Experience the beauty of the Northern Lights like never before with the FG-3+ sensor and AU-100 device from The Northern Lights, also known as Aurora borealis, are a captivating natural phenomenon that can be observed both at night and during the day. To fully appreciate and understand the aurora, it is essential to be aware of the current auroral activity in your area in real-time.

The FG-3+ sensor by is a magnetometer that measures the strength and direction of the Earth’s magnetic field. It is known for its sensitivity and affordability. The AU-100 device by is a high-precision instrument that enables seamless communication between the FG3 sensor and It boasts a user-friendly interface and display that clearly shows current readings from the magnetometer, as well as easy-to-configure settings. The device connects to via an Ethernet cable and is equipped with three LED lights that provide real-time updates on geomagnetic activity levels. The green light indicates normal activity, the yellow light indicates increased activity, and the red light indicates high activity. It also has an audible alarm that sounds when high levels of activity are detected.

To ensure accurate readings, the magnetometer sensor should be placed far away from any magnetic disturbances, at least 50 meters away from any moving metal objects. It should also be placed in a temperature-stable environment, such as 40cm below the ground, where the temperature is stable enough. An adapter board with a power supply and transmitter is used to send the signal back to the AU-100, and a typical Ethernet cable is used to connect the sensor to the AU-100. With the FG-3+ sensor and the AU-100 device, you can easily monitor auroral activity and be ready to witness the beauty of the Northern Lights.


The AU-100 device is a custom-engineered hardware that utilizes embedded software to provide precise measurements while maintaining energy efficiency. It is designed to work seamlessly with the FG-3+ sensor and to deliver real-time updates on auroral activity. The device is optimized for low power consumption and can be used in remote locations.

On the other hand, is a cloud-based application that utilizes the power and scalability of Amazon Web Services (AWS) to provide easy access to the data gathered by the AU-100 device. This allows users to remotely monitor auroral activity and access readings from any location with an internet connection. The combination of the AU-100 device and creates a comprehensive and dependable solution for monitoring the Northern Lights.

In the future, plans to include email services, which will allow users to receive alerts and updates on auroral activity via email. This feature will provide an additional level of convenience and accessibility, making it even easier to stay informed and be ready to witness the beauty of the Northern Lights.

Functional description of AU-100

The AU-100 device is powered by a standard USB power supply, which accepts voltage inputs between 4 and 6 volts DC and has a maximum current draw of less than 100mA. To ensure optimal performance and stability, the 5V USB power is regulated down to 3.3V using a highly efficient buck regulator, which is then used to power most of the device’s internal components, including the microcontroller unit (MCU) and the ethernet physical layer (PHY). Additionally, the 5V USB power is boosted up to between 12 and 14V to provide power to the remote sensor board, buzzer, and OLED display.

The device is built around the Microchip/Atmel SAME54 MCU, which features an M4F core and operates at a frequency of 25MHz. It has 1MB of flash memory and 256KB of RAM, and key features include Dual Bank Read While Writing to support remote updates, USB, Ethernet MAC, and ample clocks, timers, and counters.

An external EEPROM allows for non-volatile storage of user configuration data, enabling the device to retain its settings even after power loss and provides a unique MAC address required for connecting to the ethernet. This unique MAC address is also the foundation of the Device ID used throughout the device’s software.

To ensure a stable frequency reference for using the FGM sensor, a highly stable oscillator and dedicated LDO regulator are employed. The oscillator runs at 25MHz and this clock source is utilized throughout the device, including the Ethernet PHY and MCU frequencies. The stable clock source ensures accurate and reliable measurements.

The device also includes an on-board buzzer, driven by a PWM signal, for an audible alarm. The front-end user interface communicates via I2C and is based on a GPIO extension chip.The OLED display also uses the same I2C bus, and both 3.3V and 13.6V power is supplied to the front board, in addition to a hardware reset and interrupt signal. The user interface allows for easy monitoring and control of the device’s functions.

Communication with the sensor board is based on a differential signal received from the sensor board. The sensor board is supplied by the 13.6V rail, and the voltage is regulated down to approximately 6V. This 6V is used for an RS485 transmitter, which takes the single-ended signal from the FGM sensor and translates it to a differential signal. To ensure a stable voltage for the FGM sensor, a dedicated stable LDO regulator is used to regulate the voltage down to 5V. The differential signal provides improved noise immunity and longer cable runs while the FGM sensor provides high-precision measurement.

Finally, the device features several expansion slots for future relay output, external frequency input, and audible output.
These expansion slots allow for the device to be easily upgraded and expanded as required.

The AU-100 software is designed to measure geomagnetic activity from an FGM sensor. The software has the ability to measure frequency at the micro Hz level, which is then converted to a nT scale. The software uses an algorithm to determine the level of activity based on the changes in the magnetic field over a given period of time, measured in nT/s. The frequency measurement is continuous and takes approximately 5 seconds to complete.

The local user interface is updated after the measurement is complete, and a JSON object is created and securely transferred to The user interface allows the user to set the alarm level, a good starting point is 1nT/s, and also to set the location using GPS coordinates. These locations are used to place the device on the map.

The software can be upgraded by user initiation if required. The software package is downloaded automatically from The software package is encrypted, and after decryption, the authenticity of the package is checked. Authentication towards the server is validated using certificates, and encrypted.

The AU-100 establishes a secure connection with every 10 seconds using a combination of standard network protocols and secure communication methods. The device is configured with a minimal set of services that are essential for its operation, these include:

  • DHCP client for acquiring an IP address dynamically from the network.
  • DNS client for resolving the domain name of to an IP address.
  • NTP client for synchronizing the device’s clock with a time server, which is crucial for ensuring accurate timestamps on data transmissions.

