A solar eclipse is set to occur on April 8, covering North America. It happens when the Moon obstructs the Sun’s face, creating a temporary darkness akin to twilight. The path of totality, where the Moon’s shadow is darkest, will cross Mexico, Texas, the Midwest, and parts of Canada, ending in Maine. Usually a total solar eclipse graces the earth after every 18 months.
Scientists to study this year’s solar eclipse
Led by Aberystwyth University, an international team of scientists, including members from NASA Goddard Space Flight Center and Caltech, will conduct experiments during the upcoming eclipse near Dallas. Eclipses offer opportunities for valuable scientific research comparable to space missions, with potential to address mysteries surrounding the Sun’s corona.
During a total solar eclipse, the Moon blocks the Sun’s intense light, enabling clear observation of the Sun’s faint corona up to several solar radii. One radius equals half the Sun’s diameter, approximately 696,000km (432,000 miles). Measuring the corona without an eclipse is challenging and typically requires a specialized telescope known as a coronagraph, designed to block direct sunlight to enhance the visibility of fainter corona light. Eclipse observations provide superior clarity compared to space-based coronagraphs.
Sun’s magnetic field structure to be studied
The Coronal Imaging Polarimeter (CIP), named after the Welsh word for “glance”, captures images of the Sun’s corona using polarized light. By measuring polarized light, CIP reveals crucial details about the corona’s density and phenomena like the solar wind. These measurements also aid in understanding the Sun’s magnetic field structure, particularly the extension of large “closed” magnetic loops. CIP’s data helps identify sources of solar wind streams and provides insights into the corona’s magnetic conditions.
The Chils instrument, or coronal high-resolution line spectrometer, gathers high-resolution spectra to detect iron spectral signatures emitted from the corona. It consists of three spectral lines emitted or absorbed within narrow frequency ranges, each indicating temperatures in millions of degrees. By mapping the corona’s temperature, it informs computer models of coronal behavior, aiding in understanding mechanisms like magnetic wave conversion to thermal plasma energy, crucial for replicating temperature variations in models.