Astronomy & Space

See ringed planet Saturn at its greatest in July 2019 – Astronomy Now

July 8, 2019 • By

This looping animation reveals the southern horizon as seen from the British Isles on consecutive sidereal days round 12am BST from 14 to 17 July 2019. Therefore the celebs seem stationary and the movement of the Moon, Jupiter and Saturn is extra simply perceived. For scale, the view is about 50 levels broad, or slightly greater than twice the span of an outstretched hand at arm’s size. Be aware: the Moon’s obvious measurement is enlarged thrice for readability. AN graphic: Ade Ashford.

As July opens, any observer in Western Europe with a transparent sky round native midnight can not miss out on the conspicuous ‘star’ that’s Jupiter low within the south. In the event you’re nonetheless up round 1am, have a look a couple of span-and-a-half of an outstretched hand at arm’s size to Jupiter’s left and, at an analogous peak above the horizon you’ll discover one other big of the photo voltaic system – Saturn. By mid-July, Saturn and Jupiter straddle the southern meridian at native midnight, as depicted within the animation above.

Shining at magnitude +0.1, Saturn is twelve occasions fainter than it’s bigger planetary sibling to the suitable, however the ringed planet remains to be brighter than the rest within the constellation of Sagittarius by which it presently resides. In frequent with Jupiter, Saturn at present occupies a area of the ecliptic that struggles to realize a peak altitude of 14 levels within the south for observers within the coronary heart of the UK, however it’s nonetheless worthy of a glance by means of any sized telescope.

A pc simulation of Saturn’s look at 20:37 UT (9:37pm BST) on Tuesday, 9 July 2019 – the planet’s opposition day and the moment that it’s closest to Earth for 2019 at a distance of 9.03 astronomical items (1,351 million kilometres). Saturn is greatest considered from the UK round 1am in early July, discovered barely a span-and-a-half of a fist at arm’s size above the southern horizon. Nevertheless, even at such a low altitude, on nights of regular seeing the planet’s wonderful rings – with the planet’s north pole at present tilted by 24 levels in the direction of our line of sight – are wonderful to behold in any telescope. What’s the smallest telescope in which you’ll understand the Cassini Division, the skinny black line between the planet’s A & B rings? AN graphic by Ade Ashford/Stellarium.

Observing Saturn
With a declination of -22 levels, Saturn is at present greatest seen from the Southern Hemisphere. As considered from Australia, for instance, the ringed planet is nearly overhead when on the meridian. Saturn’s low altitude from the British Isles signifies that getting clear views will likely be difficult in July 2019, however there are methods that you would be able to enhance your possibilities.

All the time give your telescope ample time to chill right down to nighttime temperatures by uncapping the lens or mirror (with the tube horizontal to keep away from dew deciding on the optics) an hour earlier than making observations. Additionally, observe from a grassy location wherever doable, avoiding concrete or asphalt that retains warmth after darkish. And don’t view Saturn over rooftops the place turbulent heat air currents rise.

Attempt to view Saturn inside an hour or so of the time it transits (see our interactive Almanac for native occasions) in order that it’s as excessive as doable above your horizon. Calm, barely misty nights when a high-pressure system sits above us usually present the steadiest planetary views.

Nevertheless, even in effective UK seeing, each Jupiter and Saturn will show atmospheric dispersion (the place the higher and decrease limbs of the planet could seem to have prismatic blue and purple fringing, respectively) attributable to our ambiance performing like a weak lens. You should buy atmospheric dispersion filters to assist counteract this, or just use a yellow/orange filter to minimize the colored fringes.

The facet of Saturn and the orbits of its brightest moons Titan and Rhea round opposition in July 2019. Observers with Newtonian/Dobsonian telescopes ought to rotate this picture by means of 180° to match their eyepiece view, whereas customers of refractors and catadioptrics (Schmidt- and Maksutov-Cassegrains) with a star diagonal must mirror this graphic left-right to copy what they see by means of the eyepiece. AN graphic: Ade Ashford.

Saturn’s vivid moons
The biggest Saturnian moon, 3,200-wile-wide Titan, orbits its father or mother planet each 16 days and is straightforward to identify in telescopes of 5-cm (2-inch) aperture or bigger because it shines at magnitude +8.5. Titan is at elongation, 4¼ ring diameters east of Saturn, on Three and 19 July. Titan could be discovered the identical distance west of the planet on 11 and 27 July.

Saturn’s second-largest moon Rhea with a 4½-day orbit can be simple to identify at magnitude +10. Elongations two ring diameters east of Saturn happen on 2, 11, 20 and 29 July. Rhea could be seen the identical distance west of Saturn on 4, 13, 22 and 31 July.