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The Manhattan Project Bomb You Haven't Heard Of

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Wikimedia Commons

You probably know Little Boy and Fat Man as the atomic bombs detonated over Hiroshima and Nagasaki, effectively ending WWII. The U.S. rushed headlong into the development of the bombs, trying to actualize the atomic bomb ahead of the Nazis. And we did it.

But during the Manhattan Project scientists developed at least four bombs—Thin Man, The Gadget, Little Boy and Fat Man—three of which made it to fruition (The Gadget, Little Boy, and Fat Man) with two actually being used in war (Little Boy and Fat Man). Why haven’t you heard of Thin Man? Well, it never saw the light of day.

How to Build An Atomic Bomb

There are two different ways to build an atomic bomb. One is gun-type assembly, in which a hollow, sub-critical (less mass than needed to sustain a chain reaction) fissile “bullet” is shot at a solid supercritical (able to sustain a chain reaction) core. The bullet strikes and compresses the core, fission happens, and the bomb explodes. This type of assembly is relatively simple in design, involving one thing being shot at another, and we’d been building non-nuclear things of this sort for years before the Manhattan Project.

The second type of assembly is a bit more complex. Implosion-type assembly involves a hollow sphere containing a complex arrangement of high explosives and detonators, surrounding a solid fissile, but not yet supercritical core. The high explosives are detonated in such a way that the blast wave compresses the core to a supercritical density. This causes fission, which makes the bomb explode.

Thin Man was a gun-type weapon designed to use plutonium as fuel. But scientists found that the reactor-produced plutonium available at the time contained too many impurities, causing a greatly increased spontaneous fission rate, which basically means that the fuel would pre-detonate and blow itself apart while trying to attain criticality, rather than after, which was kind of putting the nuclear cart before the horse. So the bomb was scrapped, and focus turned to Little Boy.

Cue Uranium

Little Boy was the same type of weapon as Thin Man—except for the fact that it used uranium rather than plutonium. Since uranium isn’t as prone to pre-detonation, a much simpler weapon was designed, without many of the safeguards of the Thin Man design.

Even though plutonium wasn’t a good choice for gun-type weapons, it worked well in the implosion design, which included more safety features that prevented pre-detonation of the plutonium. While Thin Man and Little Boy were being developed, the scientists were also working on The Gadget and Fat Man, which were both implosion-type devices, using plutonium (and uranium) as fuel.

Since the implosion design was more complex, it was tested before being put into action. The Gadget was detonated in the New Mexico desert during the Trinity Test on July 16, 1945. The test was successful, and became the first man-made nuclear explosion in history, and we were now relatively certain that Fat Man would work as expected since it used the same design.

No Tests Necessary

We were so confident of our scientific prowess that we sent the pieces for Little Boy to the Mariana Islands for final assembly two hours before the Trinity Test. Now remember, this weapon design was completely different, and we had never done any of this before. So why didn’t we test the design for Little Boy?

Well, the gun-type assembly was thought to be simple enough that it would detonate without problem. And enriched uranium was much harder to come by than plutonium, so we didn’t want to waste the rare stuff on a test. Time was also a factor: It had taken years to enrich enough uranium to use in this one bomb, and the war was raging on. We simply didn’t want to wait the months or years necessary to accumulate enough uranium for another bomb.

Less than three weeks after the Trinity Test, Little Boy was successfully detonated over Hiroshima on August 6, 1945. Three days later, Fat Man was detonated over Nagasaki, adding atomic weapons to mankind’s arsenal for the first time.

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Civilian Researchers Discover Wreckage of the USS Indianapolis
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On July 30, 1945, the cruiser USS Indianapolis sank in the Pacific Ocean after it was torpedoed by the Imperial Japanese Navy submarine I-58. More than 70 years after the historic naval tragedy— which claimed the lives of nearly 900 crew—The New York Times reports that the ship’s mysterious final resting place has been found.

The discovery came courtesy of a team of civilian researchers, led by Microsoft co-founder Paul Allen. His state-of-the-art research vessel, Petrel, located the wreck 18,000 feet below the Pacific’s surface, the team announced on Saturday, August 19.

"To be able to honor the brave men of the USS Indianapolis and their families through the discovery of a ship that played such a significant role in ending World War II is truly humbling,” Allen said in a statement. “As Americans, we all owe a debt of gratitude to the crew for their courage, persistence, and sacrifice in the face of horrendous circumstances."

Before it sank, the USS Indianapolis had just completed a top-secret mission to a naval base on the Northern Mariana island of Tinian. After delivering enriched uranium and components for Little Boy— the atomic bomb that the U.S. would drop on the Japanese city of Hiroshima about a week later—the cruiser forged ahead to Guam, and then to the Philippines. It was supposed to meet the battleship USS Idaho at Leyte Gulf in the Philippines to prepare to attack Japan.

The USS Indianapolis never made it to Leyte Gulf. Shortly after midnight on July 30, the Japanese submarine I-58 spotted the cruiser and fired six torpedoes. The USS Indianapolis—which was hit twice—sank within 12 minutes. Around 300 to 400 sailors and Marines were killed in the attack; the rest were stranded in the Pacific Ocean for several days.

Many of these survivors would ultimately lose their lives to sharks, a grisly scene that would be famously (albeit semi-accurately) recounted in the 1975 movie Jaws. Others died from drowning, heat stroke, thirst, burns and injuries, swallowing salt water or fuel oil, and suicide. More than 300 crew members were rescued after a bomber pilot accidently sighted the imperiled men while on a routine antisubmarine patrol.

