ESA

This all-sky map from the Planck probe charts the imprint of the big bang's cosmic afterglow.

The Planck cosmology probe has forced scientists to revise their estimates of the universe's age and the cosmic balance of matter and dark energy — and now it's led a physicist to remix the sound of the big bang as well.

The new big-bang sound was created over the weekend by John Cramer, a professor emeritus of physics at the University of Washington. The audio file follows up on Cramer's decade-old audio rendition of the big bang, which was based on data from NASA's Wilkinson Microwave Anisotropy Probe, or WMAP.

Planck and WMAP both charted subtle variations in the all-sky cosmic microwave background, a super-faint glow of stretched-out radiation from a time when the universe was 380,000 years old. The variations amount to mere millionths of a degree in temperature, but they record the imprint of fluctuations left behind by the big bang.

Cramer released his original WMAP big-bang sound 10 years ago, but the Planck readings were so much better that a remix was in order.

"The new frequency spectrum goes to much higher frequencies than did the WMAP analysis, and therefore offers a more 'high-fidelity' rendition of the Sound of the Big Bang," Cramer explained on a Web page providing the updated sound files. We're featuring the 20-second version, but you can download versions that play out for as long as 500 seconds.

"I recommend the 100-second version, but you can choose for yourself," Cramer said.

The sound follows the curves in Planck data to reflect the propagation of pressure waves through the medium of the early universe during the first 760,000 years of its evolution. The time scale has been speeded up astronomically, of course, and Cramer figures that the frequency has been scaled up by a factor of 100 septillion (that's a 1 followed by 26 zeroes).

"The actual Big Bang frequencies, which had wavelengths on the order of a fraction of the size of the universe, were far too low to be heard by humans (even had any been around)," Cramer explained.

Ten years ago, Cramer said that when he played the sound of the WMAP data on his computer, his dogs pricked up their ears and listened attentively. "There was less reaction from the dogs this time, but there was some barking when the big bang sound initially came on," Cramer told NBC News in an email.

Sharp-eared listeners with a good sound system will notice that the Planck remix doesn't rattle the speakers as much as the WMAP original does. "The big bang sound is different because of the higher frequency components from Planck, and because I decided to shift the frequency scale factor to make less bass (since not everyone has a sub-woofer on their PC)," Cramer said.

In addition to the big-bang sound, Cramer has several unorthodox claims to scientific fame, including his long-running column for Analog magazine; his science-fiction novels, "Twistor" and "Einstein's Bridge"; and his experiment to find out whether quantum mechanics would allow for backward causality.

Cramer said his retrocausality experiment is currently in limbo. He has always said that there might be some subtle quantum effect that would rule out backward causality, and so far that's been the case.

"The Mark II version of the retrocausality experiment has concluded for now, defeated by detector noise," he said in his email. "I'm currently in the process of writing a new pre-proposal (to a government organization I won't name) seeking funding for a Mark III version of the experiment.  It would use noise-free superconducting-transition single photon detectors instead of the too-noisy avalanche photodiodes, would be down-scaled in wavelength a bit so that the entangled photon pairs would be at wavelengths matching the communication industry standard wavelengths for fiber optics, and would use two switched single-mode fiber optic Mach-Zehnder interferometers instead of lenses, prisms and mirrors on an optics table.  Said organization is interested because there is the possibility of zero-time-delay communication with distant space missions."

Read that last sentence again: Someone in the government is interested in zero-time-delay communication with distant space missions. Albert Einstein's theories suggest that information can't be transmitted any faster than the speed of light, but Einstein himself said quantum mechanics might open the door for "spooky action at a distance." Zero-time-delay communication certainly sounds spooky — but is it possible? Stay tuned.

Scott Eklund / Seattle P-I file

University of Washington physicist John Cramer, seen here in a 2007 photo, has been working on a laser experiment to test whether causality can work backward in time.

More weird physics:

• Math twisted for faster-than-light travel
• Bizarre quantum physics may play role in life
• New view: Big bang was a big crystallization

Audio clips: Copyright 2013 John G. Cramer.

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

Scott Thompson / Maryhill Museum file

Maryhill Museum's concrete replica of Stonehenge was designed to duplicate the ancient English monument.

British researchers conducted experiments at a Stonehenge stand-in as well as the actual 5,000-year-old monument to determine how sounds echoed within the ancient circle of stones — and they found that the sounds would have taken on an eerie reverberation.

