Some keen-eyed observers have even claimed to see the crescent with the naked eye! However, Venus' brilliance produces considerable glare when seen against a dark sky, so when using optical aid, it is best observed in bright twilight.
When shining at its greatest brilliancy, Venus can cast faint shadows at night, and it can even be glimpsed in daylight given a clear, haze-free sky and provided that the planet is well clear of the Sun. The best way to see Venus in daylight is when it is a 'Morning Star', when it can be continually observed through to sunrise and beyond.
Venus comes closer to the Earth than any other planet - to within 26 million miles 41 million kms. Its brilliance is largely due to the high reflectivity albedo of its clouds, which perpetually obscure the view of the planet's extremely hot surface.
Ephemeris Its greatest brilliance occurs about 5 weeks after greatest Eastern elongation evening apparition and about 5 weeks before greatest Western elongation morning apparition.
In the following list, greatest elongation details are given in brackets in the format "Solar elongation, Constellation". Star map showing the path of Venus through the zodiac constellations during the earlier part of the planet's evening apparition in The latter part of the apparition is shown on a second chart click to see the full-size image, description of the apparition, horizon diagrams showing Venus' position above the horizon after sunset and Moon nearby dates for the period.
History of Telescopic Observation. The phases of Venus were first observed telescopically by Italian astronomer, philosopher and physicist Galileo Galilei in , using one of the world's first telescopes the first telescope is believed to have been made by Dutch spectacle maker Hans Lipperhey around The observation of Venus' Moon-like phases was an important discovery because it provided clear evidence in favour of the 'Copernican' system of planetary orbits - proposed by Polish cleric and astronomer Nicolaus Copernicus in the 16th century - which said that the Sun was at the centre of our Solar System.
In Galileo's time, the 'Ptolemaic' system - which put the Earth at the centre of the Solar System - was the widely held view. Galileo's defence of the Copernican system brought him into conflict with the Roman Catholic Church, and it ultimately led to him being held under house arrest until his death in Iove Jove.
King of the Gods. Apparent Magnitude:. Phaethon "glittering one". Greek god: Zeus. Jupit e r appears bright white and is a very obvious sight in the night sky. Like Venus, it can be seen in twilight, and it always shines brighter than the brightest star in the night sky - Sirius magnitude Viewed from the Earth, Jupiter is seen to move through about one zodiac constellation ca. The four moons are brighter than the typical naked eye limiting magnitude ca.
Sometimes only two or three moons will be seen on a given night - in which case, the remainder are either in front of, or behind, the giant planet. Small telescopes will show Jupiter as a pale white or cream-colour. They will also reveal the planet's two most prominent cloud belts: the North and South Equatorial Belts , and with patience, Jupiter's most famous feature - its Great Red Spot.
Although it is by far the largest of the Solar System planets, Jupiter is not the brightest planet when seen from the Earth - this particular honour goes to Venus. Jupiter is fainter than Venus because of its much greater distance from the Earth. Like Venus, Jupiter can also cast faint shadows at night when it is shining at its brightest and is observed under very dark skies.
Star map showing the path of Jupiter through Scorpius, Ophiuchus, Sagittarius, Capricornus and Aquarius from November to March click for full-size image, description and Moon nearby dates for the current year. Jupiter's four brightest moons were first seen telescopically by Galileo in ; for this reason they are often referred to as the 'Galilean satellites' or simply the 'Galileans'. A year later, the moons were observed independently by German astronomer Simon Marius, who subsequently named them.
Marte ,. God of War. Pyroeis "fiery one". Greek god: Ares. Mars is easily recognised since it has the most distinctive coloration of all the naked eye planets. Although it is popularly called ' The Red Planet ', it rarely appears red to the naked eye; in fact, it varies from pale orange-yellow to orange-red, depending upon its distance from the Earth and therefore, its brightness. The reddish colour is caused by the presence of iron oxide rust on the planet's surface.
