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The path of Venus through the zodiac constellations during the planet's morning apparition in 2023-24 (move your cursor over the image - or click on the image - to reveal the constellation names in their abbreviated three-letter form - the full names are listed here). Tick-marks indicate the first day of each month. Zodiac constellations are labelled in green and non-zodiac constellations in grey. The numbers along the sides of the chart (Right Ascension and Declination) are co-ordinates of celestial longitude and latitude which are used to locate the position of a celestial body in the night sky. A print-friendly version is available here. |
The Venus Morning Apparition of 2023-2024
After passing through inferior conjunction (passing between the Earth and the Sun) in Cancer, the Crab, on August 13th 2023, Venus swiftly entered the dawn sky as a 'Morning Star' from between mid-August (from mid-Southern latitudes) and late August (from high Northern latitudes). The planet began its 2023-24 morning apparition in twilight, visible low down over the Eastern horizon less than an hour before sunrise (the exact period depending upon the observer's latitude).
Venus at Inferior Conjunction imaged by Tomio Akutsu (Ibaraki Prefecture, Japan) in January 2022, using a 4-inch (102 mm) refractor telescope fitted with a planetary camera and an infrared filter. Venus was only 4°.8 North of the Sun (Image: Tomio Akutsu / ALPO-Japan) |
2 0 2 3 August |
The planet was moving retrograde at this time, crawling Westwards against the background stars of South-eastern Cancer at a rate of about 0°.6 per day. Venus was positioned at a relatively close 0.29 Astronomical Units (AU) from the Earth (43.4 million kms or 26.9 million statute miles), a distance which would continually increase over the next 8½ months, through to the end of the apparition.
Venus reached a solar elongation (angular distance from the Sun) of 10° West on August 17th. On August 18th, as the planet was becoming visible from much of the world, Venus was positioned 8°.0 South of the ecliptic (the path of the Sun, which the Moon and planets follow very closely), which is about the furthest away from the ecliptic that the planet can attain when viewed from the Earth. Venus reached 15° West of the Sun on the 21st. The planet shone at an apparent magnitude of -4.0 and its apparent diameter (its angular width as seen from the Earth) was a sizeable 55" (i.e. 55 arcseconds, where 1 arcsecond = 1/3600th of a degree). In late August Venus rose about 1½ hours before sunrise, barely gaining any significant altitude (or elevation, i.e. the angle above the horizon) before disappearing from view into the twilight.
As it pulled away from the Sun, telescopes pointed towards Venus showed a large, slender, Eastward-facing crescent, rippling in the Earth's turbulent atmosphere. The planet's phase (i.e. the percentage of the disk which is illuminated) was only around 5% (phase = 0.05). At this early stage of the apparition, dedicated telescopic observers of Venus began their search for the elusive Ashen Light, which is a faint glowing of the night side of Venus through its thick clouds. The phenomenon is believed to be caused either by the planet's surface glowing red hot (due to its extremely high surface temperature) or due to electrical activity in its dense atmosphere. Observers searching for the Light will normally use ultraviolet and/or infrared filters in order to help reveal it, an occulting bar often being used to block the bright, visually-intrusive crescent from view. Observers in Equatorial and Southern latitudes were best placed to view the Light at this stage of the apparition due to the planet's higher altitude before sunrise.
While moving retrograde, on August 23rd, Venus passed 3°.1 South of the star Acubens ( Cnc or Alpha Cancri, mag. +4.2), which is located at the South-eastern corner of the Crab constellation's lambda-shaped () pattern.
2 0 2 3 September |
By early September Venus' apparent diameter had shrunk slightly to around 50" (50 arcseconds); it would continue to shrink throughout the apparition, as it slowly receded from the Earth in space (click here to see how Venus typically appears through a small telescope at various phases).
Whilst in Cancer Venus had been describing a slow, counter-clockwise loop against its background stars, initially moving in a WNW direction but now moving NNW. On September 3rd the planet's Westerly motion ceased as it reached a stationary point some 2°.7 South-west of Acubens. Venus reached 30° West of the Sun on the following day. The planet briefly travelled Northwards before curving around towards the NNE, then began direct (or prograde) motion, which is the prevailing direction of travel of the planets in the night sky (during this particular apparition, Venus would spend some 88% of the time moving direct). Venus again passed Acubens - this time passing only 28' (28 arcminutes or 0°.46, where 1 arcminute = 1/60th of a degree) to the South of the star - on September 14th.
By mid-September Venus was rising in darkness from across the inhabited world. Around this time the planet Mercury (magnitude +0.7), having just passed its Western stationary point, entered the morning sky in the first paired apparition between the two planets to take place during Venus' 2023-24 morning apparition (a paired apparition being when the two planets are visible together for a prolonged period of time, either in the morning sky or the evening sky). As it emerged Mercury was positioned in central Southern Leo, some 24° to the East of Venus. This particular apparition of Mercury favoured Northern hemisphere observers due to the steep angle of the ecliptic over the Eastern horizon at dawn at this time of year. The two planets were closest together on September 18th when they came to within 23°.1 of each other. They appeared to move together against the background stars over the next couple of days, being 23°.2 apart, before Mercury - by now in South-eastern Leo - began to accelerate away Eastwards from Venus at a rate of about 0°.65 per day. The waning crescent Moon was in the vicinity of Venus and Mercury from September 11th to 14th.
A Crescent Venus sketched by Paul G Abel (Leicester, UK) in September 2015, one Venus-cycle prior to 2023-24. Venus was 30% illuminated and almost 36" across. Abel used an 8-inch (203 mm) Newtonian reflector telescope at 250x and 167x magnifications (Image: Paul G Abel / ALPO-Japan) |
Venus attained its greatest brilliancy for this apparition (at mag. -4.7) on September 19th. This is the position in the planet's orbit when its phase, its apparent size and its apparent magnitude combine to best visual effect, as seen from the Earth. At greatest brilliancy in the 2023-24 morning apparition, Venus was positioned 40° West of the Sun with a 28% illuminated crescent (phase = 0.28) and an apparent diameter of 37".7.
At 07:23:54 UT on September 22nd, as seen from a segment of the Earth bounded roughly between longitude lines of 22° West and 60° West, Venus was seen to occult (pass in front of) a seventh-magnitude star, blocking it from view for up to 24 minutes. The star, known by the designations HIP 45363 and TYC 0822-00058-1, is located in South-eastern Cancer and shines at a dim magnitude +7.4, which is below naked-eye visibility but easily within reach of binoculars and small telescopes. The occultation was visible in twilight and/or darkness from Greenland, Labrador (East coast), Newfoundland, the mid-Atlantic Ocean (from where the maximum duration was observed), the Azores, Cape Verde Islands and Eastern Brazil. The star disappeared behind Venus' bright limb and re-appeared from behind its dark limb. For further details, see the Belgian VVS website. Later that same day, Mercury attained its greatest Western elongation, reaching 17°.8 West of the Sun and shining at magnitude -0.2.
Venus entered the constellation of Leo, the Lion, on September 25th.
Mercury headed out of view in the dawn twilight at month's end, by which time it had brightened to magnitude -0.9 and had extended its apparent distance to 29° East of Venus.
2 0 2 3 October |
On October 1st Venus passed 58' (0°.96) North of the star Subra ( Leo or Omicron Leonis, mag. +3.5), which is located at the tip of the Lion's foreleg.
Between October 3rd and 13th, Venus was positioned to the South of the asterism (star pattern) commonly known as the Sickle of Leo, at the Western end of the constellation, which appears to the naked-eye as a backward question-mark (). The passage started with Venus passing 12°.9 South of Ras Elased Australis ( Leo or Epsilon Leonis, mag. +2.9), at the upper North-western end ('pointed end') of the sickle.
