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Laboratory for Atmospheric and Space Physics

Science and Publications

To the left, you can go to a list of peer-review publications and news articles or to any of the MinXSS science nuggets. Below is a brief description of what MinXSS observes and why.



As the closest star to Earth, the Sun holds a unique place in astronomy for the study of stellar properties that cannot be ascertained from the specks of light that we receive from more distant stars. Such studies have lead to an understanding of many aspects of the Sun, including its structure, cycles, and electromagnetism. In addition to the radiation that is constantly emitted, a stream of solar wind flows outward in all directions. This wind is low-density plasma that breezes through interplanetary space, interacting in particular with the magnetic bodies in the solar system, such as the Earth’s magnetosphere. The Sun occasionally spasms, however, causing a localized ripple in the solar wind. These events are known as coronal mass ejections (CMEs). They are often, but not always, associated with rapid, powerful increases in the high-energy electromagnetic emission, known as solar flares. These two types of energetic release are thought to be manifestations of the same pent-up, non-potential energy in the coronal magnetic fields.

Solar eruptive event is a classification encompassing several types of energetic release from the coronal magnetic fields. The longest studied of these, solar flares, were first observed by Carrington and Hodgson in 1859. Despite many decades of study and an ever-increasing number and precision of observations, many questions remain: How is an eruptive event powered? What triggers it? How is the energy distributed before, during, and after an eruption? How does that energy impact the Earth’s atmosphere?

The science objective of the MinXSS CubeSat is to better understand the solar irradiance energy distribution of solar flare soft X-ray (SXR) emission and its impact on Earth’s ionosphere, thermosphere, and mesosphere (ITM). Energy from SXR radiation is deposited mostly in the ionospheric E-region, from ~80 to ~150 km, but the altitude is strongly dependent on the SXR spectrum because of the steep slope and structure of the photoionization cross sections of atmospheric gases in this wavelength range.