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Animation (QT, 126K)

Space Weather

Space weather happens with a solar storm from the Sun travels through space and impacts the Earth’s magnetosphere.  Studying space weather is important to our national economy because solar storms can affect the advanced technology we have become so dependent upon in our everyday lives. Energy and radiation from solar flares and coronal mass ejections can

• Harm astronauts in space
• Damage sensitive electronics on orbiting spacecraft…
• Cause colorful auroras, often seen in the higher latitudes…
• Create blackouts on Earth when they cause surges in power grids.

Understanding the changing Sun and its effects on the solar system, life, and society is the main goal of NASA's Sun-Earth Connection theme. Many NASA missions focus on the Sun and its interactions with Earth. Current missions include SOHO, ACE, IMAGE, SORCE, and Cluster. Future missions include STEREO and Solar Dynamics Observatory.

Check the Current Space Weather.

Space Weather Images

• A solar storm, aurora from space, and aurora on Earth ( GIF, 98K) ( TIF, 5.1M)

  

• Download the Space Weather Interactive poster includes embedded movie links [PDF, 1.8M]. Also available in Spanish [PDF, 3.0M]. Note: Requires Adobe Reader 8
• Download the print version Space Weather poster [PDF, 1.8M]

Click on image to see a full version

Download a PDF version [PDF, 378K]

The changing Sun produces sunspots and solar storms over an 11-year cycle of activity, which is driven by the reversal of its magnetic poles over this time period. Solar storms (coronal mass ejections and flares) occur most often and more powerfully during its period of solar maximum. The next period of solar maximum is due around 2011.

Animation:The Sun in UV changing over 5 years, EIT 195- Large (QT, 5.2M), small (QT, 1.6M)

Solar Storms

There are two kinds of solar storms: coronal mass ejections (CMEs) and solar flares. A flare occurs when magnetic energy builds to a peak near the Sun's surface and explodes. This intense, fast-paced event sends high-energy particles into space. A much larger storm, a CME erupts when magnetic field lines snap, sending billions of tons of particles into space at millions of miles per hour. The particle cloud expands to over 30 million miles by the time it reaches Earth.

• Video Clips and Animations: Overview animation of solar storm and its impact on Earth (QT, 2.7M)
  Extreme close-up of a sunspot in action, Swedish Solar Telescope large (QT, 3.9M), small (QT, 403K)
  A particle blast close-up, EIT 304. large (QT, 2.2M), small (QT, 717K)
  Flares and solar activity from late 2003 storms, EIT 195. large (QT, 10M), small (QT, 2.6M)
  Close-up of a CME blasting off, EIT 195. large (QT, 1.9M), small (QT, 246K)
  A busy week of solar activity, LASCO C2 large (QT, 7.2M), small (QT, 2.7M)
  Weeks of solar activity from late 2003 storms, LASCO C3 large (QT, 7.7M), small (QT, 3.8M)
  A light-bulb shaped CME, LASCO C3. large (QT, 1.6M), small (QT, 640K)
  Solar streaming and CMEs from the Solarmax IMAX film. large (QT, 4.7M), small (QT, 821K)
  Cascades of loops following a flare from TRACE. large (QT, 3.6M), small (QT, 530K)
  Cascades of loops following a flare from TRACE. large (QT, 2.6M), small (QT, 359K)
  

When the particles ejected from the Sun interact with the Earth's own protective magnetic shield, its magnetosphere, the impact can be observed as aurora. Gases in the upper atmosphere become excited and glow. These are most commonly seen near the Earth's polar regions where the magnetic field lines guide the charged energy toward Earth. If viewed from high above Earth, they appear as ovals. Images taken by astronauts in the space shuttles show the depth of aurora. Other impacts from this energy pouring into the Earth's atmosphere, include short-circuiting power grids that cause blackouts, disrupting communications, damaging satellites, and endangering astronauts with radiation.

• Video Clips and Animations: Auroral oval observed from space by IMAGE. large (QT, 2.0M), small (QT, 148K)
  Auroral ovals over the North Pole region from Polar. large (QT, 4.1M), small (QT, 1.7M)
  Aurora in UV over both polar regions from Polar. (QT, 2.4M)
  NASA animation of Earth's magnetosphere shaped by solar wind (QT, 3.4M)

Aurora

Aurora appear from Earth as shimmering, dancing lights in the night sky. Only 100 years ago did scientists discover that the Sun was the source of these mysterious lights. Although green is the most common color, red and yellow hues are also observed. The most powerful displays occur when large clouds of particles from CMEs slam into our magnetosphere, but the constant outpouring of solar particles (called the solar wind) can cause them as well.

• Video Clips and Animations: Clip of aurora from the Solarmax IMAX film. large (QT, 1.6M), small (QT, 409K)

  Links

  Basic Facts about Space Weather
  Space Weather News
  Space Weather Center
  Stanford Solar Center
  Storms from the Sun
  The Sun from SOHO
  Auroral photographs by Jan Curtis