Archive for the ‘Cool Stuff’ Category

Excited Cesium Atoms and the Radio Antenna

Wednesday, September 19th, 2018

Fascinating read about an atomic receiver for AM and FM radio communication, able to operate from the C- to the Q-bands, which may someday bring quantum physics into the world of satcom receivers.

Here’s more from MIT Technology Review

The secret sauce in the new device is Rydberg atoms. These are cesium atoms in which the outer electrons are so excited that they orbit the nucleus at great distance. At these distances, the electrons’ potential energy levels are extremely closely spaced, and this gives them special properties. Indeed, any small electric field can nudge them from one level to another.

Radio waves consist of alternating electric fields that readily interact with any Rydberg atoms they come across. This makes them potential sensors.

But how to detect this interaction? A gas made of Rydberg atoms has another property that turns out to be useful—it can be made transparent by a laser tuned to a specific frequency. This laser essentially saturates the gas’s ability to absorb light, allowing another laser beam to pass through it.

However, the critical frequency at which this happens depends crucially on the properties of the Rydberg atoms in the gas. When these atoms interact with radio waves, the critical frequency changes in response.

That’s the basis of the radio detection. Anderson and co create a gas of cesium atoms excited into Rydberg states. They then use a laser tuned to a specific frequency to make the gas transparent.

Finally, they shine a second laser through the gas and measure how much light is absorbed, to see how the transparency varies with ambient radio waves.

The signal from a simple light-sensitive photodiode then reveals the way the radio signals are frequency modulated or amplitude modulated.

And that’s it: an antenna consisting of a cloud of excited cesium atoms, zapped by laser light that flickers in time to any ambient radio waves. They call it atomic radio.

Very cool — and no electromagnetic interference!

I Fink You Freaky, Teletubbies

Monday, October 5th, 2015

It’s a Mad, Mad, Mad Max Fury Road

Friday, July 24th, 2015

Cracker-jack job, mate! One of my favorite movies, mashed-up into a trailer with Fury Road

Many thanks to Ezequiel López.

Road Trip: Kepler 452b

Friday, July 24th, 2015

NASA’s timed announcement yesterday got quite the bump from social media. It’s only one of 1,030 exoplanets, so let’s not get too excited.

NASA’s Kepler mission has confirmed the first near-Earth-size planet in the “habitable zone” around a sun-like star. This discovery and the introduction of 11 other new small habitable zone candidate planets mark another milestone in the journey to finding another “Earth.”

The newly discovered Kepler-452b is the smallest planet to date discovered orbiting in the habitable zone — the area around a star where liquid water could pool on the surface of an orbiting planet — of a G2-type star, like our sun. The confirmation of Kepler-452b brings the total number of confirmed planets to 1,030.

“On the 20th anniversary year of the discovery that proved other suns host planets, the Kepler exoplanet explorer has discovered a planet and star which most closely resemble the Earth and our Sun,” said John Grunsfeld, associate administrator of NASA’s Science Mission Directorate at the agency’s headquarters in Washington. “This exciting result brings us one step closer to finding an Earth 2.0.”

It’s also worth noting this planet is 1,400 light years away. Pluto, for comparison, is 4 light hours away. That’s why it took 4+ hours to send commands to the New Horizons spacecraft. So if we send a signal to Kepler 452b, it would take 1,400 years to get there.

To get to Kepler 452b at the same rate it took New Horizons to get to Pluto (10 years), it would take us approximately 30 million years. Ain’t nobody got time for that! The only way we could make this kind of trip is to be able to “fold space” or change dimensions. Heim Quantum Theory may help us get there by changing dimensions. Fascinating.

Two Launches in One Day!

Thursday, July 16th, 2015

Both Atlas V and Ariane 5 rockets went up recently. Both were equipped with rocketcams, but the weather was better at The Cape than in Kourou, so the Atlas launch’s lookback was really cool.

DIY Friday: Satellite Skate Park

Friday, July 10th, 2015

Old C-band dishes do make good skate park features, which showed up on this Mashable piece on skateboarders who never made to pro.

Watch this documentary on skateboarding from Boston to New York.

11+ Years of Mars Roving in 8 Minutes

Wednesday, July 8th, 2015

Brilliant time-lapse video covering NASA’s Mars Opportunity Rover’s 26-mile trip over the last 11 years.

Audi’s Jet-Fighter Mode

Friday, June 26th, 2015

Yes, this has been around for a while, but it’s still very cool.

Hendo Hoverboard

Wednesday, June 17th, 2015

Nice work by Hendo Hover, which people got to try at Smithsonian’s “The Future is Here 2015” festival last month.

Here’s Tony Hawk’s go at it…

Taco Tuesday in Space!

Tuesday, June 9th, 2015

Putting together a taco on the ISS is not a simple matter. With mackerel, leek cream, dried tomatoes and quinoa salad? Interesting.