That's at bbcworldservice.com slash 13 minutes.

I'm Kevin Fong.

Thanks for listening.

Wouldn't it be nice if your cash savings could just grow by itself?

With the Wealthfront Cash Account, it can, earning 4% annual percentage yield from partner banks on your uninvested cash, nearly 10 times the national average.

Just imagine if other things in your life worked the way Wealthfront works.

If your houseplants grew at 10 times the average rate, you'd have 10 times fewer issues with sad, stunted succulents.

Your crocodile ferns would go to the size of crocodiles.

Wealthfront's cash account keeps your money thriving just like that, earning you an industry-leading rate with no account maintenance fees and with free 24-7 instant withdrawals so you can access your money whenever you you need it.

Money works better here.

Go to wealthfront.com to start saving.

Cash account offered by Wealthfront Brokerage LLC member Fenra SIPC.

Wealthfront is not a bank.

The APY on cash deposits as of December 27, 2024, is representative, subject to change, and requires no minimum.

Funds in the cash account are swept to partner banks where they earn the variable APY.

The national average interest rate for savings accounts is posted on FDIC.gov as of December 16, 2024.

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