Browsing Tag


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.

Astronomy & Space

See dwarf planet Ceres at its greatest for 2019 – Astronomy Now

May 29, 2019 • By

Ceres, the brightest and closest dwarf planet to Earth, reaches opposition at 12am BST on 29 Might. Additionally the biggest of the minor planets between the orbits of Mars and Jupiter, Ceres is a straightforward binocular object attaining magnitude +7 in early June amid the celebs of Scorpius, the place it might be discovered some 18 levels above the southern horizon at 1am BST within the UK, or by 10:30pm BST on the finish of June. Ceres lies about 9 levels (or two 10×50 binocular fields of view) north of first-magnitude Antares, the brightest star in Scorpius. This illustration exhibits subject stars to magnitude +7.5. Click on the graphic for a PDF finder chart appropriate for printing. AN graphic by Ade Ashford.

On Sunday, 26 Might at 21:17 UT, 1 Ceres, the closest and brightest of the dwarf planets and the biggest minor planet contained in the orbit of Neptune, handed closest to Earth for this yr. At this instantaneous, Ceres was 1.7513 astronomical models, or 262 million kilometres (162.8 million miles) from our planet.

Ceres presently lies within the constellation of Ophiuchus, the Serpent Bearer, however the dwarf planet’s westerly movement relative to the celebs carries it into Scorpius on 29 Might the place it resides till 22 June.

This artist’s impression is predicated on an in depth map of the floor compiled from photos taken by NASA’s Daybreak spacecraft in orbit round dwarf planet 1 Ceres. Some 946 kilometres (588 miles) in diameter, Ceres orbits the Solar between Mars and Jupiter as soon as each 4.6 years. It was found by Giuseppe Piazzi in Sicily on 1 January 1801. As seen from Earth, nevertheless, the angular measurement of 1 Ceres by no means exceeds 0.9 arcseconds, so it should seem starlike in a typical yard telescope. Picture credit score: ESO/L.Calçada/NASA/JPL-Caltech/UCLA/MPS/DLR/IDA/Steve Albers/N. Risinger (

Ceres reaches opposition near 12am BST on 29 Might and shines at its peak magnitude of +7.Zero for 2019, fading to +7.Eight by the tip of June, therefore it’s a cushty binocular or small telescope goal — if you recognize precisely the place to look. Click on right here for a printable PDF model of the finder chart on the prime of the web page.

As seen from the UK, Ceres is at present highest within the sky near 1am BST, or by 10:30pm BST on the finish of June, when the dwarf planet is simply 18 levels excessive within the south as seen from the centre of the British Isles.

Ceres can be occulted (hidden) by the Moon on 15 June as seen from Russia (central and east), Kazakhstan (northeast), China (north and east) and Japan.

Astronomy & Space

Mars Helicopter reveals it has ‘right stuff’ for crimson planet – Astronomy Now

April 1, 2019 • By

Because the Wright brothers first took to the skies of Kill Satan Hills, North Carolina, 17 December 1903, first flights have been vital milestones within the lifetime of any car designed for air journey. In spite of everything, it’s one factor to design an plane and make it fly on paper – or laptop. It’s fairly one other to place all of the items collectively and watch them get off the bottom.

In late January 2019, all of the items making up the flight mannequin (precise car going to the Crimson Planet) of NASA’s Mars Helicopter had been put to the check.

Weighing in at not more than four kilos (1.eight kilograms), the helicopter is a know-how demonstration undertaking at present going by the rigorous verification course of certifying it for Mars.

Nearly all of the testing the flight mannequin goes by needed to do with demonstrating the way it can function on Mars, together with the way it performs at Mars-like temperatures. Can the helicopter survive – and performance – in chilly temperatures, together with nights with temperatures as little as minus 130 levels Fahrenheit (minus 90 levels Celsius)?

All this testing is geared in direction of February 2021, when the helicopter will attain the floor of the Crimson Planet, firmly nestled underneath the stomach of the Mars 2020 rover. A couple of months later, will probably be deployed and check flights (as much as 90 seconds lengthy) will start – the primary from the floor of one other world.

“Gearing up for that first flight on Mars, we have logged over 75 minutes of flying time with an engineering model, which was a close approximation of our helicopter,” stated MiMi Aung, undertaking supervisor for the Mars Helicopter at NASA’s Jet Propulsion Laboratory in Pasadena, California. “But this recent test of the flight model was the real deal. This is our helicopter bound for Mars. We needed to see that it worked as advertised.”

Whereas flying helicopters is commonplace right here on Earth, flying lots of of tens of millions of miles (kilometres) away within the skinny Martian ambiance is one thing else solely. And creating the proper circumstances for testing right here on Earth presents its personal set of challenges.

NASA engineers examined the Mars Helicopter in a big vacuum chamber that simulated the martian surroundings. Picture: Picture: NASA

“The Martian atmosphere is only about one percent the density of Earth’s,” stated Aung. “Our test flights could have similar atmospheric density here on Earth – if you put your airfield 100,000 feet (30,480 meters) up. So you can’t go somewhere and find that. You have to make it.”

Aung and her Mars Helicopter crew did simply that in JPL’s House Simulator, a 25-foot-wide (7.62-meter-wide) vacuum chamber. First, the crew created a vacuum that sucks out all of the nitrogen, oxygen and different gases from the air contained in the mammoth cylinder. Of their place the crew injected carbon dioxide, the chief ingredient of Mars’ ambiance.

“Getting our helicopter into an extremely thin atmosphere is only part of the challenge,” stated Teddy Tzanetos, check conductor for the Mars Helicopter at JPL. “To truly simulate flying on Mars we have to take away two-thirds of Earth’s gravity, because Mars’ gravity is that much weaker.”

The crew completed this with a gravity offload system – a motorised lanyard connected to the highest of the helicopter to supply an uninterrupted tug equal to two-thirds of Earth’s gravity. Whereas the crew was understandably involved with how the helicopter would fare on its first flight, they had been equally involved with how the gravity offload system would carry out.

“The gravity offload system performed perfectly, just like our helicopter,” stated Tzanetos. “We only required a 2-inch (5-centimetre) hover to obtain all the data sets needed to confirm that our Mars helicopter flies autonomously as designed in a thin Mars-like atmosphere; there was no need to go higher. It was a heck of a first flight.”

The Mars Helicopter’s first flight was adopted up by a second within the vacuum chamber the next day. Logging a grand complete of 1 minute of flight time at an altitude of two inches (5 centimetres), greater than 1,500 particular person items of carbon fiber, flight-grade aluminium, silicon, copper, foil and foam have confirmed that they will work collectively as a cohesive unit.

“The next time we fly, we fly on Mars,” stated Aung. “Watching our helicopter go through its paces in the chamber, I couldn’t help but think about the historic vehicles that have been in there in the past. The chamber hosted missions from the Ranger Moon probes to the Voyagers to Cassini, and every Mars rover ever flown. To see our helicopter in there reminded me we are on our way to making a little chunk of space history as well.”