QUAOAR - SCIENCE AND TECHNOLOGY
News: There’s
a ring around this dwarf planet. It shouldn’t be there
What's in the news?
● Astronomers
have found a ring around a dwarf planet, located in the Kuiper Belt at the
solar system’s edge, called Quaoar, according to a new study.
Key takeaways:
● The
ring, however, is positioned much further away from the planet than is usual
and defies theoretical explanations.
● Astronomers
believe the new study points to the possibility of discovering more rings
around smaller planets like Quaoar in the outer solar system, which might
expand our understanding of planetary ring systems.
Quaoar:
● The
dwarf planet, which is about half the
size of Pluto and orbits beyond Neptune, is too distant and the ring too
narrow to be seen directly.
Rings and Roche Limit:
● The
observations, by a powerful telescope on La
Palma, reveal the ring to be much further away from the planet.
● The
ring was outside the theoretical maximum for where a ring can survive according
to classical theory.
● The
ring is located at a distance of more than seven planetary radii, twice as far
out as what was previously thought to be the maximum radius, known as the Roche limit.
○ Inside
the Roche limit, the planet exerts strong tidal forces that prevent debris in
the ring amalgamating into a moon.
Dwarf Planets:
Criteria:
● There
are 4 criteria for a celestial body
to be considered as a Dwarf Planet. These criteria’s are set by the
International Astronomical Union (IAU). They criteria’s are
○ The
body orbits around the Sun.
○ It
is not a moon.
○ Has
not cleared the neighbourhood around its orbit (which means it is not the
dominant body in its orbit around the Sun and this is what differentiates a
planet from a dwarf planet).
○ Has
enough mass for its gravity to pull it into a roughly spherical shape.
Five Dwarf Planets:
At
present there are officially five dwarf planets in our Solar System.
● Pluto
is the most famous dwarf planet. It was downgraded from the status of a planet
in 2006.
● Eris
● Makemake
● Haumea
and
● Ceres.