At the base of the Sickle of Leo (the 'dot' of the backward question-mark) is Leo's brightest star, Regulus ( Leo or Alpha Leonis, mag. +1.3). Venus passed 2°.3 South of the star on October 10th. Regulus is positioned less than 0°.5 from the ecliptic so it is occasionally occulted by planets and - more frequently - by the Moon. Venus last occulted Regulus in July 1959 and will next occult the star during its morning apparition in October 2044.
On October 13th Venus passed 10°.8 South of the star Algieba (1 Leo or Gamma-1 Leonis, mag. +2.3), located at the base of the Lion's neck (although the name is Arabic for 'the forehead'). It is a double star with golden-yellow components (1 Leo and 2 Leo) of magnitudes +2.3 and +3.6, separated by an angular distance of 4".7. The pair are about 130 light years from Earth (where 1 light year = 63,240 AU) and they orbit each other in a period of 554 years. The star is easily split in small telescopes and is considered to be one of the finest double stars in the night sky. In 2009 an exoplanet (or extra-solar planet, i.e. a planet outside our Solar System) was detected orbiting 1 Leo, designated Gamma-1 Leonis b. It is believed to be a gas giant with a mass equivalent to about nine Jupiters, taking 428 days to complete one orbit of its parent star. At the time of writing (February 2023), more than 5,000 exoplanets have been discovered, orbiting fewer than 4,000 stars within the Milky Way galaxy. Only a few hundred of these stars are visible to the naked eye (i.e. brighter than magnitude +6.0); several examples of which will be discussed in this article.
Around mid-October, observers at high and mid-Northern latitudes saw Venus attain its highest altitude in the sky before sunrise for the 2023-24 apparition. At latitude 60° North, the planet rose nearly five hours ahead of the Sun, attaining an altitude of 30° above the South-eastern horizon at 30 minutes before sunrise. For mid-Northern observers, the planet rose four hours before the Sun, reaching a decent 38° above the South-eastern horizon at 30 minutes before sunrise. For naked-eye observers in the Northern hemisphere, the 2023-24 apparition was the best of Venus' five morning apparitions over the planet's 8-year cycle (for more details, see the accompanying article describing The Venus 8-year Cycle). Conversely it was the worst morning apparition for Southern hemisphere observers, the planet typically attaining lesser altitudes above the horizon at dawn than in the other morning apparitions.
On October 17th Venus passed 1°.1 South of Leo (Rho Leonis, mag. +3.8), a supergiant variable star located beneath the Lion's underbelly, roughly mid-way between its foreleg and hind leg.
Venus near Greatest Elongation imaged by Imre Ferenczi (Budapest, Hungary) in October 2015, one Venus-cycle prior to 2023-24. Ferenczi used a 5-inch (127 mm) Newtonian reflector fitted with a digital camera and a neutral density filter (Image: Imre Ferenczi / ALPO-Japan) |
At 2144 UT on October 23rd Venus reached its greatest Western elongation (46°.4 West of the Sun), positioned near Leo's border with Sextans, the Sextant, some 13°.6 ESE of Regulus. Venus' apparent magnitude had faded slightly to -4.3 and its apparent diameter had reduced to 24".0. The planet was now moving towards the ESE at a rate of about 1° per day. Although the planet's greatest elongation from the Sun took place on October 23rd, Venus was in fact positioned at precisely 46°.4 elongation for an eight-day period from October 20th through to the 28th.
In theory, greatest elongation is the time at which the planet's terminator (the line seperating the light and dark sides of the planet) appears perfectly straight through telescopes, essentially dividing Venus into two perfect halves; this is known as the dichotomy. However, telescopic observers often report the straight terminator several days earlier or later than the greatest elongation date; typically early in evening apparitions and late in morning apparitions. This is known as the phase anomaly or Schröter's Effect (after the German astronomer Johann Schröter, who first observed the phenomenon in 1793) and is thought to be due to Venus' dense atmosphere scattering the sunlight. In the 2023-24 apparition, therefore, telescopic observers could expect to see a 50% phase on or around October 27th.
Venus crossed to the North of the ecliptic at around 10 hours UT on October 25th.
In late October, observers situated at low-Northern and Northern Tropical latitudes saw the planet attain its highest altitude before sunrise for the 2023-24 morning apparition. At 30° North, Venus rose 3½ hours ahead of the Sun, reaching 38° above the ESE horizon at half-an-hour before sunrise. Elsewhere the planet rose five hours before sunrise (at 60° North), 4¼ hours before sunrise (at 50° North) and three hours before the Sun (at Equatorial latitudes). Mid-Southern latitudes saw the planet rise two hours ahead of the Sun. In fact, when assessed in terms of horizon altitude and visibility duration before sunrise, the 2023-24 morning apparition of Venus was best seen overall from Northern Tropical latitudes.
Venus passed 10°.1 South of the star Chertan ( Leo or Theta Leonis, mag. +3.3), located at the top of the Lion's rear leg, on October 27th. Prior to standardisation by the International Astronomical Union (IAU) in 2016 the star was also known as Coxa or Chort. At the same moment the planet passed 15°.2 South of the star Zosma ( Leo or Delta Leonis, mag. +2.7), positioned at the rump of the Lion.
Also on the 27th, at 1010 UT, the distance between the Earth and Venus was the same as that between the Sun and Venus, at 0.7203 AU (107.7 million kms or 66.9 million miles). Seen from a point in space far above the Earth's North pole, the Earth, Venus and the Sun now appeared form an isoscelene triangle in space, with Venus positioned at the apex.
On October 29th Venus passed 1°.4 South of the star Leo (Sigma Leonis, mag. +4.0), positioned at the foot of the Lion's hind leg.
For Equatorial observers, late October and early November saw the planet attain its highest altitude above the horizon before sunrise for the current apparition. Here Venus rose 2¾ hours before the Sun, reaching 34° above the Eastern horizon some 30 minutes ahead of sunrise.
2 0 2 3 November |
Venus entered Virgo, the Virgin, on November 2nd. At 2311 UT on November 5th Venus passed just 19' (0°.31) to the North of the star Zavijava ( Vir or Beta Virginis, mag. +3.6). Before standardization by the IAU in 2016 the star was also known by the names Zavijah, Zavyava or Alaraph.
On November 9th skywatchers across most of the world saw the Moon pass very close to Venus. From around 09 hours UT, however, as seen from a part of the Northern hemisphere, the planet was occulted by the 25-day old waning crescent Moon, thereby blocking the planet from view, in an event known as a lunar occultation. The event was visible in darkness from North-western Greenland and extreme Northern Canada (Ellesmere Island). It was visible in twilight from Eastern Greenland, Iceland, Svalbard, Norwegian Sea, Barents Sea, Greenland Sea and central Northern Russia (Novaya Zemlya, Kara Sea, Northern Yamalo-Nenets). Since Venus was near its maximum elongation from the Sun, the event could also be safely viewed in daylight, whilst taking the necessary precautions to shield the Sun from direct view. Daylight observation was possible from Europe (except Portugal & South-western Spain), Western Russia, Western Asia, North-eastern Africa (North-east Algeria, Tunisia, Libya, Egypt, Northern Sudan) and the Middle East (except Oman, Yemen and Eastern UAE). Venus disappeared behind the Moon's bright crescent limb and, depending upon the observer's location, re-appeared up to 77 minutes later from behind its dark limb (maximum duration being from Eastern Europe). Further details of this event can be found by following the link in the 'Moon near Venus Dates' section below.
