Careful study of our closest star, the Sun, suggests that bundles of twisted magnetic flux tubes extending from subsurface layers may account for the surprising prevalence of x rays from most rather ordinary stars.
The Sun was the first observed x‐ray star. In 1948 rocket‐borne instruments, carried out of the terrestrial atmosphere for only a few minutes at a time, detected solar x rays. Then in April 1960 instruments recorded the first x‐ray photograph of the Sun.
3. G. S. Vaiana, J. P. Cassinelli, G. Fabbiano, R. Giacconi, L. Golub, P. Gorenstein, B. M. Haisch, F. R. Harnden, H. M. Johnson, J. L. Linsky, C. W. Maxson, R. Mewe, R. Rosner, F. Seward, K. Topka, C. Zwaan, Astrophys. J. 245, 163 (1981).https://doi.org/ASJOAB
4. J. L. Linsky, in Solar Phenomena in Stars and Stellar Systems, R. M. Bonnet, A. K. Dupree, eds., Reidel, Boston (1981), p. 99.
5. R. Rosner, L. Golub, G. S. Vaiana, Ann. Rev. Astron. Astrophys. 23, 413 (1985).https://doi.org/ARAAAJ
6. The following are general references: E. N. Parker, Cosmical Magnetic Fields, Clarendon, Oxford (1979); E. R. Priest, Solar Magnetohydrodynamics, Reidel, Boston (1982); P. A. Sturrock, T. E. Holzer, D. M. Mihalas, R. K. Ulrich, eds., Physics of the Sun, Reidel, Boston j (1986).
7. R. Rosner, W. H. Tucker, G. S. Vaiana, Astrophys. J. 220, 643 (1978).https://doi.org/ASJOAB
8. M. Kuperus, J. A. Ionson, D. S. Spicer, Ann. Rev. Astron. Astrophys. 19, 7 (1981).https://doi.org/ARAAAJ
Amid growing investment in planetary-scale climate intervention strategies that alter sunlight reflection, global communities deserve inclusive and accountable oversight of research.
Although motivated by the fundamental exploration of the weirdness of the quantum world, the prizewinning experiments have led to a promising branch of quantum computing technology.
As conventional lithium-ion battery technology approaches its theoretical limits, researchers are studying alternative architectures with solid electrolytes.
November 10, 2025 10:22 AM
This Content Appeared In
Volume 40, Number 7
Get PT in your inbox
PT The Week in Physics
A collection of PT's content from the previous week delivered every Monday.
One email per week
PT New Issue Alert
Be notified about the new issue with links to highlights and the full TOC.
One email per month
PT Webinars & White Papers
The latest webinars, white papers and other informational resources.