"We can expect such a space to have a striking effect on someone of that time, identical to what we feel nowadays when we go into a church," the University of Salford's Bruno Fazenda, who orchestrated the research project, told me in an email.

The study is described on the university's website in a technical analysis as well as a news release issued last week, but the upshot is that the Neolithic people who gathered inside the circle could well have had a religious aural experience. That meshes with the view of most archaeologists that the monument on England's Salisbury Plain took on the trappings of a place of healing — a "Neolithic Lourdes," if you will.

It's not easy to reconstruct the sounds of ancient Stonehenge: For one thing, many of the standing stones are missing from what was thought to be their original places, ruining the acoustic arrangement. For another thing, researchers are not allowed to run electrical power out to the site, or bring in a generator. That limits the types of sound equipment and scientific instruments that can be used on site.

Replicating the reverb
Fazenda and his colleagues from the University of Huddersfield and the University of Bristol found a couple of clever solutions to those challenges. They brought air-filled balloons to the Stonehenge site in 2009, then popped the balloons with a needle and recorded the reverb with a microphone and a digital field recorder. The reflected sounds of the pops were hard to make out, but they appeared to follow a pattern of 1-second reverberation time at midfrequencies, for locations that were within the ruins of the stone circle.

To study the reverberation patterns in detail, the team headed off to the Maryhill Museum in Goldendale, Wash., which has a full-scale concrete replica of Stonehenge on its grounds. The monument was built by millionaire industrialist Samuel Hill as a tribute to fallen World War I servicemen. The museum let the researchers make their measurements with more sensitive instruments, powered by on-site generators. The same balloon-popping technique was used, and the readings confirmed the reverberation pattern that the team found at the real Stonehenge.

"For an outdoor space, the stone circle exhibits quite a 'live' acoustic environment," Fazenda said. "In the Neolithic, such an environment was not very common at all. The only spaces that might sustain reverberation were caves and perhaps some natural features such as opposing cliff faces."

Fazenda said the echo effect would be much more like what you hear in a cathedral than in a concert hall.

"The center of the space has potential for some focusing effects," he said. "That's the point where all reflections arrive at the same time, and with the largest gap relative to direct sound. On paper we would expect that to sound striking. However, there are quite a lot of scattering effects from the stones, so the clear echoes are somewhat destroyed by it."

He stressed that it's not at all clear whether Stonehenge was designed with the acoustics in mind, but he and his colleagues do think that the setting would have added a special something to drumbeats, chants or music inside the stone circle.   

'Research hobby'
Fazenda, who teaches audio production at Salford, has been working on this project for the past four years on an unfunded basis. "It has been a kind of 'research hobby' that I have managed to do after hours (don't really call it spare time)," he wrote. He believes the project could break new ground in the field of archaeoacoustics — the study of the sound characteristics of ancient spaces.

"The original focus was on studying the acoustic response of the space," he said. "The recent output has been that we replicated it using wavefield synthesis, which immerses you in a sound field, thus giving you the most approximate aural experience that you could get of being in the space. That was shown at a few recent events, and we have a permanent demo in our labs here at Salford. A wavefield synthesis system uses +64 channels and speakers, so it is not really portable."

Such a system can be tuned to provide a virtual-reality sense of the sounds of Stonehenge, as well as the sounds of other ancient settings that are no longer configured the way they were in their heyday. Want to hear the roar of the crowd in the Roman Colosseum? There's a wavefield synthesis app for that.

Fazenda is preparing a paper on his "research hobby" for Acta Acustica, the journal of the European Acoustics Association. He's also writing a chapter for a book on the acoustics and music of British prehistory. (For more on that subject, check out the website of the Acoustics and Music of British Prehistory Research Network.)

You can expect to hear more about the sounds of Stonehenge in the months and years ahead. In the meantime, give a listen to these sound files, and follow the Web links for more about archaeoacoustics.

Stonehenge sound files:

• Hand-clapping outside and inside the Maryhill stone circle (via Sonic Wonders)
• Univ. of Salford's rendering of a song with Stonehenge-style reverb (WAV file)
• Sounds of Stonehenge ... including a podcast on sound heritage

More about archaeoacoustics:

• Scientists revive sacred sounds
• Was Stonehenge inspired by a sound illusion?
• It turns out that cavemen loved to sing
• Stonehenge: Totally awesome place for raves
• Researchers re-create scary pre-Columbian sounds
• Acoustic archaeology yields mind-tripping tricks
• Listen to the sounds of science

Alan Boyle is msnbc.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter or adding Cosmic Log's Google+ page to your circle. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for other worlds.

