Venus, our nearest solar neighbor, lies closest to Earth in terms of distance. Its orbit is nearly circular, keeping Venus close by always.
Mercury follows Mars in the planetary lineup. But Jupiter stands out, reaching its closest approach in 59 years this evening and appearing larger than usual at rare planetary opposition as it rises in the east when Sun sets in west.
Venus
Venus lies so close to Earth that it appears as a shimmering gem in the evening sky, named for the goddess of love and an important motif in human culture and history. Yet closer inspection reveals hellish terrain hot enough to melt lead, thick atmospheric layers blocking out most sunlight, crushing atmospheric pressures, toxic fumes, and scorching temperatures – not exactly an inviting prospect if one ventured there alone without special protection! If that were not the case then one might well die under its intense heat!
On March 23rd to 31st, Venus moves through Gemini and Cancer before entering Leo on the 31st. As she swings away from us, Venus’ disc gradually reduces until at the end of March it was 97% illuminated but only 10 arcseconds wide – perfect viewing conditions from low and mid Northern latitudes where she may reach heights up to 38deg above the ESE horizon half an hour before sunset.
Venus can often cause false sightings at this time of year, particularly in the UK. Due to its close proximity to the horizon at nightfall and visibility from everyday activity such as walking and driving, people out walking or driving after dark often mistakenly see it. Venus’ brilliance has inspired 20th century science fiction writers such as Edgar Rice Burroughs (Pirates of Venus 1934), Arthur C Clarke (Before Eden 1961) and C.S. Lewis (Perelandra 1943).
On November 9th at around 8 hours UT, the Moon passed very closely to Venus, casting its shadow over it to obscure its view – an event known as lunar occultation that can only be seen from certain areas in the Northern Hemisphere: Eastern Greenland, Iceland, Svalbard and extreme Northern Canada (Ellesmere Island).
Mercury
Mercury is the closest planet to Earth in our Solar System, boasting an orbital radius much lower than Venus, Mars and Jupiter – which explains why it appears closer to the Sun when at maximum elongation and thus easier to spot. Indeed, at times of maximum elongation Mercury can appear like a bright star in the evening sky!
Athena is also the closest planet to Venus, Mars and other outer planets due to her small orbital radius, which aligns more often with them than with Venus and Mars which have greater distances from the Sun.
Mercury’s surface has been marred by meteoroids that have left behind deep craters and canyons, some stretching more than a mile deep.
In 2012, the MESSENGER mission discovered what could be water ice in Mercury’s craters at its polar regions, adding another unique aspect to this rocky planet. The finding puts Mercury among an exclusive club of planets analyzed by humans – these include Moon, Mars and Vesta (an asteroid).
Mercury, one of the planets at its smallest and fastest speeds, can best be observed as an evening’star’ in mid to late September to early October, becoming visible to us until it moves into superior conjunction with the Sun – becoming invisibly again until December when its return can be expected.
Binoculars or telescopes can be used to see Mercury during its greatest elongation during the day, though great care must be taken not to block out the Sun’s blinding glare as even momentary glances could cause permanent eye damage. Mercury can also be seen early morning if it rises before sunrise at its highest point before setting before sunrise – becoming visible for several hours until setting several hours before sunrise again in August when located within Taurus constellation.
Mars
At its closest approach to Earth, Venus stands 23.6 million miles away; however, due to the shape of its orbit it may come as close as 160 million miles, meaning Mars may actually come closer than Venus does at any one time.
On May 8th, the Red Planet is currently located several degrees South of the Circlet of Pisces (Gamma Gamma Delta Alpha Piscium), located near the Western edge of Fishes constellation. As a result, its visibility from all corners of the earth increases significantly.
At the end of April, Mars will appear high in the southern sky at dawn for observers residing at lower latitudes, and nearer its setting time on higher northern latitudes. By then, its magnitude 0.8 disc will have grown 6.5 arcseconds wide by time it sets.
On July 31st, Mars will pass 11deg.5 North of Menkar (Cet or Alpha Ceti, mag. +2.5) in Cetus, the Whale constellation. This line-of-sight conjunction may reveal a faint blue companion; however, these stars remain roughly 40 light years apart.
Mars (mag. +0.8) will reach Saturn (mag. +7) for their third conjunction during its 2021-23 apparition at 2207 UTC on August 1. This provides southern latitude observers a great chance to glimpse this beautiful sight – 16″ across and its rings just under one degree apart!
On February 3 at 2330 UT, Mars passed 7deg.5 north of Acrab (1 Sco or Beta-1 Scorpii, combined mag. +3.9), previously known as Graffias. This double is easily visible with larger telescopes thanks to a close companion of less than one arcsecond magnitude which easily can be seen within an arcsecond’s distance from it.
Jupiter
Astronomers have taken advantage of Jupiter’s proximity to share stunning images. The James Webb Space Telescope has captured atmospheric phenomena often found near its polar regions such as aurorae caused by solar particles colliding with Jupiter’s magnetic field.
Jupiter will appear larger and brighter than ever as it reaches opposition – the point in its orbit when it appears directly opposite Earth from us. You’ll be able to spot it rising from the east in the evening sky before setting in the west at bedtime. While naked-eye viewing may provide enough detail for identification purposes, binoculars or telescopes will provide more comprehensive views of its bands and the Great Red Spot against glowing clouds.
Jupiter rises at 7:21 p.m. local time and travels across the southern sky before setting approximately 12 hours later, offering great viewing conditions if you can see details like its striped bands or even moons! This time is especially good to catch Jupiter since its brightness might allow you to detect details like its stripes or even identify distant moons!
Jupiter, the largest planet in our solar system, is well known for its dazzling appearance and Great Red Spot storm that has existed since 1831. But Jupiter offers more than just eye candy; the planet contains an elaborate network of rings, while its huge magnetic field can trigger auroras on some of its moons.
You might get lucky this week and witness an event known as lunar occultation whereby the Moon briefly passes in front of Jupiter at night, temporarily blocking its view for a brief period. Although only visible from certain regions around the world, three such lunar occultations events will occur during 2023 (please refer to table for details).
NASA provides detailed instructions on how to observe Jupiter’s opposition and occultation this year, including mobile constellation maps that help stargazers pinpoint optimal viewing locations and times.