How NASA Is Saving Fuel On Its Outer Solar System Missions

universetoday.com ^ | on January 9, 2015 | Elizabeth Howell

[BenLurkin]

While Saturn is far away from us, scientists have just found a way to make the journey there easier. A new technique pinpointed the position of the ringed gas giant to within just two miles (four kilometers).

It’s an impressive technological feat that will improve spacecraft navigation and also help us better understand the orbits of the outer planets, the Jet Propulsion Laboratory (JPL) said.

It’s remarkable how much there is to learn about Saturn’s position given that the ancients discovered it, and it’s easily visible with the naked eye. That said, the new measurements with the Cassini spacecraft and the Very Long Baseline Array radio telescope array are 50 times more precise than previous measurements with telescopes on the ground.

[Gamecock]

***A new technique pinpointed the position of the ringed gas giant to within just two miles (four kilometers).***

It’s only the 3rd largest object in the Solar System.

[Born to Conserve]

So, how are they doing it? What is the astrometric technique?

I hope this writer finds another profession.

[cicero2k]

One reason Cassini worked out so well is the nuclear fission power supply.

[cripplecreek]

First imaging from New Horizons begins on the 25th of this month. The first pics won’t be great but will get increasingly more detailed as the closest approach nears.

[Verginius Rufus]

Right now Saturn is a morning star. Next Friday morning, Jan. 16th, it will rise about 3 hours before sunrise and will be within 2 degrees of the moon in the sky.

[Verginius Rufus]

Right now Saturn is a morning star. Next Friday morning, Jan. 16th, it will rise about 3 hours before sunrise and will be within 2 degrees of the moon in the sky.

[Larry Lucido]

A new technique pinpointed the position of the ringed gas giant to within just two miles (four kilometers).

It doesn't stay still. How long does it take Saturn to travel two miles in its orbit?

[Balding_Eagle]

Average orbital speed, according to Wikipedia, is 9.69 km/second, which is about 6 miles.

[Larry Lucido]

Thanks. So coordinates of Saturn to within two miles (measured from where, I’m not sure) would useful for about a third of a second.

Maybe that’s what they mean - that it’s possible to determine more or less exactly where Saturn will be at a particular time.

[conservatism_IS_compassion]

It doesn't stay still. How long does it take Saturn to travel two miles in its orbit?

I’m assuming that "Very Long Baseline Array” technology is - or is an offshoot of - what was called “Synthetic Aperture Radar” twenty years ago.

The idea is that - using hi tech methods - you combine multiple radar “pings” from your moving radar into one measurement with the “antenna size” not limited to the size of your physical antenna but derived from past locations of your (satellite, in this case apparently) radar. Works for a moving target, IIRC.