There’s not much information about the Sun’s magnetic field and with the latest images, it will help scientists to understand the solar surface better.
The latest images of the Sun taken from the GREGOR telescope shows its popcorn-like surface and a magnetic field in high-resolution. The telescope is the largest in Europe and is placed at the Teide Observatory in the Canary Islands. The telescope went through an upgrade recently, which helped it produced the spectacular pictures of the Sun’s surface.
The GREGOR telescope was inaugurated in 2012 and in 2018, the work on its upgrade began. The upgrade involved optics, alignment, instrumentation, mechanical upgrades for vibration reduction, updated control systems, and building enhancements, among other things. With 1.5 m diameter with an optical footprint of 1.44 m, it allows scientists to resolve structures on the Sun as small as 50 km at 400 nm.
There’s not much information about the Sun’s magnetic field and with the latest images, it will help scientists to understand the solar surface better. It will help them to protect the satellites and our planet from solar activities much better. The latest images captured a tiny fraction of the Sun’s gigantic surface which has a diameter of 8,50,000 miles. For example, it was like spotting a small needle on a football pitch clearly from a distance of one kilometre. The telescope also captured a sunspot in high resolution at the wavelength of 430 nm.
One of the drawbacks in the past with GREGOR was that its image quality did not reach the theoretical limit, partly because the risk was taken with untested technologies, such as silicon carbide mirrors, which could not be polished well enough, and partly because of design problems. But that has now be resolved by replacing all-silicon carbide mirrors with mirrors made of Zerodur, which can be polished to the required quality, and by redesigning the AO relay optics.
‘Very risky project’
The 1.5-meter GREGOR solar telescope was built by a German consortium under the leadership of the Leibniz-Institute for Solar Physics (KIS) in Freiburg, Germany. One of the astrophysicists working on the project said that it was very risky because it usually takes years to upgrade something like GREGOR, but the team was able to achieve it in just one year of time.
