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THE SUN  

Why We Study the Sun  
The Big Questions  
Magnetism - The Key  

SOLAR STRUCTURE  

The Interior  
The Photosphere  
The Chromosphere  
The Transition Region  
The Corona  
The Solar Wind  
The Heliosphere  

SOLAR FEATURES  

Photospheric Features  
Chromospheric Features  
Coronal Features  
Solar Wind Features  

THE SUN IN ACTION  

The Sunspot Cycle  
Solar Flares  
Post Flare Loops  
Coronal Mass Ejections  
Surface and Interior Flows
Helioseismology  

THE MSFC SOLAR GROUP  

The People  
Their Papers  
Their Presentations  

RESEARCH AREAS  

Flare Mechanisms  
3D Magnetic Fields  
The Solar Dynamo  
Solar Cycle Prediction  
Sunspot Database  
Coronal Heating  
Solar Wind Dynamics  

PREVIOUS PROJECTS  

GOES SXI Instrument  
MSFC Magnetograph  
MSSTA  
Orbiting Solar Obs.  
Skylab  
Solar Maximum Mission  
SpaceLab 2  
The Sun in Time (EPO)  
TRACE  
Ulysses  
Yohkoh  

CURRENT PROJECTS  

GONG  
Hinode  
RHESSI  
STEREO  
SDO  
SOHO  

FUTURE PROJECTS  

Solar Probe  
Interstellar Probe  

VIDEOS  

Solar Probe Plus  

 

The Solar Physics Group at NASA's Marshall Space Flight Center was formed in the early 1970's in conjunction with the Apollo Skylab Mission. These pages contain an overview of solar physics itself along with highlights of our own work, our current projects, and possible future missions.

Please note: Dr. David Hathaway, a member of the MSFC solar physics group for 29 years, has transferred (7/9/2014) to NASA's Ames Research Center in California. Dr. Hathaway's email address remains the same.


Sun Facts

Solar radius = 695,990 km = 432,470 mi = 109 Earth radii
Solar mass = 1.989 × 1030 kg = 4.376 × 1030 lb = 333,000 Earth masses
Solar luminosity (energy output of the Sun) = 3.846 × 1033 erg/s

Surface temperature = 5770 K = 9,930° F
Surface density = 2.07 × 10-7 g/cm3 = 1.6 × 10-4 Air density
Surface composition = 70% H, 28% He, 2% (C, N, O, ...) by mass

Central temperature = 15,600,000 K = 28,000,000° F
Central density = 150 g/cm3 = 8 × Gold density
Central composition = 35% H, 63% He, 2% (C, N, O, ...) by mass

Solar age = 4.57 × 109 yr  

New/Updated Pages

The Sunspot Cycle - Updated 2014/06/12
Sunspot Cycle Predictions - Updated 2014/06/12
RGO/USAF/NOAA Sunspot Database - Updated 2014/06/12
Papers -  Updated 2013/12/20 (Upton and Hathaway 2014)
Papers -  Updated 2013/12/20 (Hathaway, Upton, and Colegrove 2013)
Papers -  Updated 2013/05/20 (Hathaway 2013)
Papers -  Updated 2013/01/29 (Cirtain et al. 2013)
Papers -  Updated 2012/12/10 (Rightmire-Upton, Hathaway, and Kosak 2012)
Papers -  Updated 2012/11/02 (Hathaway 2012b)
Papers -  Updated 2012/06/05 (Falconer et al. 2012)
Papers -  Updated 2012/04/02 (Hathaway 2012)
Papers -  Updated 2012/03/2 (Moore, Falconer, and Sterling 2012)
Presentations -  Updated 2011/12/27 (The Solar Dynamo Saga: Chapter 12)
The Solar Interior - Updated 2011/04/04
The Solar Dynamo - Updated 2011/04/04
Papers -  Updated 2012/02/16 (Hathaway 2011)
Papers -  Updated 2011/03/14 (Wilson 2011a)
Papers -  Updated 2011/03/01 (Hathaway and Rightmire 2011)
Papers -  Updated 2011/02/03 (Hathaway et al. 2010)
Papers -  Updated 2011/02/03 (Falconer et al. 2011)
Papers -  Updated 2011/01/20 (Moore et al. 2011)
Papers -  Updated 2010/07/06 (Wilson 2010b)
Papers -  Updated 2010/07/06 (Moore and LaBonte 1980)
Papers -  Updated 2010/07/06 (Moore and Roumeliotis 1992)
Papers -  Updated 2010/03/29 (Hathaway and Rightmire 2010)
Papers -  Updated 2010/03/16 (Hathaway 2010b)
Papers -  Updated 2010/03/16 (Wilson 2010a)
Papers -  Updated 2010/03/02 (Hathaway 2010a)
Web Links
NOAA's Space Weather Prediction Center - Today's Space Weather Updated Every 5-minutes
sdo.gsfc.nasa.gov/data/ - Latest Images from the Solar Dynamics Observatory
National Space Weather Program - The U.S. Government and Space Weather
First Gov Image + NASA Privacy Policy and Important Notices
+ Visit Solar Terrestrial Probes Program
+ Visit Living With a Star Program
NASA Logo Image Author: Dr. David H. Hathaway, david.hathaway @ nasa.gov
Curator: Mitzi Adams, mitzi.adams @ nasa.gov

Last Updated: August 11, 2014