Why do rockets need so much fuel if, in space, there is nothing to slow them down once they are up to speed?

Robert Frost:

The propellant is primarily needed to get the spacecraft into orbit, not to stay in orbit.

In the above picture, you can see an illustration of a mission to the Moon. Rockets are conventionally built to have multiple stages. This is done because so much fuel is needed to get a payload from the surface to orbital altitude and accelerated to orbital speed. When about half the propellant is burned, the bottom half of the rocket is jettisoned. This makes the remaining rocket considerably lighter, which means when the engines in the next stage ignite, they will have a greater effect. The same can happen again when that next stage runs out of fuel. Eventually, all that’s left is the payload, traveling in the desired orbit. If that payload is carrying fuel, it is because it might have to do some other maneuver, such as a retro-fire to come home or a burn to transfer to another orbit, or it might need to control its attitude using small reaction control jets.

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Own a car long enough and you will eventually find yourself standing in an auto repair shop trying to decipher what the technician is trying to tell you. The only common language? How much it’s going to cost.

Even though you might not understand all the nuts and bolts of a repair job, it’s still important you have enough information to make an informed decision. We asked mechanic Charles Sanville of The Humble Mechanic blog to pass along five simple questions that should elicit some helpful information from a repairman before (and after) you commit to getting the work done.

1. “CAN YOU SHOW ME THE PROBLEM?”

Most mechanics are not out to rip you off. But if they are, they can often be tripped up by a simple request to see which part is in need of attention. “You always want to ask this,” Sanville says. “Tell them you want to see the part that’s failing.” While some issues might be with a car’s electronics and therefore won’t have a physical spot to point to, it’s still a good idea to try. Having a visual aid will also make a tech’s explanation easier to understand.

2. “WHAT HAPPENS IF I DON’T FIX THIS?”

Be sure to ask the shop what the consequences might be of not taking care of an issue right away. “You should ask what happens in the long term if something doesn’t get fixed,” Sanville says. While a timing belt might need replacement, it’s possible it might be good for another few thousand miles; a brake issue probably can’t wait.

3. “CAN YOU PRIORITIZE THESE REPAIRS?”

Some technicians make repairs seem like urgent matters, but not everything needs to be addressed immediately. “Having five issues isn’t uncommon, but a couple of them might not be a big deal and can wait,” Sanville says. “Have them prioritize what’s wrong with the car.”

4. “CAN I SEE THE DEFECTIVE PART?”

Before the repair has been made, request that the shop save the faulty part so you can take a look. “Sometimes they’ll let you keep it,” Sanville says, depending on disposal requirements. It’s tangible proof they did the work promised.

5. “CAN YOU EXPLAIN HOW YOU FIXED IT?”

Don’t worry about understanding much—or any—detail about the repair work. What you really want, Sanville says, is to build a relationship with the technician and not just the service advisor behind the counter. “Ask them to explain in a technical way what the problem was, how they caught it, and how it was fixed. It’ll help build a relationship and then you’ll have your own tech. You can bring it to ‘Bill’ instead of just ‘ABC Auto.’ That’s a guy who will know you and know your car and do what he can to keep you on the road.”

Some prayers might make reference to wine, but they certainly don’t talk about Hennessy. Or emptying clips. Or, well, pretty much anything else found in Tupac Shakur’s 1996 song “Hail Mary.” But that wasn’t enough to stop one church in Sri Lanka from accidentally distributing the lyrics to the rap song instead of the Catholic prayer of the same name, CNN reports.

The lyrics were included in a booklet of prayers for the church’s Christmas carol service in the capital city of Colombo on December 11 and were immediately identified (and tweeted) by several people attending. The book, by the way, advertised the event as “A Festival of Music for Peace & Harmony” so a line like “F— the world if they can’t adjust, it’s just as well, Hail Mary” is going to raise some eyebrows:

A Christmas Carol service in Sri Lanka has accidentally printed the lyrics of Tupac’s Hail Mary, instead of the prayer.#SriLanka #lka pic.twitter.com/djhJPAWhcj

— Ravindu Thimantha G. (@IamRavindu) December 25, 2016

Instead of opening the booklet to the familiar refrain of “Hail Mary, full of grace. The Lord is with thee,” devotees were greeted by words of wisdom from Tupac like, “Makaveli in this, Killuminati, all through your body. The blow’s like a twelve gauge shotty, feel me.”

