NASA: GPM's Dual-frequency Precipitation Radar

NASA Goddard receive Global Precipitation Measurement's (GPM) Dual-frequency Precipitation Radar from Japan's JAXA.

On Feb. 9, JAXA unveiled the dual frequency precipitation radar (DPR), which will be onboard the main satellite for the Global Precipitation Measurement (GPM) project.

A press conference was also held on the same day, and project personnel not only from JAXA, but also from the National Institute of Information and Communications Technology (NICT) and NASA explained the outline of the DPR and GPM main satellite.

They also described possible contributions from the GPM project to research elucidating climate and water circulation changes, improving weather forecast accuracy, and use in damage preparation caused by water and wind such as floods.

The DPR was transferred to NASA to be aboard the GPM main satellite. The satellite will be launched by the H-IIA Launch Vehicle from the Tanegashima Space Center.

Cell Phone Jammers: A Convenience or a crime?

A cell phone jammer is a small device that looks like a walkie-talkie. It is used to prevent cell phones from receiving signals from base stations.

Cell phone jammers block cell phone operations by sending radio waves along the same frequencies that cellular phones use. The radio waves cause interference between the cell phone and its ability to communicate with cell phone towers.

Cell phone jammers come in a variety of sizes, can affect large or small radiuses, and can target a variety of cell phone bands (frequencies used to communicate with towers).

Jammers either disrupt phone-to-tower frequencies or tower-to-phone frequencies. The latter is typically more effective.

Cell phone jammers are illegal according to FCC regulations. The reason is because cell phone jammers could prohibit emergency vehicles from communicating with each other.

It can also disrupt police communication and jammers may prohibit someone from reaching emergency services if they're used incorrectly.

Venice: Curly Pasta shaped Radiowaves to solve congestion

A group of Italian and Swedish researchers appears to have solved the problem of radio congestion by cleverly twisting radio waves into the shape of fusilli pasta, allowing a potentially infinite number of channels to be broadcast and received.

the researchers have demonstrated this in real-life conditions by beaming two twisted radio waves across the waters of Venice.

Their results have been reported today, Friday 2 March, in the Institute of Physics and German Physical Society's New Journal of Physics and are accompanied by a video abstract that gives an excellent insight into the authors' work.

As the world continues to adapt in the digital age, the introduction of new mobile smartphones, wireless internet and digital TVs means the number of radio frequency bands available to broadcast information gets smaller and smaller.

"You just have to try sending a text message at midnight on New Year's Eve to realise how congested the bands are," said lead author Dr Fabrizio Tamburini.

The researchers, from the University of Padova, Italy, and the Angstrom Laboratory, Sweden, devised a solution to this by manipulating waves so that they can hold more than one channel of information.

In addition to increasing the quantity of information being passed around our planet, this new discovery could also help lend an insight into objects far out in our galaxy. Black holes, for example, are constantly rotating and as waves pass them, they are forced to twist in line with the black hole.

According to Tamburini, analysing the incoming waves from the supermassive black hole at the centre of the Milky Way, Sagittarius A, could help astronomers obtain crucial information about the rotation of this "million-solar mass monster."

More information: "Encoding many channels on the same frequency through radio vorticity: first experimental test" Tamburini F et al 2012 New J. Phys. 14 033001 - http://iopscience. … 3001/article

What is up with Noises? The Science and Mathematics of Sound, Frequency, and Pitch - YouTube

Mathemagician Vi Hart creates another brilliant stop-motion movie, this time exploring the science and mathematics of sound, frequency and pitch. From Pythagoras to the anatomy of the ear, Hart uses her signature playful hand-illustrations to reveal how simple mathematical ratios make pleasing melodies.

Today's Lecture: Why is Space Black and the sky Blue?

A simple enough question but it is actually quite difficult to answer! It is a question that many scientists pondered for many centuries - including Johannes Kepler, Edmond Halley , and German physician-astronomer Wilhelm Olbers.