Mars' attractive coloration has often given rise to descriptive terms such as "orange spark", "campfire orange", "pumpkin orange" and so on. Occasional global dust storms on Mars, such as those which happened in and , can however make it appear decidedly yellowish. Because of its eccentric orbit, Mars' distance from the Earth varies considerably from one opposition to the next, which typically take place about every 2 years and 7 weeks see Mars oppositions page.
In the opposition of , Mars came closer to the Earth than it had been for almost 60, years. For about six weeks either side of opposition, Mars can clearly be seen in twilight; at its brightest, Mars outshines Sirius the brightest star in the night sky but even at its more distant oppositions it outshines the star Arcturus magnitude Note that because of Mars' eccentric orbit, the dates of its opposition and its closest approach to the Earth can differ by up to two weeks.
When it is on the far side of its orbit from the Earth i. Through a telescope , Mars typically appears amber or salmon-pink in color. It is a difficult planet to observe - despite its relative closeness - since it is only about half the size of the Earth. Under good atmospheric seeing conditions , small telescopes will reveal one or other of its polar caps and some bluish-grey surface markings which often change their appearance with the Martian seasons.
Mars has two asteroid-like moons, Phobos and Deimos. They are too faint to be seen with binoculars and can only be seen with medium and large-sized telescopes around opposition - and even then, only when their orbits carry them well clear of the planet's bright disk.
A device known as an occulting bar can be used to conceal Mars from view in the telescopic eyepiece, allowing the moons to be spotted with greater ease. Star map showing the path of Mars through Aquarius, Pisces, Aries and Taurus from May to March click for full-size image, a detailed description of the apparition and Moon nearby dates for the period.
The first telescopic observation of Mars was by Galileo in He was able to resolve the gibbous phase of the planet, but no surface details. The first definite surface details were observed by Dutch astronomer Christiaan Huygens in ; his drawings show a dark triangular feature, which is now known to be 'Syrtis Major'.
Mars' polar caps were first observed by Giovanni Cassini in When Italian astronomer Giovanni Schiaparelli turned his telescope on Mars in , he saw what he believed to be a series of linear features criss-crossing the planet, which he named 'canali' Italian for 'channels', though it was incorrectly translated into English as 'canals'. He thought they might be artificial structures, built by the Martians to irrigate the planet by transferring water from the polar caps to the warmer, drier regions of the planet.
His observations were supported by other astronomers, the most notable being Percival Lowell founder of Flagstaff Observatory in Arizona but the idea was rejected by numerous others, who were unable to see the features that Schiaparelli had claimed to see. The 'canals on Mars' controversy was finally resolved when the first spacecraft were sent to take close-up pictures of the planet in the s. No canals were found to exist on Mars, and what Schiaparelli had probably seen were the result of telescopic defects or tricks of the eye.
Schiaparelli had also believed that the dark regions on Mars were caused by vegetation growth an idea first suggested by French astronomer E. Liais in The idea seemed credible because the dark areas appeared to expand and retract in synchrony with the Martian seasons. Today we know that these dark regions are simply a colour contrast effect; their apparent spreading and shrinking being the result of seasonal dust storms , which blow light-coloured dust away from the darker-coloured surface.
In , partly inspired by Schiaparelli and Lowell's ideas, English writer H. Wells published his classic novel 'The War of the Worlds', which described a Martian invasion of the Earth as witnessed by a London-based writer see Reference 1. Naval Observatory in Washington, DC in The logic behind their idea seems to have been that, since the Earth had one moon and Jupiter was known to have four moons, Mars must have had an intermediate number, i. However, an alternative explanation may be that the authors drew their inspiration from German astronomer Johannes Kepler, who in had apparently suggested that Mars may have two moons.
All three 'visionaries' were officially recognised following spacecraft missions to the Martian moons in the s - Kepler had a geological ridge on Phobos named after him, whilst Swift and Voltaire each had a crater on Deimos named after them!
Mercurius ,. Messenger of the Gods. Stilbon "shining one". Greek god: Hermes. Mercury is generally more difficult to spot than the other bright planets, mainly because, from the vantage point of the Earth, Mercury never appears very far from the Sun between 17 and 28 degrees away, the variation being due to its highly eccentric orbit. Consequently, on most occasions it can only be seen with the naked-eye when it is low down in twilight, either shortly after sunset or before sunrise. Mercury typically makes three morning appearances and three evening appearances each year, though for any given location on Earth, Mercury will only be well placed for viewing on about half of these occasions because of the length of local twilight and the angle of the ecliptic to the local horizon.