“A lot of people were in shock as [to] whether it was a joke or someone would actually rap the song,” churchgoer Andrew Choksy told CNN. “A few of the older ladies in front of us could not stop looking at the printed booklet.”

The booklet was apparently prepared by a young boy, who had simply downloaded the wrong version of “Hail Mary” from the internet, somehow glossing over lines like “Come with me, Hail Mary/Run quick see, what do we have here/Now, do you wanna ride or die?”

The error was caught soon after the books were distributed, according to Father Da Silva, from the Archdiocese of Colombo. “The page was in the middle of the booklet. When people looked at this page, they saw it before the start of the show. Two people saw it and alerted us to it,” he told CNN.

[h/t: CNN]

From Krampus to Santa Claus, the holiday season is filled with all sorts of memorable characters. On December 26, 1973, the studio executives at Warner Bros. added a new kind of yuletide tot into the mix: Regan MacNeil, a demonic tween famous for her distaste for pea soup and unholy attitude toward religious relics. Here are 20 fascinating facts about William Friedkin’s groundbreaking horror film.

1. THE EXORCIST IS BASED ON A TRUE STORY.

William Peter Blatty’s novel is based on the real-life 1949 exorcism of a young boy, known by the pseudonym Roland Doe. The story became national news, and caught the interest of Blatty, who was a student at Georgetown University at the time (hence the change in location).

2. WILLIAM PETER BLATTY WROTE THE NOVEL IN A CABIN IN CALIFORNIA.

In Beyond Comprehension: William Peter Blatty’s The Exorcist, one of the new featurettes on the 40^th edition Blu-ray, Blatty returns to the scene of The Exorcist’s beginning: the cabin in the hills of Encino, California where he wrote the novel more than four decades ago.

3. THE NAME OF THE DEMON IS PAZUZU.

Though it’s never stated in the film, the demon that takes possession of Regan MacNeil has a name: Pazuzu, which is taken from the name of the king of the demons in Assyrian and Babylonian mythology. 

4. MERCEDES MCCAMBRIDGE PROVIDED THE VOICE OF THE DEMON.

The woman Orson Welles once dubbed “the world’s greatest living radio actress” was hired to provide the voice for Linda Blair’s most demonic moments, a decision that became the source of much controversy when McCambridge was not credited for her performance. Some say that this decision was solely McCambridge’s, who claimed that she didn’t want to take away from Blair’s performance, then later changed her mind. Under the threat of legal action, her name was quickly added to the credits.

5. MCCAMBRIDGE ADOPTED A VERY SPECIFIC DIET TO ACHIEVE THAT RASPINESS.

Sounding like a demon has its downsides. In the case of McCambridge, she believed that chain smoking and a diet of raw eggs and whiskey were the key to a great vocal performance.

6. PIG SQUEALS WERE A KEY PART OF THE SOUND DESIGN.

Much of Regan’s moaning and grunting were created by remixing pig squeals. When the demon is finally exorcised from her body, the sound you hear is a group of pigs being led to slaughter.

7. IT WAS THE FIRST HORROR FILM TO BE NOMINATED FOR A BEST PICTURE OSCAR.

The horror genre has never gotten much love from the Academy. Though there still seems to be a bias against scary movies during awards season, The Exorcist earned 10 Oscar nominations in 1974, including a Best Supporting Actress nod for Linda Blair, who was just 15 years old at the time. Unfortunately, the teenager’s nomination was met with much controversy as word about McCambridge’s contribution to the role spread. 

