Featured Research

from universities, journals, and other organizations

Powerful 'Conveyer Belts' Drive Sun's 11-year Cycle, New Evidence Suggests

Date:
June 20, 2003
Source:
NASA/Marshall Space Flight Center
Summary:
NASA and university astronomers have found evidence that the 11-year sunspot cycle is driven in part by a giant conveyor belt-like, circulating current within the Sun.

NASA and university astronomers have found evidence that the 11-year sunspot cycle is driven in part by a giant conveyor belt-like, circulating current within the Sun.

The astronomers, Dr. David Hathaway, Robert Wilson and Ed Reichmann of NASA's Marshall Space Flight Center in Huntsville, Ala., and Dr. Dibyendu Nandy of Montana State University in Bozeman, reported their findings the week of June 16 at the annual meeting of the Solar Physics Division of the American Astronomical Society in Laurel, Md. The results were also published in the May 20 issue of the Astrophysical Journal.

The astronomers made their discovery by reviewing the positions and sizes of all sunspots seen on the Sun since 1874. "The sunspots appear in two bands on either side of the Sun's equator," said Hathaway. "Although the individual sunspots come and go from week-to-week, the central positions of the bands in which they appear drift slowly toward the solar equator over the course of each 11-year sunspot cycle."

Previously, scientists believed this equator-ward drift was a wave-like process involving magnetic forces. However, this new evidence suggests this drift is produced by a giant circulation system in which the compressed gases, 125,000 miles below the Sun's surface, move from the Sun's poles to its equator at about three mph -- a leisurely walking pace. The gases then rise near the equator and turn back toward the poles, traveling in the surface layers where the gas is less compressed -- moving at a faster rate of approximately 20 to 40 mph. Recent progress in theoretical modeling of the sunspot cycle has emphasized the important role of this circulation.

The speed of this circulation system, called a meridional circulation, changes slightly from one sunspot cycle to the next. The circulation is faster in cycles shorter than the average 11-year period and slower in cycles longer than the average period. This is a strong indication that this circulation acts like an internal clock that sets the period of the sunspot cycle.

The circulation also appears to influence the strength of future cycles, as seen in the number and sizes of the sunspots produced, not in the cycle immediately following, but rather in a two-cycle or 22-year time lag. When the flow is fast, it concentrates the magnetic field at the Sun's poles. These stronger fields are then transported downward into the solar interior where they are further compressed and amplified to become the intense magnetic fields that form sunspots years later.

The Sun is now in the declining phase of the current sunspot cycle that peaked in 2000 and 2001. Because the circulation flow was fast during the previous cycle, the astronomers believe the next cycle will be a strong one, peaking in the years 2010 and 2011.


Story Source:

The above story is based on materials provided by NASA/Marshall Space Flight Center. Note: Materials may be edited for content and length.


Cite This Page:

NASA/Marshall Space Flight Center. "Powerful 'Conveyer Belts' Drive Sun's 11-year Cycle, New Evidence Suggests." ScienceDaily. ScienceDaily, 20 June 2003. <www.sciencedaily.com/releases/2003/06/030620080456.htm>.
NASA/Marshall Space Flight Center. (2003, June 20). Powerful 'Conveyer Belts' Drive Sun's 11-year Cycle, New Evidence Suggests. ScienceDaily. Retrieved September 17, 2014 from www.sciencedaily.com/releases/2003/06/030620080456.htm
NASA/Marshall Space Flight Center. "Powerful 'Conveyer Belts' Drive Sun's 11-year Cycle, New Evidence Suggests." ScienceDaily. www.sciencedaily.com/releases/2003/06/030620080456.htm (accessed September 17, 2014).

Share This



More Space & Time News

Wednesday, September 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Boeing, SpaceX to Send Astronauts to Space Station

Boeing, SpaceX to Send Astronauts to Space Station

AFP (Sep. 17, 2014) — NASA selected Boeing and SpaceX on Tuesday to build America's next spacecraft to carry astronauts to the International Space Station (ISS) by 2017, opening the way to a new chapter in human spaceflight. Duration: 01:13 Video provided by AFP
Powered by NewsLook.com
East Coast Treated To Rare Meteor Sighting

East Coast Treated To Rare Meteor Sighting

Newsy (Sep. 16, 2014) — Numerous residents along the East Coast reported seeing a bright meteor flash through the sky Sunday night. Video provided by Newsy
Powered by NewsLook.com
Space Race Pits Bezos Vs Musk

Space Race Pits Bezos Vs Musk

Reuters - Business Video Online (Sep. 16, 2014) — Amazon CEO Jeff Bezos' startup will team up with Boeing and Lockheed to develop rocket engines as Elon Musk races to have his rockets certified. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
NASA Picks Boeing and SpaceX to Ferry Astronauts

NASA Picks Boeing and SpaceX to Ferry Astronauts

AP (Sep. 16, 2014) — NASA is a giant step closer to launching Americans again from U.S. soil. It has announced it has picked Boeing and SpaceX to transport astronauts to the International Space Station in the next few years. (Sept. 16) Video provided by AP
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:
from the past week

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