Why will Saturn’s rings briefly ‘disappear’ from view in 2025?

Why will Saturn’s rings briefly ‘disappear’ from view in 2025?

Context- One of the most spectacular sights in the Solar System is the majestic ringed planet Saturn, which is clearly visible in the evening sky through a telescope. In 2025, however, Saturn’s rings will seemingly disappear from view.

(Credits- Fox News)

It isn’t as if the planet will lose them forever. The rings will just be invisible from Earth and will reappear soon thereafter. The reason for this temporary disappearance has to do with Saturn’s tilt and an optical illusion.

Why will Saturn’s rings be invisible from Earth?

  • Like Earth’s axis of rotation, which is tilted by 23.5 degrees, Saturn’s axis of rotation has a 26.7 degree tilt — its enormous ring system is also tilted to the plane of Saturn’s orbit. As a result, when Saturn revolves around the Sun, it seems to nod up and down when viewed from Earth and the view of its rings also keeps changing.
  • Saturn takes 29.5 years to complete an orbit around the Sun and every 13 to 15 years, the edge of its rings aligns directly with Earth.
  • As the rings are very thin — in most places, just tens of metres thick — at this position, “they reflect very little light, and are very difficult to see, making them essentially invisible,”.
  • In March 2025 — Saturn’s rings will not be visible from Earth because they will be perfectly aligned with our line of sight. The rings will gradually return to view as the planet will continue to revolve around the Sun.

Will Saturn’s rings actually disappear in the future?

  • Yes, they might. According to a 2018 report by the National Aeronautics and Space Administration (NASA), Saturn would probably lose its rings completely in the next 300 million years, or even sooner than that.
  • It will probably happen because the rings are being pulled into the planet by its gravity as a dusty rain of ice particles under the influence of Saturn’s magnetic field, said the report.
  • “We estimate that this ‘ring rain’ drains an amount of water products that could fill an Olympic-sized swimming pool from Saturn’s rings in half an hour,” according to James O’Donoghue of NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
  • The report also added that Saturn, which is four billion years old, got the rings much later in its life since the rings aren’t older than 100 million years.
  • “We are lucky to be around to see Saturn’s ring system, which appears to be in the middle of its lifetime. However, if rings are temporary, perhaps we just missed out on seeing giant ring systems of Jupiter, Uranus and Neptune, which have only thin ringlets today!” O’Donoghue added.

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Source- Indian Express