Around greatest elongation in the evening, binoculars will help to locate it - in the general direction of the sunset - around 45 minutes or so after sundown the exact time to start looking depends upon the length of local twilight after which its position should be easily pinpointed with the naked eye.
Likewise, during morning apparitions, the planet should be found in the general direction of sunrise about 45 minutes or so before sunup. Mercury is generally white in colour, though its low altitude angular height above the horizon causes it to take on a somewhat pinkish hue, for the same reason that the Sun appears reddish at sunrise or sunset indeed, both Venus and Jupiter can appear orange-red when they are close to the horizon.
Because Mercury is the closest planet to the Sun and it moves so swiftly, its brightness varies rapidly during any given apparition. Like Venus, Mercury shows phases when seen through a telescope, however Mercury is a less impressive sight because of its smaller apparent size and the much poorer seeing conditions at low altitude.
For the same reason, Mercury appears to scintillate twinkle more readily than the other bright planets. Mercury is easiest to see when it reaches greatest elongation, however it can normally be seen for several days either side of this date. A flat, unobstructed horizon is required to see it. In the following list, details are given in the format "Solar elongation, Constellation, Favourable Viewing Hemisphere".
The constellation in which Mercury is located is rarely visible because of twilight, however it can be used as an aid in determining the direction in which to look for the planet times of local sunrise, sunset and twilight can be obtained from TimeandDate. Mercury can sometimes be found more easily when Venus is nearby; for a list of dates when this occurs through to see here.
Morning Apparition Western Elongation :. Evening Apparition Eastern Elongation :. Star map showing the path of Mercury through Virgo from September to October , covering both evening and morning apparitions of the planet click for the full-size star chart and a description of Mercury's movements, included in an article describing Venus' evening apparition of In , before the invention of the telescope, Polish astronomer Nicolaus Copernicus summarised the difficulties in observing Mercury when he wrote:.
The phases of Mercury were first observed telescopically by another Polish observer - Johannes Hewelcke commonly known as Hevelius - in the first half of the 17th century. The first serious observation of the planet was by English but German-born astronomer and musician Wilhelm William Herschel in the late 18th century. Herschel was, however, unable to detect any of Mercury's surface features. Saturnus ,. God of Agriculture. At opposition:.
Phainon "shining one". Greek god: Cronus or Kronos. Saturn appears pale yellow to the naked eye. Although never appearing as bright as the other naked eye planets, it is nonetheless obvious when its position is known. At its brightest, Saturn outshines all of the stars except Sirius magnitude Saturn's famous ring system can be seen in a small telescope at magnifications above ca.
The rings contribute a great deal to its brightness, and in fact, from the vantage point of the Earth, they are not always on view. About every 15 years, the rings are edgewise-on to the Earth's line-of-sight, at which times they are only seen as a thin line in telescopes - or not at all - and as a result the planet appears much dimmer in the sky.
W hen its rings are fully displayed - at opposite points in its orbit - Saturn shines at its brightest; this last took place in For more details, see the diagram of Saturn's orbit , which includes an animation of its changing ring aspects from to It orbits Saturn once every 16 days, appearing up to four Saturn ring-diameters away from the planet's centre. Of the brighter telescopic moons, Iapetus is the outermost, appearing up to thirteen ring-diameters away from the planet's centre.
Star map showing the path of Saturn through the constellations of the Southern zodiac Libra, Scorpius, Ophiuchus, Sagittarius and Capricornus from November to February click for full-size image, description and Moon nearby dates for the current year. The first telescopic observation of Saturn was by Galileo in , but his telescope was unable to resolve the rings in their true form. Saturn must have been a puzzling sight to Galileo; he saw the planet as three separate parts which, in his own words,"almost touch one another and never move nor change with respect to one another".