The mass tragedy—which wouldn’t be announced to the public until August 15, 1945—sparked controversy: Charles B. McVay III, captain of the USS Indianapolis, was found guilty in a court martial of failing to steer the ship on a “zigzag” course to elude Japanese submarines. A Japanese submarine captain testified that this precautionary measure wouldn’t have thwarted the enemy, but McVay was charged nonetheless. The captain died by suicide in 1968, and wouldn’t be officially exonerated by the Navy until 2001.

For decades, the remains of the USS Indianapolis were lost to the ravages of time and nature. But in 2016, naval historian Richard Hulver found a historic ship log that mentioned a sighting of the USS Indianapolis. Allen’s search team used this information to locate the ship, which was west of where experts assumed it had gone down.

Allen’s crew took pictures of the wreckage, including a piece of its hull, and will search for more of the ship. They plan to keep the exact location of the USS Indianapolis a secret, however, to honor the sunken ship as a war grave.

"While our search for the rest of the wreckage will continue, I hope everyone connected to this historic ship will feel some measure of closure at this discovery so long in coming,” Allen said.

[h/t The New York Times]

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The Time That Dean Martin and Jerry Lewis Opened Competing Restaurants on the Sunset Strip
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From 1946 to 1956, Dean Martin and Jerry Lewis were show business supernovas. With an act that combined singing, slapstick, and spontaneous hijinks, the duo sold out nightclubs coast to coast, then went on to conquer radio, television, and film. Long before Elvis and The Beatles came along, Dean and Jerry  were rock stars of comedy.

Offstage, there was a cordial but cool friendship between the laidback Martin and the more neurotic Lewis. But as the pressures of their success increased, so did the tensions between them. Martin grew tired of playing the bland romantic straight man to Lewis’s manic monkey boy. And when Lewis started to grab more headlines and write himself bigger parts in their movies, Martin decided to quit the act. In an angry moment, he told Lewis that he was “nothing to me but a f**king dollar sign.”

After the split, both men went on with their individual careers, though it took Martin a few years before he regained his footing. One of his ventures during that transitional period was a Hollywood eatery called Dino’s Lodge.


In the summer of 1958, Martin and his business partner, Maury Samuels, bought a controlling interest in a restaurant called The Alpine Lodge, at 8524 Sunset Boulevard. They hired Dean’s brother Bill to manage the place, and renamed it Dino’s Lodge.

Outside they put up a large neon sign, a likeness of Dean’s face. The sign turned into a national symbol of hip and cool, thanks to appearances on TV shows like Dragnet, The Andy Griffith Show, and most prominently, in the opening credits of 77 Sunset Strip.

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Dino’s Lodge was popular from the get-go, serving home-style Italian food and steaks in an intimate, candlelit, wood-paneled room meant to replicate Martin’s own den. In the first year, Dean himself frequented the place, signing autographs and posing for photos with starstruck diners. He also occasionally brought along famous friends like Frank Sinatra and Shirley MacLaine. To promote the idea of the swingin’ lifestyle that Martin often sang about, Dino’s served “an early morning breakfast from 1 to 5 a.m.” The restaurant also had a lounge that featured singers, though only females. Dean apparently didn’t want any male vocalists encroaching on his turf.

But as with many a celebrity venture into the food business, this one soon turned sour. And most of that was due to the jealousy of Jerry Lewis.


In late 1961, Lewis wooed Martin’s business partner Maury Samuels away, ponied up some $350,000, and opened his own copycat restaurant three blocks down Sunset. It was called Jerry’s. To make it clear he was out for top billing, Lewis had his own likeness rendered in neon, then mounted it on a revolving pole 100 feet above his restaurant. In contrast to Dino’s Italian-based menu, Jerry’s would serve “American and Hebrew viands.” Lewis didn’t stop there. Within a few months, he’d hired away Dino’s top two chefs, his maître d', and half his waitstaff.

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When Lewis was in Los Angeles, he made of point of table-hopping and schmoozing with his guests at his restaurant, and he occasionally brought in a few of his celebrity friends, like Peggy Lee and Steve McQueen.


By the following year, a disgusted Dean Martin was fed up with the restaurant business and cut ties with Dino’s Lodge. Much to his aggravation, he lost a motion in court to have his likeness and name removed from the sign. So the new owners carried on as Dino’s Lodge, with the big neon head staring down on Sunset for another decade before the place finally went bust.

Jerry’s lost steam long before that, folding in the mid-1960s.

For the rest of the 1960s and the early 1970s, Martin and Lewis avoided each other. “Jerry’s trying hard to be a director,” Dean once told a reporter. “He couldn’t even direct traffic.”

In 1976, Frank Sinatra famously engineered an onstage reunion of the pair during The Jerry Lewis Telethon. While the audience roared their approval, Sinatra said, “I think it’s about time, don’t you?” And to Sinatra, Lewis said under his breath, “You son of a bitch.”

What followed was an awkward few moments of shtick between the former partners. Reportedly, Martin was drunk and Lewis was doped up on painkillers. There was a quick embrace, Martin sang with Sinatra, then blew Lewis a kiss and disappeared from his life for good. Martin died in 1995. Lewis passed away today, at the age of 91.


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