NASA file

Astronauts on Mars would probably speak with each other on the surface through radio links — but if they were to pick up voices or sounds transmitted through Martian air, would they sound different? Acoustics experts say they would.

If you could speak on Venus, you might sound like a deep-voiced Smurf — while on Mars, your voice could have the shallow ring of a higher-pitched Shrek. And if you enjoy the sound of a waterfall on Earth, wait until you hear what that tinkling would sound like on Titan. Researchers at the University of Southampton have simulated all these sounds, based on the physics of planetary atmospheres.

"This is the real deal," Tim Leighton, an acoustics professor at the British university, said in a news release. "It's as close as we can get to the real sound of another world until a future probe or astronaut actually goes there and listens to what it really sounds like."

The sounds are being shown off over the next week at the Astrium Planetarium at INTECH, near Winchester, as part of a show titled "Flight Through the Universe."

"Hearing the sounds communicates ideas about the different atmospheres and highlights the sheer alienness of the other worlds in our solar system," planetarium manager Jenny Shipway said. "There is interest in this software from other planetariums worldwide, and we're very proud to be hosting this world first."

Simulation software
Leighton and his colleagues have been developing the audio simulation software for years, in part to determine what sounds a Titan probe might record if it were to splash down in a lake of hydrocarbons during a future space mission. The software can tweak the pitch and timbre of sounds ranging from thunder and whirlwinds to music and the human voice, depending on atmospheric composition, pressure and fluid dynamics.

"On Venus, the pitch of your voice would become much deeper," Leighton said. "That is because the planet's dense atmosphere means that the vocal cords vibrate more slowly through this 'gassy soup.' However, the speed of sound in the atmosphere on Venus is much faster than it is on Earth, and this tricks the way our brain interprets the size of a speaker."

He suggests that our brain has been fine-tuned this way "to work out whether an animal call in the night was something that was small enough to eat, or so big as to be dangerous." On other planets, however, that fine tuning can lead to different impressions.

"When we hear a voice from Venus, we think the speaker is small, but with a deep bass voice," Leighton said. "On Venus, humans sound like bass Smurfs."

He said the situation would be different on Mars. "The lower sound speed on Mars does not lower the pitch of the voice," Leighton told me in a follow-up email. "It makes the speaker seem slightly larger, but still in pitch. In fact, the atmosphere of Mars would raise the pitch of the speaker's voice slightly, because of a density effect."

Microphone missions
Other groups have produced simulations of extraterrestrial sounds, based on their own assumptions about atmospheric effects. The nonprofit Planetary Society actually helped set up experiments to record and send back sounds from the Martian surface — but one mission that carried the Mars Microphone failed (Mars Polar Lander, in 1999), while a French mission that was due to carry another microphone was canceled (Netlander). NASA's Phoenix Mars Lander had a small microphone on its Mars Descent Imager, but it produced no data during that 2008 mission.

Leighton told me he didn't think the Planetary Society's simulated sounds were quite right, and he sent along a sampling of his own simulations. The differences between the sounds are actually subtler than I expected them to be, except for the Titanian waterfall, which actually sounds pretty alien. See what you think after listening to these sound clips:

• A reading of "Mary Had a Little Lamb," Earth-style
• "Mary Had a Little Lamb" on Venus
• "Mary Had a Little Lamb" on Mars
• "Mary Had a Little Lamb" on Titan
•  Waterfall on Earth, and the simulated analog on Titan
• Simulated rumble of thunder on Earth, Mars and Venus
• Simulated crash of thunder on Earth, Mars and Venus
• Splashdown of probe in Earth lake and in Titan lake
• The simulated winds of a Martian dust devil

More about the sounds of space:

• Solar storm soundtrack recorded on video
• Video: Hear the sound of a black hole
• The sights and sounds of space

In addition to Leighton, the Southampton team members who are researching extraterrestrial acoustics include Professor Paul White and M.Sc. students Nikhil Banda and Benoit Berges. Leighton has also worked with Andi Petculescu at the University of Louisiana at Lafayette to study how voices and musical instruments would sound on other worlds.

Alan Boyle is msnbc.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter or adding Cosmic Log's Google+ page to your circle. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for other worlds.