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Just how loud is a rocket launch?



The massive thrust needed to launch a rocket into space creates a lot of noise. How much?

Watch footage of the Saturn V launches during Nasa’s Apollo programme in the 1960s and 1970s, and one thing that may strike you – even more than the polyester-heavy fashions and retro haircuts – is just how far away the crowds of onlookers are from the main event.

There were several good reasons for this, and noise was one of them: loud sounds can kill, and few things built by humans have been as loud as the Saturn V.

When Apollo astronauts blasted off on their missions to the Moon, they did so with more than 3.2 miles (5.1km) separating them from the excited, onlooking crowds. Even at such distances, the noise was incredible. A common myth at the time was that the soundwaves from the Saturn V’s engines were so powerful that they melted concrete on the launch pad and set fire to grass a mile (1.6km) away (both were false).

Nasa’s measurements at the time captured the launch noise at 204 decibels. Compare that to the sound of a jet airliner taking off, which is between 120 and 160 decibels and considered dangerous to hearing if endured for longer than 30 seconds. Even 1.5 miles (2.4km) away, the noise from a Saturn V launch was recorded as being 120 decibels – as loud as a rock concert, or a car horn at very close quarters.


“I’m always struck by the physicality of a launch,” says Anthony Rue, a Florida café owner who has been watching and photographing launches since the days of Saturn V. “Back in the 1970s there was an audio device called Sensurround that was used in disaster movies like Earthquake to create a subsonic seismic ‘experience’ in the theatre.

“Launches, from up close, are a bit like Sensurround,” says Rue. “You can feel a slight tremble, then a building rumble in your chest before you can hear any actual sound. The subsonic bass frequencies make your ears crackle. After a few seconds, the sound coalesces into a roar, like a massive welding torch.”

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Last year, a team of scientists from Brigham Young University in Utah calculated just how loud Saturn V was. They came up with a remarkably similar finding to Nasa’s own recordings – 203 decibels.

The difference between 160 and 200-odd decibels might not sound like a lot in the grand scheme of things, but it is.

“One hundred and seventy decibels would be equivalent to 10 aircraft engines. Two hundred would be 10,000 engines,” said Kent Gee, leader author of the study and professor of physics at the Brigham Young University at the time. “Every 10 decibels is an order-of-magnitude increase.”

Artemis’s SLS rocket emits a similar amount of thrust as the Apollo programme’s Saturn V (Credit: Anadolu Agency/Getty Images)

Was Saturn V the loudest rocket ever launched? Probably not, if you use thrust as your guide. The 35MN (meganewtons) of force produced by Saturn V at launch is less than that produced by the Soviet Union’s ill-fated N1 rocket (45MN) which was supposed to have delivered cosmonauts to the lunar surface in the 1960s. But it was certainly loud enough that there was more to consider than just the hearing of spectators. Rockets as powerful as Saturn V were capable of causing damage to themselves just from the soundwaves generated from the noise of their own launch.

Making sure that damage didn’t happen preoccupied Nasa’s rocket engineers even before the Apollo programme, says Nasa’s John Blevins, chief engineer of the Space Launch System (SLS) used for the recent Artemis programme launch.

One solution: the fire trenches in the launch pad are filled with water which helps muffle some of the intense noise created when the rocket lifts off.

“There’s a series of ground tests that we did back in the Apollo days, we did them again for Space Launch System,” says Blevins, adding that Nasa also built smaller models of both the rocket and the pads to gauge how their interactions produced noise. “The maximum noise for the rocket itself, although you might not be able to tell if you’re sitting at Banana Creek [a popular site for viewing launches], is actually about 150ft (45m) off the ground; the plume is spread out, instead of going down a hole that has the water in it, that helps attenuate some of that noise.”

The water-filled fire trenches were also used for the Space Shuttle launch – the charismatic, boiling clouds of vapour seen in those famous old Nasa rocket launches are not in fact smoke, but steam from the water vaporising from the intense heat.

The SLS is the new rocket used in the Artemis programme – the one planned to take humanity further into the Solar System than ever before. As the SLS chief engineer, Blevins has watched – and heard – its five engines being ground tested at the John C Stennis Space Center in southern Mississippi. The ground tests are a critical step in a rocket design’s progress, says Blevins.

“I’m about a half mile away, I’ve got earplugs in and for 600 seconds, this thing is producing just more steam than you can imagine. And when you can get that close, you see that’s one engine out of four! And those produce less thrust than the two [solid rocket boosters] on the side.

“It gives you an idea just how powerful these rockets are. It’s just amazing.”

The huge white clouds created during launches like the ones seen here are from water which is there to muffle some of the noise (Credit: HUM Images/Getty Images)

The huge white clouds created during launches like the ones seen here are from water which is there to muffle some of the noise (Credit: HUM Images/Getty Images)

Blevins says the SLS is quieter than Saturn V, but that noise levels are dependent on more than just the engine’s thrust.