In terms of network security, the AU-100 is designed with a “zero trust” principle, which means that it does not open any ports and is not configured to respond to network ping requests. Additionally, no port forwarding or public IP addresses are required for the device to function properly. The device uses certificate-based authentication and secure communication protocols such as TLS 1.2 to encrypt data transmission between the device and

Functional description of the web application

The is a highly advanced, cloud-native application that is specifically designed to operate within the AWS Cloud services ecosystem. The front-end of the application is served from an S3 bucket with a Cloudfront distribution acting as a proxy, while the API is based on the API Gateway and triggers various Lambda functions. The functional Lambda code is written in Python, which is a powerful and versatile programming language.

To enhance the performance and scalability of the application, precompiled map tiles are served from S3. Using precompiled tiles eliminates the need for an expensive EC2 instance, thus reducing costs and maximizing efficiency.

The application utilizes two different data storage mechanisms, DynamoDB and an Aurora Serverless V2 MySQL database, providing a high level of data durability and accessibility.

The entire AWS instance is fully configured using IAS (Infrastructure As Code) with Terraform as the tool, enabling easy management and maintenance of the infrastructure.

The front-end of the application is built on bootstrap/JQuery and is fully responsive, ensuring a seamless user experience on all devices. The application includes a “Desktop First” approach which prioritizes the desktop version of the website before mobile version. Additionally, the application has No tracking Cookies, ensuring the privacy of the users.

Geomagnetic Disturbances

The Earth’s magnetic field, also known as the geomagnetic field, is generated by the motion of molten iron in the Earth’s core. This motion creates a self-sustaining magnetic field that surrounds the Earth, similar to the way a bar magnet creates a magnetic field around it. The Earth’s magnetic field is not a simple dipole field, like a bar magnet, but a more complex and dynamic field that is constantly changing. The magnetic field strength varies depending on location, and it can change over time as well. This is because the Earth’s core is not a solid ball, but a fluid one, with convection currents that are constantly changing and therefore changing the magnetic field.

A geomagnetic storm is a temporary disturbance of the Earth’s magnetic field caused by a solar wind shock wave and/or cloud of magnetic field that interacts with the Earth’s magnetic field. These disturbances are caused by changes in solar wind conditions and can cause changes in the Earth’s magnetic field, which can lead to auroras, power grid fluctuations, satellite navigation errors, and other effects.

Solar flares and coronal mass ejections (CMEs) are two types of solar activity that can cause geomagnetic storms. Solar flares are explosive events that occur near sunspots, where intense magnetic fields are present. They release large amounts of energy, primarily in the form of X-rays and ultraviolet radiation, which can cause disturbances in the Earth’s magnetic field. CMEs are eruptions of plasma and magnetic field from the sun’s corona. They can cause a shock wave in the solar wind and a cloud of magnetic field that can interact with the Earth’s magnetic field, leading to a geomagnetic storm.
Geomagnetic disturbances can have a number of consequences, some of which can be observed directly and others that can have more subtle effects.

One of the most visually striking effects of geomagnetic disturbances is the appearance of auroras, also known as the Northern and Southern Lights. These are natural light displays that occur in the upper atmosphere when charged particles from the sun collide with atoms and molecules in the Earth’s atmosphere. During a geomagnetic storm, the increased number of charged particles in the Earth’s magnetic field can lead to brighter and more extensive auroral displays.

Another consequence of geomagnetic disturbances is the effect on radio propagation. The ionosphere is a layer of the Earth’s upper atmosphere that is ionized by solar radiation. It plays an important role in radio communication, including for Ham radio operators. During a geomagnetic storm, the ionosphere can become disturbed, leading to changes in the way radio waves propagate. This can cause a phenomenon known as ionospheric scintillation, where radio signals become rapidly fluctuating and can result in fading or complete signal loss. This effect can be more severe at high latitudes, near the auroral zones, and can be especially problematic for high frequency (HF) radio communication.

Also, geomagnetic storms can cause power grid fluctuations. The currents in the Earth’s magnetic field can induce currents in long conductors, such as power lines, which can cause equipment damage and power outages. These events can also cause damage to satellites and their equipment in orbit.


National Oceanic and Atmospheric Administration (NOAA) - Geomagnetic Storms
NASA - Aurora: The Northern and Southern Lights
European Space Agency (ESA) - Earth's magnetic field
American Radio Relay League (ARRL) - Ionospheric Propagation
American Radio Relay League (ARRL) - Solar-Terrestrial Data

About this project

This is a personal project that I have been working on since 2012, with breaks in between. The project is a reflection of my interest in creating innovative solutions and my passion for electronics, full-stack development and product development. Throughout the years, I have honed my skills in various technologies, including microprocessors, AWS infrastructure, and product design and development.

My focus on this project has been on continuous learning and personal development. I have been continuously challenging myself to push the boundaries of my skills and knowledge, and to apply new technologies in order to create innovative and practical solutions. I enjoy the process of taking an idea and turning it into a functional product, and this project has been a great way to pursue my interest and hobby in this field.

Status early 2023

This project has been ongoing for several years and continues to evolve with each dedicated period of time. Recently, during the early weeks of 2023, a concentrated effort was made to bring significant advancements to the project. As the availability of necessary components improves, plans are in place to acquire additional equipment, with the ultimate goal of expanding the network’s reach. If you believe you have a location that would be suitable for the project, please do not hesitate to contact me for further discussions.