Featured Research

from universities, journals, and other organizations

Ulysses Spacecraft Flies Over Sun's North Pole

Date:
January 24, 2008
Source:
NASA/Jet Propulsion Laboratory
Summary:
The Ulysses spacecraft today is making a rare flyby of the sun's north pole. Unlike any other spacecraft, Ulysses is able to sample winds at the sun's poles, which are difficult to study from Earth. Ulysses has flown over the sun's poles three times before, in 1994-95, 2000-01 and 2007. Last week, solar physicists announced the first indications of a new solar cycle. Visiting the pole at this time may lead to new insights about solar activity.

Artist concept of Ulysses making a north polar pass.
Credit: NASA/JPL

The Ulysses spacecraft today is making a rare flyby of the sun's north pole. Unlike any other spacecraft, Ulysses is able to sample winds at the sun's poles, which are difficult to study from Earth.

Related Articles


Ulysses has flown over the sun's poles three times before, in 1994-95, 2000-01 and 2007. Last week, solar physicists announced the first indications of a new solar cycle. Visiting the pole at this time may lead to new insights about solar activity.

"This is a wonderful opportunity to examine the sun's north pole within a transition of cycles," said Arik Posner, Ulysses program scientist at NASA Headquarters in Washington. "We've never done this before."

Many researchers believe the sun's poles are central to the 11-year ebb and flow of solar activity. When sunspots break up, their decaying magnetic fields are carried poleward by vast currents of plasma. This makes the poles a sort of graveyard for sunspots. Old magnetic fields sink beneath the polar surface 200,000 kilometers deep (about 124,000 miles), all the way down to the sun's inner magnetic dynamo, which generates the solar magnetic field. There, dynamo action amplifies the fields for use in future solar cycles.

"Just as Earth's poles are crucial to studies of terrestrial climate change, the sun's poles may be crucial to studies of the solar cycle," said Ed Smith, Ulysses project scientist at NASA's Jet Propulsion Laboratory, Pasadena, Calif.

Each previous flyby revealed something interesting and mysterious. One puzzle has been the temperature of the sun's poles. In the previous solar cycle, the magnetic north pole was about 80,000 degrees Fahrenheit (more than 44,000 degrees Celsius), or 8 percent cooler than the south. The current flyby may help solve this puzzle because it comes less than a year after a similar south pole flyby in Feb. 2007. Mission scientists will be able to compare temperature measurements, north versus south, with hardly any gap between them.

Ulysses also discovered the sun's high-speed polar wind. At the sun's poles, the magnetic field opens up and allows solar atmosphere to stream out at a million miles per hour. By flying around the sun, covering all latitudes in a way that no other spacecraft can, Ulysses has been able to monitor this polar wind throughout the solar cycle and has found that it is acting a bit odd.

"Twelve years ago, just before the previous 'sea change' between solar cycles, the polar wind spilled down almost all the way to the sun's equator. But this time it is not. The polar wind is bottled up, confined to latitudes above 45 degrees, " said Posner.

Launched in Oct. 1990 from the space shuttle Discovery, Ulysses is a joint mission of NASA and the European Space Agency.


Story Source:

The above story is based on materials provided by NASA/Jet Propulsion Laboratory. Note: Materials may be edited for content and length.


Cite This Page:

NASA/Jet Propulsion Laboratory. "Ulysses Spacecraft Flies Over Sun's North Pole." ScienceDaily. ScienceDaily, 24 January 2008. <www.sciencedaily.com/releases/2008/01/080123182720.htm>.
NASA/Jet Propulsion Laboratory. (2008, January 24). Ulysses Spacecraft Flies Over Sun's North Pole. ScienceDaily. Retrieved April 21, 2015 from www.sciencedaily.com/releases/2008/01/080123182720.htm
NASA/Jet Propulsion Laboratory. "Ulysses Spacecraft Flies Over Sun's North Pole." ScienceDaily. www.sciencedaily.com/releases/2008/01/080123182720.htm (accessed April 21, 2015).

Share This


More From ScienceDaily



More Space & Time News

Tuesday, April 21, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Hubble Marks 25th Birthday as Successor Readies for Launch

Hubble Marks 25th Birthday as Successor Readies for Launch

AFP (Apr. 20, 2015) — With the Hubble Space Telescope celebrating its 25th anniversary on April 24, 2015, AFPTV takes a look at Hubble&apos;s control room and gets a sneak peek inside the space center assembling the James Webb Telescope - Hubble&apos;s successor. Duration: 02:52 Video provided by AFP
Powered by NewsLook.com
Rocket Science: Building And Testing The Space Launch System

Rocket Science: Building And Testing The Space Launch System

Newsy (Apr. 19, 2015) — NASA&apos;s new rocket system will eventually be the most powerful ever built by man, but there are a lot of moving parts to test first. Video provided by Newsy
Powered by NewsLook.com
2015 NASA Rover Challenge Underway in Alabama

2015 NASA Rover Challenge Underway in Alabama

Reuters - Light News Video Online (Apr. 19, 2015) — Teams face an uphill battle for fastest rover in this year&apos;s NASA Human Exploration Rover Challenge in Alabama. Julie Noce reports. Video provided by Reuters
Powered by NewsLook.com
International Space Station Captures SpaceX Dragon Spacecraft

International Space Station Captures SpaceX Dragon Spacecraft

Reuters - News Video Online (Apr. 17, 2015) — SpaceX&apos;s Dragon spacecraft reaches the International Space Station and is successfully captured by the station&apos;s robotic arm. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins