15.3 Radio Practicals
215
Analysis and Write-Up
Plot the 15 min count against time. The curve should not be flat. Discuss what you
think this means and the physical process that could cause this. What do you think
the implication of the radiant on the completeness of your detections is and how
might it be improved? What are your sources of error and how significant do you
think these are?
Write up your report in a standard format including your plot and data.
15.3.3 Radio Emission from Jupiter
In 1955, a burst of radio emission was detected from Jupiter at 22 MHz, the first planet
to be detected in the radio spectrum. Part of this emission is synchrotron radiation
from particles trapped in Jupiter’s rather powerful magnetic field. This component
is at 178–5,000 MHz.
A second radio component at 3.5–39.5 MHz was seen that appears to be strongly
related to the orbit of Jupiter’s inner moon, Io. It is thought that Io and Jupiter are
linked by a flux tube, a series of magnetic lines. Electrons spiral down the tube,
emitting radio waves in the process. The spot at which the electrons descend into
Jupiter’s atmosphere has even been detected from Earth. Figure 15.5 illustrates this
interaction.
NASA has developed RadioJove, a school project designed to introduce the public
to radio astronomy.
1 The radioJove project includes a receiver kit, software, and a
simple antenna. This should be suitable for detecting radio emission from Jupiter.
However, in order to get a higher signal-to-noise ratio, it might be worth investing
in a suitable Yagi, a tracking mount, and an off-the-shelf receiver.
However, independent of the kit you have access to, as long as you have a setup
able to receive decimetre emission from Jupiter, you should be able to complete this
practical.
Aims
Using a simple radio telescope and receiver, you will observing the radio emission
from Jupiter and interpret the variation in signal strength.
Observations
You need to observe Jupiter for a number of days (or nights) in order to get a complete
understanding. If you have only a loop antenna, then observing during daylight may
1 The RadioJove project can be found at http://radiojove.gsfc.nasa.gov/.
215
Analysis and Write-Up
Plot the 15 min count against time. The curve should not be flat. Discuss what you
think this means and the physical process that could cause this. What do you think
the implication of the radiant on the completeness of your detections is and how
might it be improved? What are your sources of error and how significant do you
think these are?
Write up your report in a standard format including your plot and data.
15.3.3 Radio Emission from Jupiter
In 1955, a burst of radio emission was detected from Jupiter at 22 MHz, the first planet
to be detected in the radio spectrum. Part of this emission is synchrotron radiation
from particles trapped in Jupiter’s rather powerful magnetic field. This component
is at 178–5,000 MHz.
A second radio component at 3.5–39.5 MHz was seen that appears to be strongly
related to the orbit of Jupiter’s inner moon, Io. It is thought that Io and Jupiter are
linked by a flux tube, a series of magnetic lines. Electrons spiral down the tube,
emitting radio waves in the process. The spot at which the electrons descend into
Jupiter’s atmosphere has even been detected from Earth. Figure 15.5 illustrates this
interaction.
NASA has developed RadioJove, a school project designed to introduce the public
to radio astronomy.
1 The radioJove project includes a receiver kit, software, and a
simple antenna. This should be suitable for detecting radio emission from Jupiter.
However, in order to get a higher signal-to-noise ratio, it might be worth investing
in a suitable Yagi, a tracking mount, and an off-the-shelf receiver.
However, independent of the kit you have access to, as long as you have a setup
able to receive decimetre emission from Jupiter, you should be able to complete this
practical.
Aims
Using a simple radio telescope and receiver, you will observing the radio emission
from Jupiter and interpret the variation in signal strength.
Observations
You need to observe Jupiter for a number of days (or nights) in order to get a complete
understanding. If you have only a loop antenna, then observing during daylight may
1 The RadioJove project can be found at http://radiojove.gsfc.nasa.gov/.