Venus crossed the celestial equator - where the declination (symbol ) of a celestial body is 0° - heading Southwards on November 11th, the planet now rising due East across the inhabited world. At 0122 UT on November 13th Venus passed just 5' (0°.08) North of the star Zaniah ( Vir or Eta Virginis, mag. +3.8).
Greatest elongation day long having passed, telescopes showed a 60% illuminated (i.e. slightly gibbous) phase in mid-November; the phase would remain gibbous through the rest of the apparition. The apparent diameter had now reduced to around 20" and the planet shone at an apparent visual magnitude of -4.3.
On November 17th Venus passed 5°.6 North of Vir (Chi Virginis, mag. +4.6), a star which was found to have an exoplanet (HD 110014 b) in 2009. It is thought to have a mass equivalent to 11 Jupiter masses, orbiting Chi Virginis at a distance of 2.1 AU in a period of 835 days.
At 0548 UT on November 18th Venus passed 1°.1 South of the double star Porrima ( Vir or Gamma Virginis, mag. +3.5), named after one of the Roman goddesses of prophecy. At 20:05:24 UT on the same day the planet occulted a magnitude +6.7 star with the designations FK 5124, HIP 62141 and TYC 4952-01080-1. The event was visible in twilight/darkness from South-western Australia, to the South of a line extending from Onslow (WA) to Karlamilyi National Park (WA). A graze was observable from along the aforementioned line. Maximum duration (4 minutes) took place in twilight from the South-western tip of Western Australia. The star disappeared behind Venus' bright limb and re-appeared from behind its dark limb. See the VVS website for further details.
On November 21st Venus passed 7°.2 South of the star Minelauva ( Vir or Delta Virginis, mag. +3.4). Prior to IAU standardisation 2017 the star was sometimes known by its shortened name Auva.
At 2046 UT on November 24th Venus passed just 16' (0°.26) North of the double star Vir (Theta Virginis, mag. +4.4), which the planet will occult in November 2044 during its 2044-45 morning apparition.
At 2140 UT on November 26th the planet passed 12°.3 North of 61 Vir (61 Virginis, mag. +4.7), a star which, since 1996, has been found to have three exoplanets (61 Virginis b, c and d). At 28 lights years distant, they orbit their parent star at a distance which would place them within the equivalent orbit of Venus in our own Solar System. All three are considered to be Neptune-like, having a mass of between 5 and 23 Earths and making one orbit of the star in 4 days, 38 days and 123 days, respectively.
On November 28th Venus passed 4°.4 North of Virgo's brightest star, Spica ( Vir or Alpha Virginis, mag. +1.0), a blue-white star which dominates the South-eastern region of the constellation. At 12:31 UT on the same day the planet passed through perihelion (its closest orbital point to the Sun), when it was 0.7184 AU (107.4 million kms or 66.8 million miles) from the Sun. Aphelion (its furthest distance from the Sun) would be reached in mid-March 2024.
2 0 2 3 December |
In early December, observers situated at low-Southern latitudes saw Venus reach its maximum altitude before sunrise. At latitude 15° South the planet attained an altitude of 29° in the East at 30 minutes before sunrise; here the planet rose 2½ hours before the Sun. Meanwhile at 60° North latitude, Venus was rising 4¾ hours before the Sun, attaining an altitude of 19° in the SSE at 30 minutes before sunrise. At mid-Northern latitudes the planet rose between 3¼ hours (30° North) and four hours (50° North) before the Sun, reaching an altitude of 32° and 25° in the South-east at 30 minutes before sunrise, respectively. At the Equator the planet rose 2¾ hours ahead of the Sun, climbing to 33° high in the ESE at 30 minutes before sunrise while at mid-Southern latitudes the planet rose two hours before the Sun and reached 19° high in the East at a half-hour before sunrise.
Since inferior conjunction Venus had been receding from the Earth at an average rate of about 937,600 kms (582,600 miles) per day. At 1452 UT on December 4th, the planet was positioned at precisely 1.0000 AU from the Earth, i.e. the same distance as the average distance of the Earth from the Sun (149.5 million kms or 92.9 million statute miles). Viewed from a position in space far above the Earth's North Pole, the Sun, Venus and the Earth now formed an isosceles triangle, with the Earth positioned at the apex.
The Crescent Moon, Venus and Spica almost lined up in the early hours of December 4th 2018 during Venus' 2018-19 morning apparition. Venus was within 0°.5 of the same position in Virgo at 0920 UT on December 5th 2023 (click on the thumbnail for a larger version) |
At 0144 UT on December 9th Venus passed 42' (0°.7) South of the star Kang ( Vir or Kappa Virginis, mag. +4.2), which is located near the constellation's South-eastern border with Libra, the Balance. In Chinese astronomy Kang was a constellation and a name given to the second lunar mansion. Derived from 'Kàng Xiù' meaning 'Neck', the constellation represented the neck of a Blue Dragon, formed by the stars Vir, Vir (Lambda Virginis or Khambalia, mag. +4.5), Vir (Iota Virginis or Syrma, mag. +4.1) and Vir (Phi Virginis, mag. +4.8). The star was named by the IAU's Working Group on Star Names (WGSN) in 2017.
Venus entered Libra at 0012 UT on December 11th, passing 2°.0 North of the double star Zubenelgenubi (2 Lib or Alpha-2 Librae, mag. +2.8) on December 17th. The planet's solar elongation reduced below 40° on December 19th, and on the following day Venus passed 10°.3 North of the star Brachium ( Lib or Sigma Librae, mag. +3.3), which is located at the base of the Scales.
Venus passed 6°.5 South of the star Zubeneschamali ( Lib or Beta Librae, mag. +2.5), the Northernmost star of the Balance figure, on December 22nd. The late astronomer Sir Patrick Moore once described Zubeneschamali as being 'the only naked-eye star which is said to have a greenish tint - though most observers will certainly class it as white!'.
At 0152 UT on December 25th (Christmas Day) Venus passed just 1'.9 (0°.031) North of the star 1 Lib (Zeta-1 Librae, mag. +2.8), which the planet will occult one Venus-cycle hence on December 24th 2031.
On December 26th the planet passed 2°.3 South of the star Zubenelhakrabi ( Lib or Gamma Librae, mag. +4.0), a name which was alternatively spelled Zuben Elakrab before IAU standardisation in 2017. It is commonly said to mean 'claw of the Scorpion' although it originates from a much earlier Sumerian name meaning 'balance of heaven'. Two exoplanets were confirmed as orbiting Zubenelhakrabi in 2018, designated Gamma Librae b and Gamma Librae c. Some 155 light years distant, they are both gas giants, equivalent to one and 4½ Jupiter masses respectively, taking 415 days and 2.6 years to orbit their parent star. They orbit Zubenelhakrabi at distances of 1.2 AU and 2.1 AU, respectively.
On December 30th Venus passed 1°.5 South of the star Lib (Theta Librae, mag. +4.1), located in Eastern central Libra. By this time the planet had faded slightly to magnitude -4.0, its apparent diameter had reduced below 15" and its gibbous phase was around 77% illuminated.
In late December Mercury (mag. +1.3) entered the morning sky in the second paired apparition of Venus' 2023-24 morning apparition. It was Mercury's fourth and final morning apparition of the year and its seventh overall (including evening apparitions). As it emerged, Mercury was in Southern Ophiuchus, positioned some 23°.6 to the East of Venus. In the closing days of 2023 and into the first few days of the new year, Venus approached a slowing Mercury at a rate of about 1°.1 per day. Mercury was 22°.7 ESE of Venus at midnight UT on December 30th and 21°.1 to the East of Venus at midnight UT on the 31st.