Christiaan Huygens, following his telescopic observations of the planet in , correctly described the true nature of the rings when he said "Saturn is surrounded by a thin flat ring not touching it anywhere, which is oblique to the ecliptic". Huygens also discovered Titan that same year. The early astronomers often referred to Saturn's rings as 'ansae' Latin for 'handles' because of their apparent resemblance to the handles of a vase.
Shining like a "star" with a yellow-orange hue, Mars can vary considerably in brightness. It will be visible in the evening from Jan. Coming off a spectacular autumn apparition in , when Mars came within On New Year's Day it resembles the brilliant star Arcturus, both in terms of color and brightness; thus, is at its brightest at the very start of the year.
Positioned against the stars of Pisces, Mars is high in the south-southeast at nightfall and will not set until a. In the weeks and months to come, as Mars pulls farther away from Earth its brightness diminishes. By mid-May it has dropped to the rank of second-magnitude and it is setting before midnight.
When it finally disappears into the sunset fires in late August, it will have receded to million miles million km away. It then goes on a "sabbatical" of sorts, through the balance of the summer and well into the fall.
It finally reappears late in November, low in the east-southeast sky. By New Year's Eve, it will be rising around a. It will be well on its way toward another bright opposition which will take place almost a year later on December 8, On the evening of July 13, Mars will stand very closely below a much brighter Venus. On the evening of July 30, Mars will pass closely above the 1st magnitude star Regulus in Leo.
Jupiter is quite brilliant with a silver-white luster. Evenings from Jan. Through all of , the king of the planets will be situated against the star background of Capricornus the Sea Goat. Brightest in Aug. Jupiter is at opposition to the Sun on August 20, shining at a dazzling magnitude of On the morning of March 5, about a half hour before sunup, Jupiter will appear just to the right of Mercury.
Saturn shines like a yellowish-white "star" of moderate brightness. Its famous rings are only visible in a telescope. They were at their maximum tilt toward Earth in October and are now closing to our line of sight. Iron looks black, but the element takes on a reddish tinge when it has been exposed to oxygen, i. Coming off a spectacular autumn apparition in when Mars came within Positioned against the stars of Pisces, Mars is high in the south-southeast at nightfall and will not set until a.
In the weeks and months to come, as Mars pulls farther away from Earth its brightness diminishes. By mid-May it has dropped to rank of second-magnitude and it is setting before midnight. When it finally disappears into the sunset fires in late August, it will have receded to million miles million km away. It finally reappears late in November, low in the east-southeast sky. It will be well on its way toward another bright opposition which will take place almost a year later on December 8, ,.
Read more about Mars! Jupiter is usually the third brightest object in the night sky, after the Moon and Venus only Mars, our next-door neighbor, is occasionally brighter , and summer is an especially good time to view this bright behemoth. Through all of , the King of the planets will be situated against the star background of Capricornus the Sea Goat.
Brightest in : August 8 to September 2. Jupiter is at opposition to the Sun on August Learn more about Jupiter! Saturn is the sixth planet from the Sun, and the second largest, after Jupiter.
It is one of the five planets visible from Earth using only the naked-eye the others are Mercury, Venus, Mars and Jupiter. The famous rings are only visible in a telescope.
They were at their maximum tilt toward Earth in October and are now closing to our line of sight. All through , Saturn will found within the boundaries of Capricornus the Sea Goat.
Read more about Saturn! Uranus can be glimpsed as a naked-eye object by people who are blessed with good eyesight and a clear, dark sky, as well as a forehand knowledge of exactly where to look for it. A small telescope may reveal its tiny, greenish disk. Uranus spends all of in the constellation of Aries the Ram. Brightest in August 28 to December Uranus will arrive at opposition to the Sun on November 4. Read more fascinating facts about Uranus!
Neptune is the eighth, and farthest planet in our Solar System and the first whose existence was theorized before its actual discovery. Neptune has 13 moons and takes years to take 1 trip around the Sun! Neptune spends all of in the constellation of Aquarius the Water Carrier.
Learn more about Neptune! So, Venus is practicaly visible entire year!?
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