SUN'S CORONA

A group of India scientists have recently discovered tiny flashes of radio light emanating from all over the Sun, which they say could help in explaining the long-pending coronal heating problem.

What is Sun’s Corona?

  • The corona is the outermost part of the Sun’s atmosphere. It is the aura of plasma that surrounds the Sun and other stars.
  • The Sun’s corona extends millions of kilometres into outer space and is most easily seen during a total solar eclipse, but it is also observable with a coronagraph.
  • Spectroscopy measurements indicate strong ionization in the corona and a plasma temperature in excess of 1000000 Kelvin much hotter than the surface of the Sun.

Radio lights observed

  • These radio lights or signals result from beams of electrons accelerated in the aftermath of a magnetic explosion on the Sun.
  • While the magnetic explosions are not yet observable, these weak radio flashes are ‘smoking guns’ or the evidence for the same.
  • Hence it brought the researchers closer to explaining the coronal heating problem.

Their significance

  • These observations are the strongest evidence till date that the tiny magnetic explosions originally referred to as ‘nanoflares’ by eminent American solar astrophysicist Eugene Parker.
  • It is the possible phenomena that could be heating up the corona (the aura of plasma that surrounds the sun and other stars).

The Murchison Widefield Array (MWA)

  • The phenomenon of coronal heating has been known for the last 70 years, the availability of cutting edge data from the Murchison Widefield Array (MWA) radio telescope proved to be a game-changer.
  • The MWA is a low-frequency radio telescope, located at the Murchison Radio-astronomy Observatory (MRO) in Western Australia.
  • The MWA has been developed by an international collaboration, including partners from Australia, New Zealand, Japan, China, India, Canada and the United States.

Solving the mystery

  • The strength of the magnetic fields varies a lot from one place on the surface of the Sun to another, by more than a factor of 1,000.
  • But the corona is hot everywhere. So, this heating process has to work all over the corona, even in regions of weak magnetic fields.
  • Until now, the process of how this magnetic energy is deposited in the corona had remained a mystery.

Comments

Post a Comment

Popular posts from this blog

Rise of Economic Nationalism

Image
“Globalization presumes sustained economic growth. Otherwise, the process loses its economic benefits and political support.” Paul Samuelson Context Guess what Corona virus pandemic did that even Soviet union could not? It has shown the world decaying of the capitalist system. Spread of the virus has lead to various forms of lock downs across the globe. This caused multiple problems in economic globalisation to erupt, which made each country look to the protection of its  “own” economy . Now this funda of “own” economy and local over global is what we will focus upon. So stay tuned. Is it the end of Globalization? One of the devastating impacts of Covid-19 will be that nations are going to look even more inwards. Rather than look beyond its borders, nations will focus on their narrowly-defined national interests. Reflecting on the debate on globalization, one may wonder whether the world was entering a new, uncharted territory or if Covid-19 was simply accelerating a push-back agai...
Read more

COVID-19 and its impact on Agriculture

Image
Farmers in India constantly battle against skewed monsoon and erratic rainfall, extreme natural events, interrupted supply chains and rising inflation. Like this was not enough. These troubles now are supplemented this year by the COVID induced lockdowns and the heralding Locusts Attack! God bless our Annadatas! Context The start of the coronavirus  pandemic has coincided with the peak harvesting season . As the markets are locked down, there is a threat to the crop in over 100 lakh hectares in the country. Even among the different segments, the impact varies widely among different regions and among producers and agricultural wage labourers. This impact will reverberate across the larger economy and will linger longer than a few months. Issues surfaced after COVID pandemic In spite of all the measures and in view of continuing restrictions on movements of people and vehicular traffic, concerns have been raised regarding negative implications of COVID19 pandemic on the farm economy....
Read more

Ambarnaya river Oil spill in Russia

Image
Russia has declared a state of emergency after a power plant fuel leak in its Arctic region caused 20,000 tonnes of diesel oil to escape into a local river, turning its surface crimson red. Details of the spillage The Ambarnaya River, into which the oil has been discharged, is part of a network that flows into the environmentally sensitive Arctic Ocean. The state-owned TASS news agency reported that the emergency measures were announced within Russia’s Krasnoyarsk Region, located in the vast and sparsely populated Siberian peninsula. How did the leak happen? The thermoelectric power plant at Norilsk is built on permafrost, which has weakened over the years owing to climate change. The power plant is located near the Region’s Norilsk city, around 3000 km northeast of Moscow. This caused the pillars that supported the plant’s fuel tank to sink. Around 20,000 tonnes of diesel oil was released into the Ambarnaya river, which has since drifted 12 km on its surface. What has Russia done so f...
Read more