At 0745 UT on the 31st, Venus passed 7°.6 North of Fang ( Sco or Pi Scorpii, mag. +2.8), a star located in the neighbouring constellation of Scorpius, the Scorpion; specifically in the head of the Scorpion. The name was formally assigned to the star by the IAU in 2017 after the fourth lunar mansion in ancient Chinese astronomy. At 1440 UT on the same day the planet passed 4°.0 North of the star Dschubba ( Sco or Delta Scorpii, mag. +2.2), also in the Scorpion's head, before entering Scorpius itself at 2307 UT.
2 0 2 4 January |
At midnight UT on January 1st Mercury (mag. +0.7) was positioned 19°.6 to the ESE of Venus. At 1427 UT on the same day Venus passed 56' (0°.93) North of the striking double star Acrab (1 Sco or Beta-1 Scorpii, mag. +2.6). Its two blue-white components (1 Sco and 2 Sco), of magnitudes +2.6 and +4.9 respectively, are separated by 13".7 and are easily seen in small telescopes. Beta-1 Scorpii is itself also double, having a tenth-magnitude companion positioned less than an arcsecond away, separable only in larger telescopes. At 2105 UT on the same day the planet passed 1°.7 North of another blue-white star, Jabhat al Akrab (1 Sco or Omega-1 Scorpii, mag. +3.9), whose Arabic name translates as 'forehead of the Scorpion'.
At midnight UT on January 2nd Venus passed 1°.9 North of the yellow star 2 Sco (Omega-2 Scorpii, mag. +4.3), which is located just 14'.7 (0°.245) to the South-east of Jabhat al Akrab. At 2138 UT on the same day, Venus passed 16' (0°.26) North of the multiple star named Jabbah ( Sco or Nu Scorpii, mag. +4.0). Together, the stars 1 Sco, 2 Sco, Dschubba, Acrab and Jabbah form a distinctive asterism in Northern Scorpius.
In early January, observers situated at Southern Tropical latitudes saw Venus reach its maximum altitude before sunrise. At latitude 25° South the planet rose 2½ hours before the Sun, reaching 25° high in the East at 30 minutes before sunrise.
Mercury reached its Western stationary point in Southern Ophiuchus on January 2nd, positioned 18º.2 East of Venus. At midnight UT on the 3rd the planet was positioned 17°.2 East of Venus .
On January 4th Venus passed 5º.9 North of the variable star Alniyat ( Sco or Sigma Scorpii, mag. +2.9v). The planet entered the non-zodiacal constellation of Ophiuchus, the Serpent-Bearer, on the following day.
Mercury was positioned 15°.2 East of Venus at midnight UT on January 5th. On January 6th Venus passed 6º.4 North of the Scorpion's brightest star Antares ( Sco or Alpha Scorpii, mag. +1.0v), which shines with an unmistakable orange-red hue. It is both a binary star and a semi-regular variable, fluctuating between magnitude extremes of +0.9 and +1.8 over the course of four to five years.
Over the next fortnight Venus passed several stars which have been assigned 'new' names by the IAU in recent years; throughout this article they are shown in yellow-green type. On January 7th Venus passed 8°.0 North of the star Paikauhale ( Sco or Tau Scorpii, mag. +2.8), a name which is Hawaii'an for a vagabond.
Mercury was positioned 12°.8 East of Venus at midnight UT on the 9th, entering Sagittarius, the Archer, on January 10th. The waning crescent Moon passed in the vicinity of the planetary pair from January 8th to 10th.
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At 1045 UT on January 10th Venus passed 13°.5 North of Larawag ( Sco or Epsilon Scorpii, mag. +2.2), which is an Aboriginal name from the Wardaman culture of Northern Australia; it is positioned about half-way along the Scorpion's tail. At 1845 UT on the same day the planet passed 17°.1 North of the stars Xamidimura (1 Sco or Mu-1 Scorpii, mag. +2.9) and Pipirima (2 Sco or Mu-2 Scorpii, mag. +3.5), which are located 3º.5 South of Larawag. The two stars are separated in the night sky by just 5'.7 (0º.1), making them appear as a double star, however this is a line-of-sight effect and they are not physically related. Xamidimura is an eclipsing binary of the Beta Lyrae variable star type whilst Pipirima is a blue-white subgiant star. Xamidimura is the historical name given to the star by the Khoikhoi people of South Africa; it means 'eyes of the lion'. The name Pipirima comes from Polynesian mythology. It refers to a Tahitian story of two inseparable twins (Pipirima and Réhua) who fled from their parents and became stars in the night sky. In 2022 an exoplanet was confirmed as orbiting Pipirima; considered to be a gas giant, its mass is equivalent to that of 14 Jupiters, taking 1,252 years to orbit Pipirima at a distance of 242 AU.
From around January 10th the planet Mars (mag. +1.4), in Western Sagittarius, emerged into the dawn sky at the start of its two-year-long 2024-25 apparition, joining the two inferior planets positioned to its West. Through the rest of the month Venus closed in on the Red Planet at an average rate of 0°.76 per day, whilst Mercury closed in on the planet at around 0°.44 per day. At midnight UT on January 10th, Mars was positioned 20°.5 to the ESE of Venus and 8°.4 to the ESE of Mercury.
Mercury, now magnitude -0.1, was positioned 12°.0 East of Venus at midnight UT on January 11th. The planet reached its greatest Western elongation in Western Sagittarius on January 12th, positioned 23°.5 from the Sun, 11°.6 to the East of Venus and 7°.8 to the WNW of Mars. At midnight UT on January 13th Mars was positioned 19°.1 to the East of Venus and 7°.7 to the ESE of Mercury.
Around mid-January, observers at mid-Southern latitudes saw Venus attain its highest altitude in the sky before sunrise for the 2023-24 apparition. At 35° South, the planet rose 2½ hours before the Sun, reaching an altitude of around 22° in the ESE at 30 minutes before sunrise. Elsewhere, Venus rose in the SSE two hours before sunrise (at 60° North), in the South-east some 2¼ hours before sunrise (at mid-Northern latitudes) and in the ESE some 2½ hours before sunrise (at the Equator).
From higher Northern latitudes, Venus was now beginning to rise in twilight again; from here the shallow angle of the ecliptic to the South-eastern horizon at dawn, coupled with the permanently shallow rising angle of celestial bodies at such high latitudes, meant that by the time the planet rose, the Sun was not far below the horizon. Observers at these latitudes only had a couple more weeks in which to view the planet's morning apparition, at least by naked eye.
At midnight UT on January 15th Mercury was positioned 11°.2 East of Venus. On the same day Venus passed 5°.0 North of the star Guniibuu (36 Oph A or 36 Ophiuchi A, mag. +5.1). It is an Australian Aboriginal name meaning a robin red-breast, derived from Euahlayi-Kamilaroi culture. Guniibuu is one component of a pair of orange dwarf stars (A and B) which are easily split in small telescopes.
At midnight UT on the 16th, Mars was located 17°.7 to the East of Venus and 6°.6 to the ESE of Mercury. Later that same day Venus passed 3°.2 North of Oph (Theta Ophiuchi, mag. +3.2), the Southernmost bright star in Ophiuchus.
Venus and Mercury came closest to each other on January 18th, when they were 11°.1 apart, Venus being in Southern Ophiuchus and Mercury in Western Sagittarius. Mars was positioned 16°.5 to the East of Venus and 5°.5 to the ESE of Mercury on the same day.
