VHM/FGM Instrument Page



This image shows the Sun's polarity measured by Ulysses
Click on image for full size and an explanation (64K GIF)
Courtesy of Imperial College
Ulysses has a different orbit than most spacecraft. It got swung past Jupiter into an orbit that takes it past the north and south poles of the Sun. This is the sling shot approach to getting a spacecraft into orbit.

The Sun acts like it has a big magnet in the middle of it. We call this the Sun's magnetic field.

Ulysses is tracking the Sun's magnetic field with an instrument called a magnetometer.It tells how strong the magnetic field is at different times and at different places around the Sun.

Scientists are very excited about the data the magnetometer has collected. They are all looking forward to more new data.

Build your own magnetometer!

Magnetometer measurements taken from 1990-1997

Magnetometer team homepage

Back to Ulysses Instrument Page

VHM/FGM Instrument Page



This image shows the Sun's polarity measured by Ulysses
Click on image for full size and an explanation (64K GIF)
Courtesy of Imperial College
Ulysses has a unique orbit. By going past Jupiter, Ulysses was able to go into an inclined orbit that has never been achieved before (this is the sling shot approach to getting a spacecraft into orbit). From this new type of orbit, Ulysses can track parts of the Sun's magnetic field that have never been tracked.

The magnetometer was included on the Ulysses spacecraft to track the Sun's magnetic field. It uses two different sensors to tell how strong the magnetic field is at different times and at different places around the Sun. The two sensors are called the Vector Helium Magnetometer and the Fluxgate Magnetometer (try saying that 3 times in a row!).

Since being turned on in October 1990, the magnetometers have produced a steady stream of observations. Several disturbances in the magnetic field have been tracked. Scientists look forward to even more findings as Ulysses is in its second pass of the Sun. It is during this second pass that solar activity related to the magnetic field will be at its peak.

Build your own magnetometer!

Magnetometer measurements taken from 1990-1997

Magnetometer team homepage

Back to Ulysses Instrument Page

VHM/FGM Instrument Page



This image shows the Sun's polarity measured by Ulysses
Click on image for full size and an explanation (64K GIF)
Courtesy of Imperial College
Until recently, spacecraft have only been able to measure a limited, two-dimensional section of the heliosphere. This is because spacecraft were confined to stay within the plane of the ecliptic (the plane tilted only 7 degrees from the Sun's equator). Ulysses's unique orbit, achieved with a gravity assist from Jupiter, is 80 degrees inclined to the ecliptic plane which gives the spacecraft a novel vantage point in which to track a 3-dimensional solar heliosphere. One of the fundamental features of the heliosphere is the 3-dimensional structure of the solar magnetic field.

The magnetometer was included on the Ulysses spacecraft to track the spatial and temporal variations of the solar magnetic field. The magnetometer also tracks the polarity of the solar magnetic field. The magnetometer uses two sensors, one a Vector Helium Magnetometer, the other a Fluxgate Magnetometer. Onboard data-processing yields measurements of the magnetic field vector with a time resolution up to 2 vectors/second and a senstivity of .01 - 44,000 nT (nanoTeslas).

Since being turned on in October 1990, the magnetometers have produced a steady stream of observations. Several disturbances in the magnetic field have been tracked, including discontinuities in the field, and shock wave activity. Scientists look forward to even more findings as Ulysses is in its second pass of the Sun. It is during this second pass that solar activity related to the magnetic field will be at its peak.

Teachers, have your students build their own magnetometer!

Magnetometer measurements taken from 1990-1997

Magnetometer team homepage

Back to Ulysses Instrument Page


Last modified October 2, 2000 by the Windows Team

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