“There’s a lot of nuances to what the people hear. Like a low cloudy day, like if you had a 1,000ft (330m) cloud ceiling, that noise will travel all the way across the state of Florida and just bounce back and forth. It really won’t be easily attenuated and so people in Tampa will hear a rocket launch if you have a little overcast day.” Tampa is three hours’ drive away from the Kennedy Space Center, on the other side of the Florida peninsula.

Noisier rockets may indeed be on the cards. SpaceX’s Starship vehicle – intended for a proposed mission to Mars – will lift off on top of the company’s Super Heavy booster. Super Heavy will, according to SpaceX, generate nearly 76MN of thrust, more than twice that of Saturn V. If you’re planning on watching it take off, earplugs sound like a very good idea.



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Is Shimano about to ditch derailleur hangers? Patent reveals direct-mount derailleur design



Shimano looks to be following SRAM with a direct-mount derailleur design

A patent application filed by Shimano appears to show that the brand is working on an integrated rear derailleur, similar to what we’ve seen on SRAM’s new T-Type Eagle Transmission.

The patent drawing shows a clamp design with the derailleur fitting directly onto the rear dropout, removing the need for a derailleur hanger, and held in place by the thru-axle.


The patent application hints at Shimano moving to a design similar to SRAM’s direct-mount T-Type rear derailleur.

However, as with any patent application, concrete details are limited. It does, however, provide another hint as to where the future of high-end drivetrains may lie.

Here’s what we know so far.

What is SRAM T-Type?

SRAM’s new T-Type Eagle Transmission uses a direct-mount rear derailleur. Ian Linton / Our Media

Before, we look at Shimano’s patent, let’s quickly cast an eye back at SRAM’s new T-Type Eagle Transmission, launched only last week.

In one of the most significant developments in drivetrain design in a number of years, T-Type Eagle combines SRAM’s existing Universal Derailleur Hanger standard with a new, direct-mount rear derailleur.

The new derailleur has no B-tension or limit screw adjustment, and doesn’t need a derailleur hanger. Instead, it mounts directly to the bike’s frame at the dropout.

The derailleur has user-replaceable components and, all told, SRAM says the new T-Type Transmission is intended to increase drivetrain robustness and reliability, improve shifting under load and offer easier setup. (How does it perform? Read our SRAM T-Type Eagle review).

So what about Shimano?

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What has Shimano patented?

Shimano’s hanger patent drawing, showing the thru-axle threaded into the frame. Shimano

Shimano’s patent drawing shows a design for the mounting of a derailleur “coaxially” to the rear wheel of a bike.

Shimano says the purpose of the patent is “to provide a rear derailleur with improved usability”.

The derailleur mount is attached coaxially to the rear axle. Shimano

Key to this is what Shimano describes as an “‘angular position structure”. This looks similar to a B-gap screw on the rear of the mount and will likely be used for the initial setup of the rear derailleur.

This could also suggest that Shimano’s design is intended to work with different cassette sizes. By comparison, SRAM’s T-Type derailleur forgoes the B-gap screw as it is designed to specifically work with a 10-52t cassette.

A screw is used to set the angular adjustment of the derailleur. Shimano

Shimano says the B-gap screw improves usability because it “allows for easy adjustment of the angular position of the rear derailleur relative to the frame of the bicycle”.

The patent application shows the setup tool needed. This measures the number of teeth on the cassette to help line up the derailleur correctly.

The patent document also specifies the thickness of the two arms that fit around the dropout. It says these arms will have a radial thickness of at least 2mm to increase the rigidity of the rear derailleur.

How does Shimano’s patent compare to SRAM T-Type?

Is Shimano working on a direct-mount rear derailleur? Shimano

Shimano’s patent depicts a similar-looking design to SRAM’s T-Type rear derailleur.

Notably, Shimano’s drawing shows two arms sandwiching the rear dropout.

SRAM’s T-Type is mounted around the axle, enabling it to work with a wide range of bikes that use the UDH dropout. Ian Linton / Our Media

As with the T-Type mount, Shimano’s patent drawing shows the rear axle screwing into a thread used to mount the derailleur, centring the derailleur around a constant point of reference.

Ahead of launching the T-Type Eagle Transmission, SRAM introduced the Universal Derailleur Hanger dropout standard in 2019.

A bike must use UDH in order to be compatible with SRAM T-Type’s Hangerless Interface and, in turn, accept the T-Type rear derailleur.

Shimano’s drawings hint at a similar design, though at this stage we’re unable to comment on how it might influence frame design and, significantly, any cross-compatibility with SRAM’s UDH standard.

Will Shimano go direct-mount?

Shimano’s drawing shows the design depicted on a mountain bike. Shimano

This patent application suggests Shimano may add a true direct-mount option to its mountain bike range.