Having spent a fortnight in Southern Ophiuchus, Venus entered Sagittarius on January 20th.
On January 21st the planet passed 14°.8 North of Fuyue (G Scorpii, mag. +3.2), which is positioned at the tail-end of the Scorpion. Fu Yue was a Chinese labourer who became a wise minister and a chancellor of the Emperor Wu Ding (ca. 1250-1192 BC) of the Shang dynasty. After Fu Yue's death he is said to have become part of a constellation known as The Sieve, situated in the Tail mansion (Wei Xiù) in ancient Chinese astronomy.
Mars was positioned 14°.8 to the East of Venus and 3°.6 to the East of Mercury at midnight UT on January 22nd.
For a period of about 18 hours on January 24th, Venus passed about 2º North of the sixth-magnitude gaseous nebula commonly called the Lagoon Nebula (M8 or NGC 6523). With an apparent dimension of 90' by 40', the nebula is visible to the naked-eye from dark sites and is a spectacular sight through larger telescopes - particularly those fitted with nebular filters. The planet's passage of the nebula began at about 01 hours UT and ended at about 19 hours UT.
Positioned a short distance to the NNW of the Lagoon Nebula is another gaseous nebula called the Trifid Nebula (M20 or NGC 6514). Its brightest region is roughly elliptical in shape and measures 29' by 27'. Seen through telescopes under dark skies, three dark dust lanes can be seen, from which the nebula gets its name. At the centre of the nebula is a double star comprising components of 7th and 8th magnitude. Venus passed 30' (0°.5) North of the Trifid Nebula over the course of 5½ hours from 0115 UT to 0650 UT on the 24th.
Venus appears between Clouds in this photograph taken by the writer during the planet's morning apparition in November 2020. Venus was about 30° West of the Sun and shone at magnitude -4.0 (click on the thumbnail for the full-size picture).
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Between January 24th and February 5th Venus passed just to the North of Sagittarius' famous asterism, the Teapot, which comprises eight stars of third-magnitude or brighter (although since the constellation was only now beginning to emerge into the dawn sky, they were not all visible from all locations at this time of the year). The passage started at 1850 UT on the 24th when the planet passed 8° North of Alnasl ( Sgr or Gamma Sagittarii, mag. +3.0), positioned at the front of the Archer's bow. Prior to IAU standardisation in 2016 it was also known by the names Nash or Alnasr, among others.
At midnight UT on January 25th Mars was positioned 13°.4 to the East of Venus and 1°.7 to the East of Mercury.
On January 26th Venus passed 1°.4 South of Polis ( Sgr or Mu Sagittarii, mag. +3.8v), an eclipsing binary star with a tiny brightness variation of ±0.1 magnitudes; it is not located within the Teapot asterism. Early star guides often identified a different asterism in this region of the night sky: known as the Milk Dipper, it comprised the Teapot's 'handle' stars together with Kaus Borealis (see below) and Polis, the latter of which is located just to the North-west of the Teapot. The Milk Dipper was envisaged as a ladle dipping into the rich Milky Way, though it seems to have fallen out of recognition in recent decades.
At 1420 UT on January 27th Venus passed 7°.3 North of Kaus Media ( Sgr or Delta Sagittarii, mag. +2.7) which marks the centre of the Archer's bow; before IAU standardisation it was also known by the names Kaus Meridionalis and Kaus Medius. At 15 hours UT on the same day Venus attained its most Southerly declination of the apparition, at -22° 29' 3".5 ( = -22°.4843 in decimal form). Across the inhabited world the planet now rose at its most Southerly position on the local horizon for this apparition. This would be towards the South-east at latitudes far away from the Equator and towards the ESE at Equatorial latitudes. Also on the 27th, at 1607 UT, Mars (mag. +1.3) and Mercury (mag. -0.2) were involved in a close conjunction in central Sagittarius, Mercury passing 14' (0°.23) to the North of the Red Planet. At the moment of conjunction the pair were positioned 12°.2 East of Venus and 19°.8 West of Sun.
In late January, observers at latitudes around 45° South saw Venus attain its highest altitude in the sky before sunrise for the current apparition. Here the planet rose 2½ hours before the Sun, reaching an altitude of around 20° high in the ESE at 30 minutes before sunrise.
At midnight UT on January 28th Mars was positioned 12°.0 to the East of Venus. Also on the 28th, Venus passed 11º.9 North of Sagittarius' brightest star Kaus Australis ( Sgr or Epsilon Sagittarii, mag. +1.8), which marks the base of the Teapot's spout. Given that this star was designated the fifth letter of the Greek alphabet, one might expect Kaus Australis to be the fifth-brightest star in the constellation. However, it is one of many examples in the night sky where the brightest star in the constellation was not assigned the correct letter - namely, alpha (). Later on the same day Venus passed 2º.9 North of the aforementioned star Kaus Borealis ( Sgr or Lambda Sagittarii, mag. +2.8) which marks the top of the Teapot asterism (and the top of the Archer's bow).
At 1110 UT on January 30th the planet passed 1º.4 North of the globular cluster M22 (NGC 6656) which is considered to be one of the finest globulars in the night sky. Its integrated magnitude is about +5.9 and it has an apparent diameter of 24'. It is just visible to the naked-eye from dark sites, is easily seen through binoculars and is beautifully resolved in telescopes.
At midnight UT on January 31st Mars was positioned 10°.6 to the East of Venus.
2 0 2 4 February |
In early February Venus passed North of the four stars which form the 'handle' of the Teapot. The planet passed 4°.6 North of Sgr (Phi Sagittarii, mag. +3.1) on February 1st and 4°.0 North of the constellation's second-brightest star Nunki ( Sgr or Sigma Sagittarii, mag. +2.0) at 0020 UT on February 3rd. At 1050 UT that same day, and away from the Teapot, Venus passed 1°.1 South of the star 2 Sgr (Xi-2 Sagittarii, mag. +3.5), which marks the forehead of the Archer figure.
At 1120 UT on February 4th,Venus passed 7°.7 North of Ascella ( Sgr or Zeta Sagittarii, mag. +2.6), located at the base of the Teapot's handle. At 1820 UT on the same day the planet passed 24' (0°.4) South of the star Sgr (Omicron Sagittarii, mag. +3.7), one of three stars marking the Archer's head.
From early February, observers situated at high-Northern latitudes were the first to lose sight of Venus as it headed into the bright dawn twilight. Over the next three months the apparition would slowly end in a Southward direction, from the Northern hemisphere into the Southern.
Venus' solar elongation fell below 30° West on February 5th. At 0520 UT on the same day the planet passed 5°.6 North of Sgr (Tau Sagittarii, mag. +3.3) which marks the Easternmost point of the Teapot. At 1710 UT it passed 1°.0 South of the star Albaldah ( Sgr or Pi Sagittarii, mag. +2.9), positioned at the top of the Archer's head; Venus will occult this star during the course of its morning apparition in February 2035.
Venus Cloud Features in Ultraviolet imaged by Massimo Bianchi (Milan, Italy) in July 2022 using a 10-inch (260 mm) Maksutov Cassegrain reflector telescope fitted with CMOS camera and filter. Note the planet's characteristic 'Y-shaped' cloud feature (Image: Massimo Bianchi / ALPO-Japan) |
At midnight UT on February 6th Mars was positioned 7°.7 to the East of Venus and 6°.7 West of Mercury. At around 17 hours UT that same day Mercury (mag. -0.3), Mars (mag. +1.3) and Venus (mag. -3.8) were seen to be equi-distant along 14°.7 in celestial longitude, the apparent angular distance between Mercury and Mars (and Mars and Venus) being 7°.4. Mercury was located in Capricornus and the other two were in Sagittarius. Mercury fell below 15° solar elongation at this time and was fast heading out of view in the dawn twilight.
