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, transferred (7/9/2014) to NASA's Ames Research Center in California, where he retired in December, 2016. Dr. Hathaway's new email address is dave.hathaway @ comcast.net.

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 2016/10/06-- For David Hathaway's updates, this link will take you off this site.

Sunspot Cycle Predictions - Updated 2016/10/06 -- For David Hathaway's updates, this link will take you off this site.

RGO/USAF/NOAA Sunspot Database - Updated 2016/10/06 -- For David Hathaway's updates, this link will take you off this site.

Papers -  Updated 2016/12/12 (Falconer et al., 2017)

Papers -  Updated 2015/08/07 (Tiwari et al., 2015 and Tiwari et al., 2014)

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)

Media