On the one hand, Shimano appears to be following SRAM, but this would not be Shimano’s first foray into direct-mount derailleurs – at least in name.

Shimano’s Direct-Mount Rear Derailleur (DRD) standard, which debuted in 2012, replaced the upper link of traditional hangers, connecting the frame to the upper pivot of compatible derailleurs.

Shimano’s existing Direct-Mount Rear Derailleur (DRD) design replaced the upper link of traditional hangers. Shimano

However, this still sees the derailleur mounted below the dropout.

Shimano’s latest patent shows the first design from the Japanese firm whereby the derailleur is mounted directly to the axle/dropout.

Will we see Shimano’s patent come to life?

Well, we’ll have to wait and see on that one. A patent application doesn’t guarantee an end product and, while Shimano’s application was published in June 2022, we have no way of knowing whether anything has progressed since then.

But, given SRAM’s recent move with the public launch of T-Type, a direct-mount counter-punch from Shimano seems more likely than not.


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Microsoft Rolls Out New Version of Teams



For those who turn to tech stock leader Microsoft (NASDAQ:MSFT) and its Teams app for getting together with colleagues, today was a big day. Microsoft rolled out a new version and, with it, detailed monthly average users (MAUs) for the tool. Investors, however, weren’t particularly pleased, as Microsoft slipped slightly in Monday’s trading.

First off, the big score: Microsoft revealed that 280 million users a month are actively putting Teams to work. That figure is up from 270 million back in January and up from 250 million in July 2021. It’s also said to be about 14 times the users that Salesforce’s (NASDAQ:CRM) Slack boasts. Either way, that’s a lot of workers, but Microsoft didn’t stop there. It also noted that it was “…reimagining Teams from the ground up” to ultimately produce a newer, better Teams. The improved version would require fewer resources to run and also work better overall.

The new version of Teams is not only twice as fast as the previous versions, but it also requires just half the computing resources to run. Thus, those who keep Teams running in the background while working on documents, spreadsheets, or whatever will see better performance while they work. It also uses 70% less disc space, allowing more documents and spreadsheets on your local drives.

Overall, Microsoft stock is considered a Strong Buy by analyst consensus based on 26 Buy recommendations against four Holds and one Sell recommendation. Further, with an average price target of $292.48, Microsoft stock comes with 5.83% upside potential.




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Warner Bros brawler Multiversus to go offline in June 2023



MultiVersus, the online competitive platform fighting game from Warner Bros. and Player First Games will be temporarily closing its doors on 25 June 2023. The title, which features a number of characters from Warner Bros.-owned properties like Looney Tunes, DC Comics, Game of Thrones, Scooby-Doo, and several others, will be pulled offline with an aim to relaunch in early 2024, according to a statement from the company.

The news has come as a surprise to many, as the free-to-play game had been operating continuously since July 2022, with the ability to purchase virtual currencies, cosmetic items, and pricey ‘Founders Packs’ that offered a bounty of items and character unlocks. New characters were introduced somewhat regularly, and two seasons of Battle Pass content were offered.

When Multiversus closes in June 2023, it will have been in operation for almost a full year.

However, it’s important to keep in mind that this opening phase was framed as an ‘open beta’, and Player First Games appears to have no qualms in treating it as such. The game went through a closed beta stage in early 2022, before the ‘open beta’ began in July 2022.


Though the game saw particularly high player uptake when the open beta first launched – over 20 million players – by the end of 2022 it feels as if the player population – as well as new content – had dwindled.

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In a statement, Multiversus director Tony Huynh said that the studio knows ‘there’s still a lot of work to do’ on the game.

‘We have a clearer view of what we need to focus on, specifically the content cadence of new characters, maps, and modes to give you more ways to enjoy the game, along with updated netcode and more matchmaking improvements. We’ll also be reworking the progression system based on your feedback and looking at new ways for you to connect with your friends in the game.

After 25 June 2023, all online functionality in Multiversus will be unavailable, although offline training room and local multiplayer match functionality will still be available, along with access to any characters and cosmetic items that players have already unlocked.

Huynh assured that any and all progress that players have already unlocked in Multiversus would be carried over when the game relaunched next year.

A variety of ‘new content, features, and modes’ were promised for the 2024 relaunch.

We found Multiversus to be an entertaining take on the platform fighting genre, with some clever and interesting design choices that separated it from its competitors, and made for a more aggressive, dynamic game. Its focus on catering to high-level competitive play, despite the game’s clear intention to pull a broad, general audience with its characters, was much appreciated and seemingly well-received.

Though the temporary closure of the game is disappointing, given the dwindling playerbase, perhaps it’s what Multiversus needs to try and build in the longevity it needs to survive in a genre and community so heavily fixated on Nintendo‘s Super Smash Bros. series.



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