8. VIOLET BEAUREGARDE WAS CONSIDERED FOR THE ROLE OF REGAN.

Denise Nickerson, who most famously played Violet Beauregarde in Mel Stuart’s Willy Wonka & the Chocolate Factory, was in contention for the role of Regan. But then her parents got a hold of the script and, troubled by what they read, pulled her from the production’s shortlist.

9. LINDA BLAIR’S MOTHER LOVED THE SCRIPT.

Ironically, Linda Blair’s agents never even considered her for the role, though they did send the producers more than two dozen other young actresses to consider. It was Blair’s mother who brought her to the attention of the studio’s casting department and Friedkin.

10. BLATTY INSISTED THAT WILLIAM FRIEDKIN DIRECT THE FILM.

Blatty made a smart decision when he sold the rights to his novel, but stayed on as one of The Exorcist’s producers. That way, his opinion would have to matter. And while the studio had its own short list of directors to approach for the gig—Arthur Penn, Peter Bogdanovich, Mike Nichols, and Stanley Kubrick among them—Blatty only had eyes for Friedkin, believing that the film would benefit from a grittier style, similar to what Friedkin had done on The French Connection. When the studio told Blatty that they had hired Mark Rydell for the film, Blatty stood his ground—and won! 

11. MARLON BRANDO WAS THE STUDIO’S FIRST CHOICE FOR FATHER MERRIN.

It was Friedkin who vetoed this decision, believing that any movie starring Marlon Brando would immediately become a “Brando movie,” which would detract from the story at hand. The role eventually went to Max von Sydow.

12. MAX VON SYDOW WAS ONLY 44 AT THE TIME OF SHOOTING.

It took many hours in the chair with makeup artist Dick Smith to age the actor the 30 or so years the role required. Some have even joked that there are scenes in which von Sydow is wearing more makeup than the demonic Regan. Von Sydow’s three-hour daily aging process was achieved with a mix of stipple and liquid latex.

13. JASON MILLER WAS A LAST-MINUTE—ALBEIT INTENTIONAL—SUBSTITION.

There were a few big names being bandied about for the role of Father Karras, with Jack Nicholson in the early mix before Blatty settled on Stacy Keach. But then Friedkin happened to see a performance of That Championship Season, which was written by and starred Jason Miller. Friedkin knew they had found their man and, as he recounts in his new memoir, The Friedkin Connection (part of which is excerpted in the new 40^th edition Blu-ray from Warner Bros.), they purchased Keach out and in stepped Miller, in his feature acting debut.

14. THE MOVIE’S MOST FAMOUS IMAGE IS BASED ON A MAGRITTE PAINTING.

The Exorcist’s most iconic image—the one that would eventually serve as its poster and movie box art—is of the moment that Father Merrin arrives at the MacNeil residence and, illuminated by a street lamp, looks up at the home. This image was inspired by René Magritte’s 1954 painting, Empire of Light.

15. “THE EXORCIST STEPS” HAVE REMAINED A POPULAR TOURIST ATTRACTION.

At the end of M Street in Washington, D.C. is where you’ll find one of the film’s location landmarks: a set of stone stairs onto (and down) which Regan “throws” Father Karras from her window, which have come to be known as “The Exorcist Steps.” Rumor has it that on the day of filming the scene in which a stuntman rolled down the steps, Georgetown students who lived nearby rented out their rooftops to the tune of $5 per person so that interested onlookers could get a better view. 

16. THROWING ANYONE DOWN THOSE STAIRS FROM THE WINDOW WOULD BE IMPOSSIBLE.

Yes, even for a kid with demonic strength, because, in reality, Regan’s window was located about 40 feet from the top of the stairs. It was a bit of Hollywood magic-making—a.k.a. the addition of a wing built by the production’s set decorators—that made the trajectory of Karras’ untimely tumble seem possible. 

17. MANY OF THE CAST AND CREW MEMBERS BELIEVED THE SET WAS CURSED.

Filming in the U.S. took place in both New York City and Washington, D.C. After a number of eerie incidents on the New York City set, including a studio fire that forced the team to rebuild the sets of the house interiors, Blatty and Friedkin regularly brought in a priest, Father King, to bless the cast, crew, and set when production moved to D.C. By the end of the film’s production, nine people associated with its making had passed away.