On February 8th at 2003 UT Venus passed just 4'.5 (0°.075) North of the star 50 Sgr (50 Sagittarii, mag. +5.6), which the planet will occult three Venus-cycles hence on February 7th 2048.
Venus continued its way through Sagittarius to the constellation's much fainter Eastern region. The planet passed 3°.5 North of the star 52 Sgr (52 Sagittarii, mag. +4.6) on February 10th, then on the 14th it passed 5°.5 North of Terebellum ( Sgr or Omega Sagittarii, mag. +4.7), a Latin name which derives from an original Greek word meaning 'quadrilateral'. Terebellum is one of a group of four moderately-bright stars positioned within 2° of each other in the 'rump' of the Archer figure. They were named as such by Claudius Ptolemy (ca. 100-170 AD) in his famous star catalogue, the Almagest.
Mars entered Capricornus at 01 hours UT on February 13th. Venus passed to the South of the ecliptic on the same day, itself entering Capricornus on the 16th.
By mid-February Venus was rising in twilight from mid-Northern latitudes; observers here had between three weeks (50° North) and six weeks (40° North) in which to continue observing the planet's morning apparition by naked eye.
On February 18th Venus passed 7°.2 South of Prima Giedi (1 Cap, or Alpha-1 Capricorni, mag. +4.2) and, soon afterwards, Algedi (2 Cap or Alpha-2 Capricorni, mag. +3.6). Prior to IAU standardisation in 2016 the latter was also known as Secunda Giedi. Prima Giedi and Algedi are separated in the night sky by 6'.4 (0°.1) and are an easy optical double, meaning that they appear to the naked-eye as a double star but they are not physically related - in this case being 700 light years and 108 light years distant, respectively.
Venus passed 4º.9 South of the variable and multiple star Dabih ( Cap or Beta Capricorni, mag. +3.0v) on February 19th. It is a yellow star with a blue companion of magnitude +6.1, positioned 3'.5 to the West, visible in binoculars and small telescopes.
Mars was positioned 2°.1 to the East of Venus at midnight UT on 18th and 54' (0°.9) to the South-east of Venus at midnight UT on 21st. By midnight UT on the 22nd Mars was only 39' (0°.65) to the SSE of Venus. At 1534 UT that same day Venus passed 38' (0°.63) to the North of Mars in the first of two planetary conjunctions which took place during Venus' 2023-24 morning apparition. A planetary conjunction occurs whenever two planets attain the same celestial longitude in the night sky (i.e. they appear to 'line up' when seen from the Earth). The conjunction was best observed in the Southern hemisphere but could be observed with some difficulty as far North as latitude 38° North. Further details of this and the other planetary conjunction involving Venus during this apparition is given below.
Following conjunction, Venus moved on Eastwards, Mars being positioned 1°.4 to the South-west of Venus at midnight UT on February 25th and 2°.7 to the WSW of Venus at midnight UT on February 28th.
At 0248 UT on February 28th, Venus passed just 2'.7 (0º.045) to the South of the star Theta Capricorni ( Cap, mag. +4.0), at the centre of the Sea-Goat constellation. Through binoculars the two appeared as a striking 'double-star' with white components of wildly differing magnitudes (-3.8 and +4.0).
By late February Venus' elongation had reduced to 25° and it appeared only slightly gibbous through telescopes, showing a 90% illuminated phase and a disk-diameter of around 11", i.e. only half the size it had been in early November and a third of the size it had been in late September. With such a small disk size and a narrow solar elongation, little could now be discerned in the way of the planet's characteristic cloud markings.
2 0 2 4 March |
At midnight UT on March 2nd, Mars was positioned 4°.1 to the WSW of Venus. At 0920 UT on the same day Venus passed 38' (0°.63) North of the star Cap (Iota Capricorni, mag. +4.3), which is positioned at the 'rump' of the Sea-Goat figure.
In early March, observers at mid-Northern latitudes lost sight of Venus as it slipped into the bright ESE horizon, bringing the apparition to an end from these locations. For observers at lower-Northern latitudes the 'observing window' for Venus had reduced to around an hour. At Equatorial latitudes the planet rose about 1½ hours before the Sun, reaching around 14° high in the ESE at 30 minutes before sunrise. Mid-Southern hemisphere observers now had a rapidly shortening window in which to observe the planet, despite its still rising in darkness. At 35° South, Venus rose two hours ahead of the Sun, attaining about 17° in altitude in the Eastern sky at 30 minutes before sunrise.
Several degrees to the North of Venus in early March was the Western half of the constellation of Aquarius, the Water-Bearer (also known as the Water-Carrier or Waterman). Its brightest star is Sadalsuud ( Aqr or Beta Aquarii, mag. +2.9), a name which is Arabic for 'the lucky one of the lucky', its meaning having astrological origins. Some 2º.7 to the South-east of Sadalsuud is the binary star Bunda ( Aqr or Xi Aquarii, mag. +4.7), a name formally assigned by the IAU in 2018 after a Persian lunar mansion. Venus passed 9º.9 South of Sadalsuud on March 4th and 7º.2 South of Bunda on March 5th.
On March 6th, Venus passed 1º.7 North of Nashira ( Cap or Gamma Capricorni, mag. +3.7) and, on March 7th, 1º.7 North of the constellation's brightest star, a variable named Deneb Algedi ( Cap or Delta Capricorni, mag. +2.9v). Together these stars mark the 'tail' of the Sea-Goat.
By midnight UT on March 8th the angular distance between Mars and Venus had extended to 6°.8. Venus entered Aquarius on the following day, passing 1º.1 North of the star Aqr (Iota Aquarii, mag. +4.2) on March 11th. Mars was positioned 8°.2 to the WSW of Venus at midnight UT on March 11th. Two days later (13th) Venus passed 4º.0 South of the star Ancha ( Aqr or Theta Aquarii, mag. +4.1). Between March 14th and 17th the planet was positioned about 10º South of the Water-Bearer's most recognisable feature: an asterism of four stars informally known as the Steering Wheel, centred on Aqr (Zeta Aquarii, mag. +3.6). On some modern star maps this asterism is seen to depict the head of the Water-Bearer figure; such maps are based on the constellations envisaged in the 1950s by the author and illustrator H. A. Rey (1898-1977). On older star maps, such as the Uranographia published in 1801 by Johann Elert Bode (1747-1826), these stars marked the amphora from which the water was poured. Venus passed 9°.9 South of the Steering Wheel's Westernmost star Sadachbia ( Aqr or Gamma Aquarii, mag. +3.9) at 16 hours UT on the 14th.
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Anomalous Venus Cloud Phenomena Since 2016 an unusual phenomema referred to as a cloud discontinuity (or wave discontinuity) has been periodically observed and monitored in Venus' atmosphere by some amateur astronomers. First identified in images taken by the Japanese orbiter Akatsuki in 2015, it is thought to be a type of atmospheric gravity wave. It can only be seen at infrared wavelengths and makes one rotation of the planet every 5 days. The discontinuity is aligned North-South across the planet's equator and is estimated to measure between 2,900-7,000 kms (1,800-4,350 statute miles) long and from 180-340 kms (112-211 statute miles) wide. The cause of the phenomena is not known; one suggestion is that it may be connected with volcanic activity on Venus' surface. The discontinuity is of low-contrast and was captured by António Cidadão (Carcavelos, Portugal) during the planet's 2022 morning apparition on (left) May 25th, (middle) June 4th and (right) September 2nd. Cidadão used a 14-inch (356 mm) Schmidt-Cassegrain reflector telescope fitted with a CMOS camera and a near-infrared filter (Images: António Cidadão / ALPO-Japan) |
At around 04 hours UT on March 16th Venus passed 10°.6 South of the double star 1 Aqr (Zeta-1 Aquarii, mag. +3.7), located at the centre of the Steering Wheel. At 1254 UT on the same day the planet passed just 1'.3 (0°.021) North of the double star Aqr (Sigma Aquarii, mag. +4.8), which is positioned more or less at the centre of Aquarius. The planet will occult this star three Venus-cycles hence on March 15th 2048.
