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Making Observations

Getting Started

Now that you have built the Radio Jove Receiver and Antenna you want to take some data -- but first -- a few things you should do in preparation:

  1. Checkout Your Antenna and Receiver Together. Take your time and set up everything you plan to use during actual observations. The optimum setup is the antenna, receiver and a computer running SkyPipe signal plotting software. Get an idea of how long it takes to set up and make sure you know where all the cables go. Get comfortable with the many features of SkyPipe.
  2. Listen to Samples of the Galactic Background, Jupiter, the Sun and various forms of interference. Become familiar with what signals will sound like from your Radio Jove Receiver. Is it Jupiter? Is it a station or some type of man-made interference? Is it lightning (static)? Is it the Sun? [Listen to audio samples.]
  3. Decide What to Listen to. The Sun is stronger than Jupiter, and an easier "target". You can observe the Sun best around local noon, whereas Jupiter observations are made at night (when the earth's ionosphere is more transparent).
  4. Pick the optimum antenna configuration. For the Sun you can probably use a single dipole at 10 ft. For Jupiter you will need to use the dual dipole array . the height will depend upon your latitude (see the antenna manual for details).
  5. Find a Good Site for Your Antenna.One of the most important keys to success is having a good radio-quiet listening site. Generally the best sites are removed from nearby overhead power lines -- arcing insulators have driven some radio astronomers to stamp collecting. If you hear a snarling buzzing sound coming from your speaker, and you can't tune it out, then it is most likely power line buzz. Automobile ignition systems can cause interfering pulses of radio noise so its best to locate away from busy roads. Computer labs and many other types of electronic devices including fluorescent lights, aquarium heaters, electric fences and electric blanket thermostats can cause interference. Some observers travel to a remote site with their antenna in a portable configuration. Others are able to erect their antenna more or less permanently in a back yard or corner of an athletic field.
  6. Pick a Power Source. If you can set up near a source of 115 volt power then you can use a regulated power supply to run the Jove receiver. If you are operating portable then a 12 volt lantern battery is recommended. Check the technical FAQ for more details.
  7. Signals are Strongest when Jupiter or the Sun are in the Beam of Your Jove Antenna. Use the Radio Jupiter Pro SkyMap feature to visualize your antenna pattern in the sky. View the paths of Jupiter and the Sun as they cross the sky, and determine when they are in your antenna beam. The Jove antenna is most effective for a couple of hours before and after transit when object is at its highest position in the sky.
  8. Observe Safely. Never operate with lightning nearby -- always disconnect your antenna when it's not in use. Mark antenna cables and guy wires with bright tape so no one trips over them.

OBSERVING

The Galactic Background

Relativistic electrons spiraling in the galactic magnetic field generate radio noise that is easily detected using the Jove radio telescope. Anytime you listen with your Jove receiver you will hear the galactic background noise. As the earth turns, your antenna will sweep across the galaxy. A 24-hour record of the galactic background noise will show a gradual variation in intensity (you can see a good example of a 24-hour galactic background record here). Twenty-four hour records also demonstrate that during the daytime many stations are present and late at night few stations are received when the earth's ionosphere becomes transparent.

Observing the Sun

  1. Keep Tabs on Sunspot Activity. Solar bursts are stronger than but not as predictable as Jupiter radio noise storms. They are likely to occur when there are sunspots on the visible face of the Sun. Check out solar conditions here. Another good source of information is the Jovetalk listserve. When solar bursts are detected by Jove team members there is usually a lot of traffic on the RJ observers' mailing list.
  2. Learn to Recognize Solar Bursts. Individual solar bursts usually last for about half a minute. Often there is a rapid onset in signal strength followed by a slow decay. The resulting record on SkyPipe looks like a shark fin. The Jove archive contains many SkyPipe records of solar bursts.
  3. Tune the Receiver between Stations. During the daytime the ionosphere is not as transparent as at night and signals from distant stations are often heard. You should tune between stations to a nice quiet frequency when monitoring for solar bursts.
  4. Recording Audio. It always helps to have an audio record when you are trying to identify solar (or Jupiter) signals. We used to use cassette tape recorders but there are none currently sold that are suitable and affordable (you must be able to turn off the automatic level control ALC circuit). The best bet is to use the Pro version of SkyPipe which contains a recording utility. Recording audio on a computer eats memory pretty quickly. Fortunately memory is much more affordable than it used to be.
  5. Join other Observers on the Internet. Many Jove observers are streaming Radio-SkyPipe data. Observatories in Florida and Hawaii are sending out Radio-SkyPipe as well as audio streams and radio spectrograph data in real time. You can be part of all the action as a Radio-SkyPipe client, and even serve your own data out to others. Join the Radio-SkyPipe chat and if there is a Coordinated Observing Telecon you can join in via telephone.

