Applied Planetary Radio Astronomy

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Jovian Radio Storms

Project Outline

Charged partical trajectory in Jupiter's magnetic field
Charged partical trajectory in Jupiter's magnetic field
Origin of the different frequency emissions in Jupiter's magnetic field
Origin of the different frequency emissions in Jupiter's magnetic field
Jupiter's A-, B- and C type radio burst
Jupiter's A-, B- and C type radio burst


The project is suitable for 1-2 practically oriented students with broad interests, who do not mind “getting their hands dirty” every now and then, in addition to the time spent in front of the PC.

  1. Contact persons – Georgi Genov, Kjetil Ullaland, Nikolai Østgaard, Kjell Aarsnes
  2. Aim - To learn basic radio astronomy, to modify an existing radio telescope amplifier (RTA), to build the telescope’s antennas and to establish observational procedures.
  3. Tasks
    • Modifying the existing RTA for automatic sweep of the frequency range;
    • Building the electronics required to establish the computer communication;
    • Building and set up of the antennas of the radio telescope;
    • Developing a simple software for data acquisition and preliminary data analysis;
    • Performing tests and developing observational procedures.
  4. Benefits – learn basic radio astronomy; get hands-on experience with applied electronics, data acquisition and data analysis, development of software for scientific purposes.
  5. Background

Two types of radio noise emitted by Jupiter have been detected – synchrotron and cyclotron. The latter is strong enough to be detected by small antennas on Earth’s surface. Charged particles spiraling around Jupiter’s magnetic field lines near both magnetic poles (top figure) produce this cyclotron radiation. These shortwave signals are often referred to as DAM, since they fall in the decameter wavelength range. At these higher latitudes, where Jupiter’s magnetic field reaches as far out as Io, its field lines sweep rapidly past the ions and electrons shed into Io’s torus. This induces DAM radiation along the surface of the cyclotron cone (given in magenta in the middle figure). Jupiter’s DAM frequency reaches a maximum of 39.5 MHz near Jupiter’s cloud tops. At twice Jupiter’s radius the frequency is 3 MHz. Intermediate frequencies are created between these two extreme distances. Jupiter radiates two distinctive types of radio signatures in the DAM frequency range:

  • L-bursts –long duration static sounding like the swoosh of the waves;
  • S-bursts – short duration static resembling the crackling of a campfire.

DAM radiation originates from at least 3 sources (A, B and C) that are fixed with respect to the planet’s rotating magnetic field. These sources are observed at around 20 MHz. They fall largely around one hemisphere (bottom figure). Source A is more than twice more likely to emit than either B or C. Jupiter’s magnetic storms depend on a combination of Io’s orbital position and the inclination of the respective radio source with respect to Earth.


Original Radio JOVE Project

  1. JOVE Receiver Documentation
  2. JOVE Antenna Documentation

Receivers - Construction and Theory

Antennae - Construction and Theory

Books

The Radio Sky and How to Observe It - by Jeff Lashley

Preface and Table of contents

Chapter 1 - The Radio Sun

Chapter 2 - Jupiter

Chapter 3 - Meteors and Meteor Streams

Chapter 4 - Beyond the Solar System

Chapter 5 - Antennae

Chapter 6 - Setting Up a Radio Astronomy Station

Chapter 7 - Radio Hardware Theory

Chapter 8 - Introduction to RF Electronics

Chapter 9 - Building a Very Low Frequency Solar Flare Monitor

Chapter 10 - Microwave Radio Telescope Projects

Chapter 11 - Building a Jupiter Radio Telescope

Chapter 12 - Building a Broad Band Solar Radio Telescope

Chapter 13 - Data Logging and Data Processing

Appendices - Formulae; Bibliography; Suppliers, Groups, and Societies; Glossary

Articles

Miscellaneous

Radio Frequency Bands

Band name Abbreviation Frequency Wavelength Usage
< 3 Hz > 100 000 km Natural and man-made electromagnetic noise
Extremely low frequency ELF 3 - 30 Hz 100 000 - 10 000 km Submarine communication
Super low frequency SLF 30 - 300 Hz 10 000 - 1 000 km Submarine communication
Ultra low frequency ULF 300 Hz - 3 kHz 1 000 - 100 km Submarine communication, Communication within mines
Very low frequency VLF 3 - 30 kHz 100 - 10 km Navigation, time signals, submarine communication, wireless heart rate monitors, geophysics
Low frequency LF 30 - 300 kHz 10 - 1 km Navigation, time signals, AM longwave broadcasting (Europe and parts of Asia), RFID, amateur radio
Medium frequency MF 300 kHz - 3 MHz 1 km - 100 m AM medium-wave broadcasts, amateur radio, avalanche beacons
High frequency HF 3 - 30 MHz 100 m - 10 m Shortwave broadcasts, citizens' band radio, amateur radio and over-the-horizon aviation communications, RFID, Over-the-horizon radar, Automatic link establishment (ALE) / Near Vertical Incidence Skywave (NVIS) radio communications, Marine and mobile radio telephony
Very high frequency VHF 30 - 300 MHz 10 - 1 m FM, television broadcasts and line-of-sight ground-to-aircraft and aircraft-to-aircraft communications. Land Mobile and Maritime Mobile communications, amateur radio, weather radio
Ultra high frequency UHF 300 MHz - 3 GHz 1 m - 100 mm Television broadcasts, microwave ovens, microwave devices/communications, mobile phones, wireless LAN, Bluetooth, ZigBee, GPS and two-way radios such as Land Mobile, FRS and GMRS radios, amateur radio
Super high frequency SHF 3 - 30 GHz 100 - 10 mm Microwave devices/communications, wireless LAN, most modern radars, communications satellites, satellite television broadcasting, DBS, amateur radio
Extremely high frequency EHF 30 - 300 GHz 10 - 1 mm High-frequency microwave radio relay, microwave remote sensing, amateur radio, directed-energy weapon, millimeter wave scanner
Terahertz or Tremendously high frequency THz or THF 300 GHz - 3 THz 1 - 0.1 mm Terahertz imaging, ultrafast molecular dynamics, condensed-matter physics, terahertz time-domain spectroscopy, terahertz computing/communications, sub-mm remote sensing, amateur radio