The planet Saturn, in central Aquarius, emerged into the dawn sky from mid-month at the start of its 2024-25 apparition. It was positioned 5°.5 to the ENE of Venus at midnight UT on the 17th (with Mars now 11° to the WSW of Venus). At around 12 hours UT on the same day Venus passed 10° South of Aqr (Eta Aquarii, mag. +4.0), located at the Eastern end of the Steering Wheel, thereby completing its passage of the asterism.
Venus was approaching Saturn at a rate of 1°.1 per day. At midnight UT, Saturn was 4°.4 to the ENE of Venus on March 18th and 3°.3 to the ENE of Venus on March 19th. Venus' solar elongation fell below 20° West on the same day, then on the 20th the planet passed the aphelion point in its orbit, where it was furthest away from the Sun at 0.7282 AU (108.9 million kms or 67.7 million statute miles).
Saturn was positioned 1°.1 to the East of Venus at midnight UT on March 21st. At 0525 UT on the same day Venus passed 59' (0°.98) South of the star Aqr (Lambda Aquarii, mag. +3.9), which the planet occulted during its 2014 morning apparition.
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At midnight UT on March 22nd Saturn was located only 19' (0°.31) to the SSE of Venus. At 0159 UT on the same day Venus passed 20' (0°.33) to the South of Saturn in the second and final planetary conjunction of Venus' morning apparition. Taking place when the pair were only 19° away from the Sun, it was only observable from latitudes South of about 22° North. Saturn was some 6½ months away from opposition (when it would be seen at its best) although its famous ring system now presented a shallow angle to the Earth, causing it to appear considerably dimmer in our night sky than in previous years. For more details on the visibility of this conjunction see the Planetary Conjunctions section below.
At around 10 hours UT on the same day as the Venus-Saturn conjunction, Venus passed 21°.8 North of Fomalhaut ( PsA or Alpha Piscis Austrini, mag. +1.2) a bright blue-white star situated far to the South of the planet in the constellation of Piscis Austrinus, the Southern Fish. Ancient Greek and Babylonian mythology describes it as being the parent of the much more famous zodiacal Pisces and it was envisaged as drinking the water poured from the Waterman's amphora. From the mid-Northern hemisphere it shines in splendid isolation, never far from the Southern horizon, being the brightest star for some distance around it.
Following their conjunction, Venus was now pulling away ENEwards from Saturn. Taken at midnight UT, Saturn was 1°.2 to the South-west of Venus on March 23rd, 2°.3 to the WSW of Venus on March 24th and 3°.4 to the WSW of Venus on March 25th.
Venus passed just 22' (0°.36) South of the star Aqr (Phi Aquarii, mag. +4.2) at 2154 UT on March 25th. On older star maps it is one of several stars which marked the stream of water which flowed from the Waterman's amphora, although more recent maps have shown it marking the top of his amphora. Phi Aquarii is another star which the planet will occult at a future date - in this case during the course of its 2028 evening apparition.
From March 26th through to April 1st, Venus was positioned several degrees South of the asterism known as the Circlet of Pisces, located at the Western end of Pisces, the Fishes. At this time of year it is only visible for a short period ahead of sunrise from latitudes South of about 30° North. The Circlet comprises six stars of fourth and fifth magnitude, although under twilit or light-polluted conditions it is likely that some or all of them will not be seen with the naked-eye. Passage of the Circlet began at 14 hours UT on the 26th when Venus passed 9°.3 South of Psc (Gamma Piscium, mag. +3.7), at the Western end of the Circlet. In 2021 an exoplanet was confirmed as orbiting around Psc. Gamma Piscium b is a gas giant 135 light years distant, equivalent to 1.3 Jupiter masses, taking 1½. years to orbit its parent star at a distance of 1.3 AU.
Another star in the water stream is 1 Aqr (Psi-1 Aquarii, mag. +4.2). In 2003 it too was discovered to have an exoplanet, designated Psi-1 Aquarii b (also 91 Aquarii b and HD 219449 b). Believed to have a mass equivalent to 3.2 times that of Jupiter, it is 144 light years distant and orbits its parent star at a distance of 0.7 AU in a period of 181 days. Venus passed 2°.8 North of Psi-1 Aquarii at 0620 UT on March 26th.
Saturn was located 4°.5 to the WSW of Venus at midnight UT on March 26th and 5°.6 to the WSW of Venus at midnight UT on March 27th.
2 0 2 4 April |
Venus entered Pisces at 1043 UT on April 1st. At 03 hours UT on the same day the planet passed 6°.5 South of TX Psc or 19 Psc (19 Piscium, mag. +5.1v), positioned at the Eastern end of the Circlet and thereby completing its passage of the asterism. TX Psc is a red giant variable star with a small irregular brightness variation of between magnitudes +4.8 and +5.2.
In the first half of April telescopes pointed towards Venus showed a small disk a little over 10" across with a phase of around 98% - so slightly gibbous that the planet almost appeared 'full'.
On April 3rd Venus passed 17' (0°.28) to the South of the planet Neptune (mag. +8.0) in a planetary conjunction which was too close to the Sun for the latter planet to be observed. Neptune would emerge into the dawn twilight over the coming week, at the start of its 2024-25 apparition.
On April 4th Venus passed 8°.4 South of Psc (Omega Piscium, mag. +4.0), which is located a short distance East of the Southern Fish's head.
At 22 hours UT on April 6th a planetary grouping of Venus, Neptune, Saturn and Mars was seen just before dawn from Western Australia and Indonesia; the crescent Moon was also in the vicinity. The planets were spread along 20°.5 in celestial longitude and only 0°.1 in celestial latitude from Aquarius to Pisces, with the Circlet of Pisces to their North. At magnitude +7.9, difficult Neptune required both darkness and optical aid to be seen, whilst Venus rose in twilight, the result being that the five celestial bodies could not be seen simultaneously on this occasion. The 'ideal' latitude to observe the grouping (i.e. where they formed the steepest angle to the local horizon) was about 26°.5 South.
Venus crossed the celestial equator and entered the Northern celestial hemisphere on April 7th, positioned to the ESE of the Circlet. Like in the previous November, the planet was again seen rising due East, but this time only from latitudes South of the mid-Northern hemisphere.
Also on April 7th, from around 14 hours UT, the 28-day old waning crescent Moon passed in front of Venus in the second lunar occultation of the planet's morning apparition. The event was visible in twilight/darkness from the central Pacific Ocean (North-eastern French Polynesia). Further details of this event can be found by following the link in the 'Moon near Venus Dates' section below. Neptune (mag. +7.9) began to emerge into the dawn sky around this time, positioned some 5° to the WSW of Venus.
