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Blackmagic URSA 4K Digital Cinema Camera

And now that one special, prestigious piece of gear has finally arrived to round off the years of camera development and take you to the vertiginous peaks of unbelievable footage quality and extreme equipment versatility: the recently released Blackmagic URSA 4K Digital Cinema Camera is the ultimate camera for professional film crews and keen solo cameramen looking to revolutionize their filming sessions.

World ham radio prefix map

Experiment resolves mystery about wind flows on Jupiter

Using a spinning table and a massive garbage can, geophysicist leads team in simulating the planet’s atmosphere

One mystery has been whether the jets exist only in the planet’s upper atmosphere – much like Earth’s own jet streams – or whether they plunge into Jupiter’s gaseous interior. If the latter is true, it could reveal clues about the planet’s interior structure and internal dynamics.

Now, UCLA geophysicist Jonathan Aurnou and collaborators in Marseille, France, have simulated Jupiter’s jets in the laboratory for the first time. Their work demonstrates that the winds likely extend thousands of miles below Jupiter’s visible atmosphere.

This research is published online in Nature Physics.

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How do we know light is a wave?

Before I answer this question, I’ll need to briefly go over a wave property called superposition. Basically, superposition is the idea that two waves can be in the same position at the same time, and interfere with each other:

When the two waves add to each other and make a larger wave, we call this constructive interference. When the waves cancel each other out, we call this destructive interference. 

Now we’re going to move on to the Double Slit Experiment. Basically, you shine a beam of light at a piece of metal, cardboard, etc with two slits in it, with a surface behind it where you can see the light hit it. 

If light is a wave, what we’d expect to see would be an interference pattern created by the light from the first slit interfering with light from the second slit, which is exactly what we see. It’s a pattern of constructive interference (brighter regions) and destructive interference (darker regions), looking like this:

These images are helpful:

that is how we know light acts as a wave!!

I have waited a long goddamn time for this.

Fading Females

As the daughter of our town’s E.S.D.A. Coordinator, I have always been intrigued by ham radio. My father (and elmer) has been a ham for about 40 years. He actually received his license when he was in high school!

After studying for three weeks, I went to take the ham test. I was very discouraged to see that I was the only girl in the room. However, I was treated like a queen by the group that was hosting the test. They seemed excited to have a female in their midst.

Upon receiving my Technician license, I eagerly awaited the Tuesday night ARES net (which my dad happens to be the Net Control of). Again, I was saddened to hear but a few female voices. Over time, I noticed that the female hams rarely checked in to the net. I wondered why these women who worked so hard to achieve their licenses would not want to take advantage of all that ham radio has to offer.

I hope that women are being encouraged to be active hams. Whether they join a club or simply make contacts, females are providing a fresh voice and perspective to the hobby. So, ladies, do not be shy! Proudly check in with your call sign. You have earned it!

Explain this to me...

“Quantum cryptography uses the quantum properties of photons to guarantee perfect secrecy. But one of its lesser known limitations is that it only works if Alice and Bob are perfectly aligned so that they can carry out well-defined polarization measurements on the photons as they arrive. Physicists say that Alice and Bob must share the same reference frame. That’s OK if Alice and Bob are in their own ground-based labs, but it’s a problem in many other applications, such as ground-to-satellite communications or even in chip-to-chip communications, because it’s hard to keep chips still over distances of the order of the wavelength of light. Now a group of UK physicists have developed a way of doing quantum cryptography without sharing a reference frame. The trick is to use entangled triplets of photons, so-called qutrits, rather than entangled pairs. This solves the problem by embedding it in an extra abstract dimension, which is independent of space. So, as long as both Alice and Bob know the way in which all these abstract dimensions are related, the third provides a reference against which measurements of the other two can be made. That allows Alice and Bob to make any measurements they need without having to agree ahead of time on a frame of reference. That could be an important advance enabling the widespread use of quantum cryptography.”

General Ham: Digital Mode Introduction

This is probably a bit more repetition, but well worth the time!  So digital modes are where data are encoded as bits instead of in waves, and some are created commercially, while others are created by amateurs!  

Digital modes consist of two things: a protocol and a method of modulation.  A protocol is the set of rules that control the encoding, packaging, exchanging and decoding of digital data.  For example, packet radio uses the AX.25 protocol standard.  This standard says how each packet is constructed, how packets are exchanged, what characters are allowed, and so forth.  The protocol standard doesn’t say what kind of transmitter to use or what the signal will sound like on the air.

Digital mode signals are restricted to the CW/data segments of each band and most digital mode operation is close to the top of the CW segment.  Calling frequencies for the popular digital modes are incorporated into band plans and are usually the lowest frequency of operation with operators moving up in frequency as activity increases.

For example on 20m, most PSK31 signals are found near 14.070 MHz.  RTTY and other digital mode signals are found above that.  The modems used for digital signals often do not recognize signals from CW or other digital modes.

Here’s the Digital Signal Band Plan:

@atdiy/@tymkrs

H.J. Detouche’s 1754 painting depicting Galileo Galilei displaying his telescope to Leonardo Donato, Doge of Venice.

Mercury in enhanced color, imaged by MESSENGER  

Credit: NASA / JPL