One of the favorite topics of our news is about moon landing. So, on this day (on September 20, 1970) the Soviet Union's Luna 16 moon probe landed on the moon.
Scientists have solved a mystery that finds out how long a day lasts on Saturn. So according to a newly published research by NASA’s Cassini mission;”The researchers used waves in the rings to peer into Saturn’s interior, and out popped this long-sought, fundamental characteristic of the planet. And it’s a really solid result,” Cassini Project Scientist Linda Spilker said in a statement. “The rings held the answer.”
At first sight it seemed to be very easy to know how long a day lasts on Saturn but for a long time scientists have been solving the mystery as the planet is a gas giant. So researchers can’t watch steady landmarks through the clouds, as they could with a rocky planet.
Accordingly, the estimations are as follows; between 10 hours, 36 minutes and 10 hours, 48 minutes — not particularly satisfying. Scientists may also typically use the tilt of a planet’s magnetic field to know and measure its day length. [But that didn’t work for Saturn, because the field aligns nearly perfectly with the planet’s rotation axis, stymying their calculations].
The research published on January 19 but the idea was proposed in 1982.
“Particles throughout the rings can’t help but feel these oscillations in the gravity field,” lead author Christopher Mankovich, a graduate student in astronomy at the University of California, Santa Cruz, said in a statement. “At specific locations in the rings, these oscillations catch ring particles at just the right time in their orbits to gradually build up energy, and that energy gets carried away as an observable wave.”
Space.com indicates “Mankovich and his colleagues studied those observable waves and used them to backtrack inward to the planet itself. That’s how the researchers came up with the measurement of 10 hours, 33 minutes and 38 seconds. It’s still not set in stone — the error bars on that calculation stretch between a minute and 52 seconds longer and a minute and 19 seconds shorter. But the new calculation’s range beats a 12-minute window”.
Source: Text; Space.com
Image credit; Space.com
Pits and Hills on the Edge of the Solar System
Cassini Diagnostic Testing Part of Its Radio System
IBEX and TWINS Observe a Solar Storm
Rare Venus Transit of Sun Occurs in June 2012
Dwarf Planet Haumea
Saturn and the Double Star Porrima
The new twin of our solar system
Photos of Earth through rings of Saturn