Following the lunar occultation, the thin crescent Moon continued ENEwards, and from around 1630 UT on April 8th observers sited along a narrow track stretching from Mexico through North America witnessed the New Moon pass in front of the Sun in a total solar eclipse. At the moment of totality Venus was positioned 15°.1 to the WSW of the Sun and was closing in on it, now only weeks away from ending its morning apparition. Mercury, meanwhile, was positioned on the opposite side of the Sun, some 6° to its North-east, having recently ended its first evening apparition of 2024. The totality stage of a total solar eclipse is the only occasion in which both morning and evening planets can be seen in the sky simultaneously.
By the time Venus' solar elongation fell below 15º on April 9th, the planet was again rising in twilight across the inhabited world. Mid-Southern hemisphere observers were still able to see the planet rising an hour before the Sun, although it attained just 8° in altitude at 30 minutes before sunrise.
Mars and Saturn met in conjunction in North-eastern Aquarius at 03 hours UT on April 11th, positioned 22°.5 to the South-west of Venus.
On April 10th Venus briefly exited Pisces and entered the non-zodiacal constellation of Cetus, the Whale, clipping its North-western corner. Venus spent just three days there before re-entering Pisces on April 13th.
At 2246 UT on April 18th Mercury (mag. +3.3), about to begin its second morning apparition of 2024, passed 1°.9 to the North of Venus in a planetary conjunction which, at a solar elongation of only 12°, was too dim and too close to the Sun to be comfortably viewed. Mercury would become visible at dawn over the next few days.
Observers at Northern Tropical latitudes lost sight of Venus from around the third week of April, the planet disappearing into the bright Eastern horizon. Now, only Equatorial and Southern hemisphere latitudes were still able to observe the 'Morning Star', very low down in the ENE at dawn.
The planet entered Aries, the Ram, at the close of the month on April 30th, at which time the planet's solar elongation fell below 10° and it became lost from view from the Northern hemisphere.
2 0 2 4 May - June |
By the middle of May, Venus had become lost from view from Southern latitudes, bringing the planet's 2023-24 morning apparition to a formal close. As it headed into the dawn twilight the planet was speeding ENEwards against the background stars of central Southern Aries at a rate of 1°.24 per day. The planet passed unseen into Taurus, the Bull, on May 18th.
Venus reached superior conjunction (passing behind the Sun as seen from the Earth) in Northern central Taurus on June 4th, positioned at a very distant 1.7329 AU from the Earth (259.2 million kms or 161.1 million statute miles).
Having passed from the morning to the evening sky, Venus remained out of view - lost in the solar glare - for about a month, as it made its slow passage on the far side of its orbit from the Earth. The planet became visible once again from around late June 2024, when it was seen shortly after sunset from Equatorial latitudes as an 'Evening Star' in the WNW, heralding a new evening apparition (2024-25) which lasts through to March 2025.
[Terms in yellow italics are explained in greater detail in an associated article describing planetary movements in the night sky.]
Venus Conjunctions with other Planets: Morning Apparition, 2023-2024
There were two observable planetary conjunctions involving Venus during its 2023-24 morning apparition, both of which favoured Southern hemisphere observers. A conjunction between Venus and Mars took place on February 22nd 2024, Venus passing 38' (0°.63) to the North of the Red Planet in Western Capricornus. At the moment of conjunction Venus was moving against the background stars at a rate of 1°.2 per day whilst Mars was moving at only 0°.8 per day. At 30° North the pair rose in twilight 1¼ hours before the Sun, attaining an altitude of just 8° above the ESE horizon when Mars disappeared from view, whilst at 20° North they rose 1½ hours before sunrise, reaching 13° high in the ESE at the Red Planet's disappearance. From the Equator they rose 1¾ hours before sunrise and reached 18° high in the ESE. Southern Tropical latitudes had the best view; from here they rose two hours before the Sun and reached 20° high in the ESE at Mars' disappearance. From latitudes 35° South and 45° South the pair rose a little over 2 hours before sunrise, reaching 19° and 18° above the Eastern horizon, respectively. Through the telescope, Venus appeared 11".3 in apparent diameter - over 2½ times larger than Mars.
A close conjunction between Venus and Saturn on March 22nd 2024 took place precisely a month after the Venus-Mars conjunction described above. It was a challenging one to the naked-eye observer since it took place at a solar elongations of only 19°. It was only observable from South of the Northern Tropics, the pair at best rising about 1½ hours before the Sun and reaching only 13° high in the Eastern sky at Saturn's disappearance. They were seen in continuous twilight North of about latitude 5° North. The narrow separation between them (20' or 0°.33) was less than the apparent diameter of the Full Moon, allowing them to be fitted within the field-of-view of a telescope eyepiece at low or medium power. At 15".6 in apparent diameter, Saturn's globe appeared one-third larger than that of Venus, its nearly edgewise-on rings spanning over three times larger.
The two planetary conjunctions with Venus which were viewable during the 2023-24 morning apparition are summarised in the table below.
Venus conjunctions with other planets during the 2023-24 morning apparition Note that no planetary conjunctions involving Venus took place during the planet's morning apparition in 2023. The column headed 'UT' is the Universal Time (equivalent to GMT) of the conjunction (in hrs : mins). The separation (column 'Sep') is the angular distance between the two planets, measured relative to Venus, e.g. on 2024 Mar 22, Saturn was positioned 0°.3 North of Venus at the time shown. The 'Fav. Hem' column shows the Hemisphere in which the conjunction was best observed. The expression 'Not high N/S lats' indicates that observers at latitudes further North than about 45°N (or further South than about 45°S) will most likely have found the conjunction difficult or impossible to observe because of low altitude and/or bright twilight. In the 'When Visible' column, a distinction is made between Dawn and Morning visibility; the term Dawn refers specifically to the twilight period before sunrise, whilst the term Morning refers to the period before twilight begins (some conjunctions take place in darkness, others do not, depending upon latitude). The 'Con' column shows the constellation in which the planets were positioned at the time of the conjunction. To find the direction in which the conjunctions were seen on any of the dates in the table, note down the constellation in which the planets were located ('Con' column) on the required date and find the constellation's rising direction for your particular latitude in the Rise-Set direction table. The table is extracted from another table showing Venus conjunctions with other planets from 2021 to 2025 on the Venus Conjunctions page. |
Although any given conjunction takes place at a particular instant in time, it is worth pointing out that, because of the planets' relatively slow daily motions, such events are interesting to observe for several days both before and after the actual conjunction date.
There are in fact two methods of defining a planetary conjunction date: one is measured in Right Ascension (i.e. along the celestial equator) and the other is measured along the ecliptic, which is inclined at 23½° to the Earth's equatorial plane (this is due to the tilt of the Earth's axis in space). An animation showing how conjunction dates are determined by each method can be found on the Jupiter-Uranus 2010-11 triple conjunction page. Although conjunctions measured along the ecliptic can be significantly closer, the Right Ascension method is the more commonly used, and it is the one which is adopted here.
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Moon near Venus Dates, September 2023 to April 2024
The Moon is easy to find, and on one or two days in each month, it passes Venus in the sky. Use the following table to see on which dates the Moon passed near the planet during its 2023-24 morning apparition:
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The Moon moves relatively quickly against the background stars in an Eastward direction, at about its own angular width (0º.5) each hour (about 12º.2 per day). Because it is relatively close to the Earth, an effect called parallax causes it to appear in a slightly different position (against the background stars) when seen from any two locations on the globe at any given instant; the further apart the locations, the greater the Moon's apparent displacement against the background stars. Therefore, for any given date and time listed in the table, the Moon will have appeared closer to Venus when seen from some locations than others. For this reason, the dates shown in the table should be used only for general guidance.
Naked-eye Venus: Apparitions, Conjunctions and Elongations
Credits
Copyright Martin J Powell February 2023