18. REGAN PREFERS ANDERSEN’S PEA SOUP.

By now it is well known that the substance Regan projectile vomits onto Father Karras in one of the film’s most famous—and disgusting—scenes is pea soup. But more specifically, it’s Andersen’s pea soup, mixed with a little oatmeal. Campbell’s soup was tried, but the crew apparently didn’t like the effect as much. 

19. JASON MILLER’S REACTION TO BEING COVERED IN SAID PEA SOUP IS AUTHENTIC.

Friedkin was known for sometimes using manipulative tactics in order to elicit the most authentic reactions possible from his actors. Miller was told that the substance would hit him in the chest only; whether that was a lie or the equipment misfired is debated. But Miller’s disgusted reaction is absolutely real. Unsurprisingly, the scene only required one take. 

20. THE EXORCIST MADE A FEW AUDIENCE MEMBERS NAUSEOUS, TOO. 

So many, in fact, that some theaters began handing out The Exorcist barf bags with every ticket. 

Ten years after teaming up on 1983’s Scarface, Al Pacino and director Brian De Palma reunited for Carlito’s Way (1993), a tale about Carlito Brigante, a Puerto Rican ex-con who gets drawn back into illegal activities soon after getting out of prison, despite genuinely wanting to keep his nose clean. Penelope Ann Miller (playing Carlito’s girlfriend, Gail) and Sean Penn (the lawyer David Kleinfeld) co-starred in the film, delivering performances that earned them both Golden Globe nominations.

1. NEW YORK STATE SUPREME COURT JUDGE EDWIN TORRES MADE A LOT OF MONEY SELLING THE MOVIE RIGHTS TO HIS BOOK REPEATEDLY.

He sold the movie rights to his Carlito books 10 times before it was finally optioned. “When the producer told me they were going to finally make it, I told him I’m losing money here!” Torres said. “I just as soon kept selling the options.”

2. AL PACINO WAS ONE OF THE FIRST PEOPLE TO READ TORRES’S BOOKS.

”I showed him the books in galleys. It was just predestined (that Pacino would play Carlito),” Torres told Entertainment Weekly. The two used to work out together at the YMCA. Carlito’s Way, Torres’s first book to feature the titular character, came out in 1975, the year Pacino’s Dog Day Afternoon was released.

3. ONLY TORRES KNOWS WHO CARLITO IS PATTERNED AFTER.

Carlito Brigante is based on three people that Torres knew, but he could never reveal who they were because of their criminal histories. Torres also said that Kleinfeld was based on actual attorneys he had encountered over the years. “Three lawyers I knew personally have been murdered in situations not dissimilar to Kleinfeld’s.”

4. BRIAN DE PALMA WASN’T SURE HE WANTED TO MAKE ANOTHER GANGSTER MOVIE.

De Palma read the screenplay by David Koepp (Jurassic Park with Michael Crichton), even though he didn’t think he wanted to go back to a familiar genre. “I didn’t even want to read it. I didn’t want to return to this terrain again,” he said.

5. MARTIN SCORSESE PREVENTED IT FROM BEING CALLED AFTER HOURS.

Torres’s two Carlito Brigante books are titled Carlito’s Way and After Hours (1979). Despite the titles, the movie Carlito’s Way is actually based on After Hours. However, Scorsese came out with a black comedy titled After Hours in 1985, and De Palma wanted to avoid repeating the title. The prequel Carlito’s Way 2: Rise to Power (2005) was based on Torres’s first book.

6. JOHN LEGUIZAMO TURNED DE PALMA DOWN FOUR TIMES.

Leguizamo played the memorable (to most) Bronx native Benny Blanco only after De Palma let him create his own character. He told The A.V. Club that he turned the director down four times because he “just felt that it wasn’t enough of a part. Luckily, [Brian] De Palma and I had worked together on Casualties Of War (1989), so he let me improvise my ass off. I totally went off. I created this character, you know, all the bizarre back story, that he’s a go-getter who can’t wait to meet Pacino. I think that was the first time I really felt like I had found myself in movies. That was a great time… I’ll always love De Palma, because Carlito’s Way was where I found myself in film.”

