The study has been published in the Astrophysical Journal and it looks at simple cases of just one group of Sunspots visible on the Sun’s face.
Sunspots are the dark patches on the Sun’s surface due to the star’s magnetic field. (Image: NASA)
NASA’s new look at Sunspots: For years, Sun has been an object of fascination for scientists. Its study has only been boosted by NASA’s massive fleet of spacecrafts that allow astronomers to take a closer look at the Sun. In fact, one of the spacecrafts is also set to fly through the outer atmosphere of the star. However, it seems that it was this close look that was hampering scientists from linking the Sun to the flares and possibility of life around other stars. Things became clearer when scientists decided to take a step back, the US space agency said in a statement.
Scientists have now conducted a new study where they looked at the Sunspots at a low resolution, as if it were a star “trillions of miles away”. Sunspots are the dark patches on the Sun’s surface due to the star’s magnetic field. This low-resolution distant look at the Sun helped the astronomers understand the stellar activity and also, the conditions for life on planets around other stars.
Japan-based JAXA’s Institute of Space and Astronautical Science scientist and lead author Shin Toriumi said that the team of scientists wanted to take a look at what the Sunspot region would have looked like if they had not been able to resolve it in an image. Therefore, the team used the data from the Sun and treated it as if it came from a distant star. This allowed them to better connect the physics occurring at the Sun and the stars.
NASA study: Why solar flares are important
The statement further added that Sunspots are often forerunners for solar flares. Flares occur when intense energy bursts from the Sun’s surface. Thus, monitoring of the Sunspots becomes important to understand the reason and the manner in which these flares take place. Apart from that, NASA said, a key to understanding whether life can sustain in the solar system of other stars is observing the frequency of flares. NASA further explained how that works, stating that while too many solar flares could destroy entire atmospheres of the planets, making them uninhabitable. On the other hand, a few flares could be very helpful in aiding life on planets as they might help by using simpler building blocks to make complex molecules like DNA and RNA.
NASA studies Sunspots: How did the team go about it?
The team took the high-resolution solar data collected by NASA and Japan’s JAXA and added the light in each image. This helped in converting these high-resolution images into “single data points”. Then, the team strung the subsequent data points together, creating plots of the change in light as the Sunspot passed across the rotating face of the Sun. Scientists call these plots light curves, and they helped the team understand what passing Sunspots would look like if the Sun was several light years away from the Earth.
Goddard Space Flight Centre astrophysicist and study co-author Vladimir Airapetian said that since the Sun is the closest star, the satellites are able to provide images with which signatures can be resolved on the surface 100 miles wide. However, with faraway stars, sometimes the entire surface is shown only in one pixel. With this in mind, the team wanted to create a template using the Sun to make it easier to decode the activity taking place on other stars.
The study has been published in the Astrophysical Journal and it looks at simple cases of just one group of Sunspots visible on the Sun’s face. However, such cases are a rarity, as demonstrated by the only handful of instances where only one group of Sunspot was visible despite over 10 years of data collection by NASA and JAXA. Usually, either multiple groups of Sunspots are visible or there are none at all.
While studying such events, the team found that there were differences in the light curves when they were measured at different wavelengths. The Sun was dimmer when a singular Sunspot appeared at the Sun’s centre. This was done in visible light. On the other hand, when the Sunspot was near the Sun’s edge, it was brighter because of the bright magnetic features found around such Sunspots.
The team also observed the light curves in ultraviolet light and in x-ray, showing the atmosphere above the Sunspots. Scientists found that there was brightening at some wavelengths since the atmospheres above Sunspots were magnetically heated. However, they also discovered, quite unexpectedly, that the heating could dim the light coming from the lower temperature atmosphere. NASA said that these findings might be able to help scientists diagnose the environment of spots on other stars.
Toriumi stated that while the team has only done best-case scenarios with one visible Sunspot so far, they are planning to undertake numerical modeling to get an idea of the impact of multiple Sunspots.