AND total solar eclipse takes place April 8 in North America. These events occur when the Moon passes between the Sun and Earth, completely blocking the Sun’s face. This plunges observers into darkness just like dawn or dusk.
During the upcoming eclipse, the trail of totality, during which observers experience the darkest a part of the Moon’s shadow (umbra), crosses Mexico, arcs northeast through Texas, the Midwest and briefly enters Canada before ending in Maine.
Total solar eclipses occur roughly every 18 months in some place on Earth. The last total solar eclipse to omit the United States occurred on August 21, 2017.
An international team of scientists led by Aberystwyth University will perform experiments with, amongst others: near Dallas, in a place on the trail of wholeness. The team consists of graduate students and researchers from Aberystwyth University, NASA Goddard Space Flight Center in Maryland and Caltech (California Institute of Technology) in Pasadena.
Valuable scientific research will be conducted during eclipses which can be comparable to or higher than what we are able to achieve with space missions. Our experiments may also shed light on a long-standing mystery concerning the outermost a part of the Sun’s atmosphere – its corona.
NASA Science Visualization Studio
The intense light of the Sun is blocked by the Moon during a total solar eclipse. This means we are able to observe Weak solar corona with incredible clarity, from distances very near the Sun, all the way down to a few solar rays. One radius is a distance equal to half the diameter of the Sun, or about 696,000 km (432,000 mi).
Measuring the corona without an eclipse is incredibly difficult. Requires a special telescope called a coronagraph designed to dam direct sunlight. This allows the weaker coronal light to be distinguished. The clarity of eclipse measurements exceeds even that of coronagraphs made in space.
We may observe Corona with a relatively small budget, in comparison with e.g. spacecraft missions. The constant conundrum surrounding corona is statement that it is way warmer than the photosphere (the visible surface of the Sun). As you progress away from a hot object, the ambient temperature should decrease, not increase. How the corona heats as much as such high temperatures is one among the questions we’ll investigate.
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We have two important scientific instruments. The first is Cip (coronal imaging polarimeter). Cip can also be a Welsh word meaning “look” or “quick glance”. The instrument takes photos of the solar corona using a polarizer.
The light we would like to measure from the corona is extremely polarized, which suggests it consists of waves vibrating in a single geometric plane. A polarizer is a filter that permits light of a specific polarization to go through while blocking light of a different polarization.
The Cip images will allow us to measure basic properties of the corona, akin to its density. It may even shed light on phenomena akin to the solar wind. It is a stream of subatomic particles in the shape of plasma – superheated matter – flowing repeatedly outward from the Sun. Cip may help us discover the sources in the solar atmosphere of some solar wind streams.
Direct measurements of the magnetic field in the Sun’s atmosphere are difficult. However, the eclipse data should allow us to review its fine-scale structure and trace the direction of the sector. We will give you the option to see how removed from the Sun magnetic structures called large “closed” magnetic loops extend. This, in turn, will provide us with details about large-scale magnetic conditions in the corona.
NASA/Solar Dynamics Observatory
The second instrument is Chils (High Resolution Coronal Linear Spectrometer). It collects high-resolution spectra in which light is separated into its component colours. Here we’re on the lookout for a particular spectral signature of iron emitted from the corona.
It consists of three spectral lines in which light is emitted or absorbed in a narrow frequency range. Each of them is generated at a different temperature range (thousands and thousands of degrees), so their relative brightness tells us concerning the temperature of the corona in different regions.
Mapping the temperature of the corona provides advanced computer models of its behavior. These models must keep in mind the mechanisms for heating the coronal plasma to such high temperatures. Such mechanisms may include, for instance, the conversion of magnetic waves into thermal plasma energy. If we show that some regions are warmer than others, this will be reproduced in the models.
This 12 months’s eclipse also occurs at a time of increased solar activity, so we could observe a coronal mass ejection (CME). These are huge clouds of magnetized plasma ejected from the Sun’s atmosphere into space. They can affect near-Earth infrastructure, causing problems for key satellites.
Many facets of CMEs are poorly understood, including their early evolution near the Sun. Spectral details about CMEs will give us details about their thermodynamics and their speed and expansion near the Sun.
Our eclipse instruments were recently proposed for a space mission called Moon-assisted solar occultation mission (Mesom). The plan is to orbit the Moon to get more frequent and longer eclipse observations. It is planned as a multi-country British Space Agency mission but led by University College London, the University of Surrey and Aberystwyth University.
We may even have a complicated business 360-degree camera to capture video of the April 8 eclipse and viewing locations. The video is worthwhile for public events where we highlight the work we do and helps generate public interest in our local star, the Sun.