Let's take the easy one first and ask "why is the daytime sky blue here on Earth?"

That is a question we can answer. The daytime sky is blue because light from the nearby Sun hits molecules in the Earth's atmosphere and scatters off in all directions. The blue color of the sky is a result of this scattering process.

At night, when that part of Earth is facing away from the Sun, space looks black because there is no nearby bright source of light, like the Sun, to be scattered. If you were on the Moon, which has no atmosphere, the sky would be black both night and day. You can see this in photographs taken during the Apollo Moon landings.

So, now on to the harder part - if the Universe is full of stars, why doesn't the light from all of them add up to make the whole sky bright all the time?

It turns out that if the Universe was infinitely large and infinitely old, then we would expect the night sky to be bright from the light of all those stars. Every direction you looked in space you would be looking at a star. Yet we know from experience that space is black!

This paradox is known as Olbers' Paradox. It is a paradox because of the apparent contradiction between our expectation that the night sky be bright and our experience that it is black.

Many different explanations have been put forward to resolve Olbers' Paradox. The best solution at present is that the Universe is not infinitely old; it is somewhere around 15 billion years old. That means we can only see objects as far away as the distance light can travel in 15 billion years. The light from stars farther away than that has not yet had time to reach us and so can't contribute to making the sky bright.

Another reason that the sky may not be bright with the visible light of all the stars is because when a source of light is moving away from you, the wavelength of that light is made longer. This lengthening of the wavelength makes the light appear more red than blue.

This means that the light from stars that are moving away from us will become shifted towards red, and may shift so far that it is no longer visible at all. This is called the Doppler Effect or Dopler Shift.

The Human Eye

All living creatures on our planet have a limited range of light that they can detect and tolerate. There is an upper and lower threshold. If you look at it from the simple Goldilocks selectiveness perspective; some frequencies are too low, some are too high and some are just right.

Many birds, animals and insects can see very well in low light because they spend most of their time out of the sun. Therefore there ability to detect a fixed range of light is limited to the light that they most often hunt, live and work in, low light. This range selection will be part of their evolutionary development, allowing the animal to thrive, breed and prosper.

Equally, we humans exist mainly in the bright light of day, therefore the range or intensity of light that our eyes can detect are limited to the brighter end of the spectrum. We cannot and need not, detect low light ranges, we have devised other ways of penetrating the darkness. Our eyes have developed in such a way as to attenuate and normalise the intensity of light that we can detect, allowing us to function at our best, during the appropriate time of day.

What we cannot do, is to detect all light ranges and neither can other living creatures on the planet. There is no evolutionary 'advantage' to be gain from this. Therefore if the sky appears black to us, it is because there is simply not a high enough intensity or frequency of light entering the eye receptors, to stimulate a detectable reaction. It is not because there is no light present.

Artificial detection

We believe from science, astrophysics and our academic studies that the full range of light frequencies can be detected artificially by the use of intervening filters, attenuators and sensitive materials. We have enhanced our human vision by the use of these 'systems' and can penetrate the darkness and extend our perception of the universe and the night sky.

The night sky is not black it is simply bathed in a low frequency light that is difficult for us to detect, through the clouds and polluted atmosphere of our only planet.

In an Uncertain Universe: Perseids Meteor Storm is Reliable

The annual Perseid meteor shower is expected to put on a good show this week for those willing to get up in the wee hours of the morning and wait patiently for the shooting stars.

In North America, the best time to watch will be between midnight to 5 a.m. on Wednesday, Aug. 12, but late Tuesday night and also Wednesday night could prove fruitful, weather permitting.

The Perseids are always reliable, and sometimes rather spectacular. The only things that puts a damper on the August show are bad weather or bright moonlight. Unfortunately this week, as the Perseids reach their peak Tuesday and Wednesday nights, the moon will be high in the sky, outshining the fainter meteors.

Still, skywatchers around the globe will have a good chance of spotting the brighter meteors. Some already are enjoying the show.