Magnetic Field Polarity

This image shows the magnetic field polarity that Ulysses measured while travelling from the South pole to the North pole of the Sun. The measurements have been mapped onto a sphere corresponding to appropriate solar latitudes and longitudes. Blue values represent regions where the magnetic field pointed toward the Sun, red where it pointed away. The North and South pole switch magnetic direction or polarity every 11 years. This reversal follows the sun spot cycle and is thought to be due to dynamo processes occuring in the solar interior. Green lines represent the boundaries between the two hemispheres. Agreement between actual measurements and predicted models is good, though some discrepancies exist. Work is ongoing on this topic.

Shop Windows to the Universe Science Store!

Our online store includes a wide range of Nature's Own fossil specimens, as well as a mineral and fossil collection perfect for the classroom.

Windows to the Universe Community

News

Opportunities

You might also be interested in:

Cool It! Game

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

Hubble Space Telescope

The Hubble Space Telescope (HST) was one of the most important exploration tools of the past two decades, and will continue to serve as a great resource well into the new millennium. The HST found numerous...more

Apollo 11

Driven by a recent surge in space research, the Apollo program hoped to add to the accomplishments of the Lunar Orbiter and Surveyor missions of the late 1960's. Apollo 11 was the name of the first mission...more

Apollo 12

Apollo 12 was launched on Nov. 14, 1969, surviving a lightning strike which temporarily shut down many systems, and arrived at the Moon three days later. Astronauts Charles Conrad and Alan Bean descended...more

Apollo 15

Apollo 15 marked the start of a new series of missions from the Apollo space program, each capable of exploring more lunar terrain than ever before. Launched on July 26, 1971, Apollo 15 reached the Moon...more

Deep Impact Mission

NASA chose Deep Impact to be part of a special series called the Discovery Program on July 7, 1999. The Discovery program specializes in low-cost, scientific projects. In May 2001, Deep Impact was given...more

Galileo

The Galileo spacecraft was launched on October 19, 1989. Galileo had two parts: an orbiter and a descent probe that parachuted into Jupiter's atmosphere. Galileo's main mission was to explore Jupiter and...more

Lunar Orbiter

During 1966 through 1967, five Lunar Orbiter spacecrafts were launched, with the purpose of mapping the Moon's surface in preparation for the Apollo and Surveyor landings. All five missions were successful....more

Shop Windows to the Universe

We now offer the Cool It! card game in our Science Store. Cool It! is the new card game from UCS that teaches kids about the choices we have when it comes to climate change.

Generous sponsorship of Windows to the Universe is provided by the Hewlett Foundation, the American Geological Institute, the American Geophysical Union, the National Science Foundation, NASA, NCAR, and the CISM and CMMAP projects. NASA CMMAP AGU CISM NCAR Hewlett AGI NSF