Free communication in remote areas using balloons: Project Loon

The idea of using the stratosphere for improving communications was introduced and tested almost a decade ago. The European project Capaninia developed wireless and broadband technologies for use on high altitude platforms (HAP) floating at an altitude around 20 km. HAPs float above aircrafts, but below satellites. Thus, they do not interfere with any device. The main purpose was to provide low cost communications to remote areas.

Some days ago Google announced  its Loon project. Project Loon is a network of balloons that will provide internet and communications to rural and remote areas. The project will fill coverage gaps and bring people back online after disasters. The balloon-balloon and balloon-ground communication are be obtained through radio frequency using ISM bands between  2.4 and 5.8 GHz. Each balloon can provide service to an area up to 40 km diameter, with a speed equivalent to 3G (Image 1).

Image 1. Baloon-balloon and balloon-ground communication
Image Source: Project Loon

How it works?
The balloons are made of polyethylene plastic sheets. Once fully inflated, they are 15 m wide and 12 m high. Each unit is powered by solar panels able to produce up to 100 Watts. Besides, the panels also charge a battery for night use; hence, each unit is able to work the whole day by using only renewable energy.
Each unit also has a box containing the circuit boards that control the system, batteries to operate at night, radio antennas to communicate with other balloons, and the internet antennas to provide the service.

Project Loon takes advantage of the fact that winds in the stratosphere are usually steady and slow, with velocities between  5 and 20 mph. Besides, it is stratified in layers with different wind direction and wind magnitude. Thus, dedicated algorithms determine the required direction of the balloon, so that the balloon will move to the layer with the required wind (Image 2).

Image 2. Balloons navigation according to the wind
Image Source: Project Loon

The following video (Animation 1) summarizes the project and its functioning.

Animation 1. Project Loon
Source: Project Loon

References & Further Reading
Google experiments with internet-bearing baloons
Google's loon project put balloon technology in spotligth
Stratospheric broadbans
The Loon project

Plastic pollution in oceans and also lakes

What is a garbage patch?

All the garbage produced will eventually end up in the oceans and major water bodies. Then, currents will turn it into micro particles and accumulate them into certain areas creating the so called garbage patch.

Plastic pollution poses a big threat to marine ecosystem because it looks like food to fish, birds and other creatures. Some animal eat the plastic, while other get stucked. This garbage is undigestible, and once swallowed it fills the animals stomach creating a fatal blockage.
plastic garbage patch
Image 1. Debris extracted from water bodies

Passphrase instead of password

A recent study reported that more than 90% of all passwords are vulnerable to being hacked in just seconds. Moreover, the 10 000 most common passwords were published, hence providing access to 98% of all secured accounts. That means that we are prone to being attacked and we must protect our data and our computers.
PC security
Image 1. Source: PCMag