7. PACINO AND PENELOPE ANN MILLER GOT VERY CLOSE.

When asked about the alleged romantic relationship she had with her co-star, Miller (Adventures in Babysitting [1987], Kindergarten Cop [1990]) shrugged and answered, “It’s not a secret and I’m not ashamed of it.” Miller added that the two tried to keep the relationship discreet “for the sake of the movie.”

8. SEAN PENN SAID “YES” TO CARLITO’S WAY SO THAT HE COULD DIRECT THE CROSSING GUARD.

Penn had written The Crossing Guard (1995) but had trouble getting studios to finance it. Then De Palma, his director on 1989’s Casualties of War, called him late one night. “I needed a chunk of change—because I had a kid now and bills to pay—and the part Brian was offering me in Carlito’s Way was a good one, plus it was with Al [Pacino], whom I love, so I did that. And then eventually I was able to set up The Crossing Guard.”

9. PENN AND DE PALMA DID NOT ALWAYS GET ALONG.

“He’s an operatic moviemaker, so the reality level is somewhere off in De Palma-ville, and to get hold of it is impossible,” Penn claimed in 1996. “How to serve him is hard to get a grasp on, so it can become confrontational. And it did, to a degree, on Carlito’s Way.” He also said that working with Pacino was something he loved. “Working with him balanced that whole experience out.”

“I remember when I was shooting Carlito’s Way,” De Palma said, after he was asked if any of his actors took things too far. “There’s this scene where Sean is all coked up, and he’s trying to get [Al Pacino] to go on the boat trip with him. Because of where the sun was, I was shooting Sean over Al’s back for the beginning. I shot ten, fifteen takes, and I thought it looked pretty good. But Sean said, ‘No, no, no, no, no.’ I said ‘What?!’ He said, ‘We don’t have it.’ I said, ‘I think we do.’ He said, ‘I need a few more takes.’ He said, ‘Twenty.’ I said, ‘Twenty?? Ok…’ I shot ten more, I think, and then I said, ‘Sean, I have to shoot this two-shot, then I gotta go over and shoot Al. He’s been playing to you all morning.’ But Sean was never happy with the scene. And I came around, and shot a two-shoot, and an over-the-shoulder.”

10. PENN DID NOT INTEND FOR HIS CHARACTER TO LOOK LIKE ALAN DERSHOWITZ.

Sean Penn’s perm in the film was inspired, the actor claimed, by a picture in Life magazine of a law student from the Carlito’s Way time period. “I tucked it into my script and went from there.”

Viewers, and some movie reviewers, noted that he resembled Dershowitz, who supposedly threatened litigation. In reality, Torres brought in John Gotti’s lawyer, Albert Krieger, to the set to talk to Penn about his earlier years on Gotti’s team.

11. A PLANNED WORLD TRADE CENTER SHOOTOUT HAD TO BE CHANGED AT THE LAST MINUTE.

“I had elaborate storyboards of this whole shootout on the escalators that were in the World Trade Center,” De Palma said. “I spent weeks and weeks photographing it … and a couple of days before we were about to shoot, they blew it up.” The epic shootout took place in Grand Central Station instead.

12. THE STUDIO WANTED TO MAKE IT SHORTER.

Universal Pictures asked De Palma if the movie could be cut down from its two hours, 25 minutes length, since a shorter time would ensure more showings in theaters. But De Palma knew a release date was already in place. De Palma told Universal, “Hey, guys, do you want me to have the movie open November 8th, or do you want me to figure out how to make twenty minutes out of it?” The release date obviously won out.

13. BENNY BLANCO MADE AN UNEXPECTED IMPACT.

After the movie opened, bags of heroin called “Benny Blanco” were dealt in New York City.