Observing Jupiter

  1. Predict when Jupiter will be active. Jupiter radio noise storms sometimes last for as long as a couple of hours. Storm occurrence is related to which longitude of Jupiter is facing the Earth, as well as the location of the moon Io in its orbit around Jupiter. The Radio Jupiter Pro software calculates all of these factors for you and predicts when Jupiter storms are likely to occur. Using this software will give you the best understanding of the likelihood of a storm occurring. You can also find storm predictions for several time zones on the Jove website. Remember however, even with the best predictions, sometimes Jupiter simply does not perform. Patience is a real virtue -- it may take a few tries before you catch a good storm.
  2. Learn to Recognize Jupiter Bursts. There are two types of Jupiter bursts. S-bursts sound like pebbles on a tin roof . sometimes occurring at rates of dozens of bursts per second. L-bursts sound like ocean waves breaking up on a beach. Often you will hear activity that is a mix of L- and S-bursts. Listen to samples of S- and L- bursts here. The Jove archive contains many SkyPipe records of Jupiter bursts.
  3. Tune the Receiver between Stations. Even at night you may hear signals from distant stations. You should tune between stations to a nice quiet frequency when monitoring for Jupiter bursts. If you hear what you think is Jupiter then rotate the tuning knob slightly. If it is a station the signal should disappear as you tune. Jupiter signals are broad . they cover a wide range of frequencies so if you tune the receiver slightly the signals should still be audible.
  4. Recording Audio. It always helps to have an audio record when you are trying to identify Jupiter (or solar) signals. We used to use cassette tape recorders but there are none currently sold that are suitable and affordable (you must be able to turn off the automatic level control ALC circuit). The best bet is to use the Pro version of Radio-SkyPipe which contains a recording utility. Recording audio on a computer eats memory pretty quickly. Fortunately memory is much more affordable than it used to be.
  5. Join other Observers on the Internet. Many Jove observers are streaming Radio-SkyPipe data. Observatories in Florida and Hawaii are sending out Radio-SkyPipe as well as audio streams and radio spectrograph data in real time. You can be part of all the action as a Radio-SkyPipe client, and even serve your own data out to others. Join the Radio-SkyPipe chat and if there is a Coordinated Observing Telecon you can join in via telephone.

PREDICTION TABLES

IS YOUR TARGET IN THE BEAM?

Whether you are observing Jupiter or the Sun it is important that your "target" be in the antenna beam while you are observing. Radio-Jupiter Pro generates a real-time display showing the location of both the Sun and Jupiter in the sky and indicates when these sources are within the beam of your Jove antenna. It is particularly important that Jupiter be in the beam in order to realize the maximum antenna gain. Solar observations are best made during about a 4-hour window centered on local noon. Sometimes bursts will be strong enough to be detected when the Sun has moved well outside the antenna beam.

DON'T FORGET THAT CHECKLIST

Solar observations can be pretty routine once you get started. Jupiter observations can be a bit more complicated, particularly if you are making observations from a remote field site. There are lots of details to remember and you may wish to use checklist #1 to help get organized. In addition, checklist #2 is useful for remote operations.

INTERNET RESOURCES

Professional radio observatories in Florida and Hawaii participate in Radio Jove by streaming audio and Radio-SkyPipe data over the Internet. Individual observers also stream their Radio-SkyPipe data so you can view signals being received by monitoring stations around the globe. Link here for access to Florida and Hawaii real time data. You are also welcome to view our extensive data archive.

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