Those carrying elegant rings would unquestionably be the talented, popular
students in the class if the planets of our solar system attended school,
and for good cause!
Ring systems are a striking characteristic even in our own world. Since
these rings are difficult to manage, not all planets are fortunate enough to
have them. The majority of them are located near the Roche limit, or a
crucial distance from their host, within which they originate and live under
extremely precise circumstances.
Now, just at the fringe of our solar system, researchers have just
discovered a brand-new ring system! This ring is highly uncommon since it
appears to deviate from the Roche limit, which has caused us to reevaluate
what we presently know about ring systems. It is encircled by the dwarf
planet Quaoar.
recognizing Quaoar's distinctive ring system
Nearly half the size of Pluto, the icy minor planet Quaoar circles the Sun
beyond Neptune. Imagine the difficulties of directly photographing its weak
and small rings as even the most powerful telescopes only view it as a fuzzy
blob due to its size and distance.
Only during a small one-minute window, and even then only indirectly, could
astronomers using the incredibly sensitive high-speed HiPERCAM observe the
rings.
Only when Quaoar, a phenomenon known as stellar occultation, obstructed the
light of distant stars passing in its backdrop was the observation made
feasible. The possibility of a ring system around Quaoar was suggested by
the remarkable starlight dimming that occurred both before and after the
occultation.
The continuous survival of this ring, however, despite its distance from
the parent planet exceeding accepted standards and hypotheses, shocked the
scientists.
In essence, the elaborate rings that surround planets are moons that have
failed to consolidate around smaller objects.
The Roche limit, which established an upper limit for ring systems,
dominated this characteristic of ring systems for the longest period. Beyond
this point, the parent body's tidal forces would drive the ring apart and
cause it to accrete material to create moons.
There are only two additional minor planets known to have ring systems,
Chariklo and Haumea, besides the well-known ring systems of Saturn, Jupiter,
Uranus, and Neptune. With the exception of Chariklo's rings, which have
barely strayed over the line, all of these ringed planets are within the
Roche limit.
Quaoar, a rare renegade, has forced astronomers to reevaluate the
boundaries of ring systems. Its ring is located more than seven planetary
radii away, or around 4023 kilometers.
The scientists determined the greatest radius to be 1770 kilometers, which
is well above the Roche limit and twice as far as what was previously
believed to be the maximum radius.
"Really, it has no place there. We should revisit this restriction to
acquire a deeper understanding of the formation of these satellites, "Dr.
Bruno Morgado, the study's principal author, stated.
Everyone is taught about Saturn's wonderful rings when they are young, so
maybe this new discovery will provide further light on how they came to be,
said Professor Vik Dhillon, a co-author of the study from the Department of
Physics and Astronomy at the University of Sheffield.
For us, this finding serves as a welcome reminder that several more equally
transformative scientific discoveries are still out there. We are just
getting closer to discovering the wonderful treasures buried in space as
more sophisticated telescopes are developed.
