Jupiter is rapidly losing ground to the evening twilight, appearing 29° above the southwest horizon under deep twilight conditions at the start of the month, but reaching only 12° above the western horizon by the time we reach the end of the month.

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Through the eyepiece of a telescope, Jupiter’s low altitude will mean it will be badly affected by seeing.

This causes fine detail to wobble and blur, making such detail difficult to see well.

On a more encouraging note, Jupiter’s declination is increasing and when next at opposition in early November, it will be able to reach an altitude of 50° in a dark sky.

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Jupiter’s four bright Galilean moons appear in a line, shining like stars near to the planet
Jupiter’s four bright Galilean moons appear in a line, shining like stars near to the planet. Credit: Pete Lawrence

A small telescope will currently show the planet’s disc, two main belts and, for apertures above 100mm, the persistent atmospheric feature known as the Great Red Spot.

The four Galilean moons are another amazing sight to watch as their starlike dots appear to dance endlessly around the planet.

As the end of February approaches and we move into the start of March, mag. –1.9 Jupiter will appear really close to mag. –3.9 Venus, the two planets forming an impressive pair above the western horizon even despite their low altitude.

On 28 February they will appear 1.5° apart, a prelude to their closest separation of just 0.6° on 1 March.

Jupiter, Venus and a thin Moon will appear close to one another at the end of February 2023. Credit: Pete Lawrence
Jupiter, Venus and a thin Moon will appear close to one another at the end of February 2023. Credit: Pete Lawrence

If you have several clear evenings, watching a planetary conjunction involving two bright planets is fascinating.

The rapid positional shifts really give you a sense of the three-dimensional nature of our Solar System.

On the evening of 22 February, a thin 8%-lit waxing crescent Moon sits south of the imaginary line joining Venus to Jupiter, a particularly striking display and a great scene to photograph if the conditions are clear.

How to see the planets in February 2023

The phase and relative sizes of the planets in February 2023. Each planet is shown with south at the top, to show its orientation through a telescope.
The phase and relative sizes of the planets in February 2023. Each planet is shown with south at the top, to show its orientation through a telescope.

Jupiter

  • Best time to see: 1 February, from 17:30 UT
  • Altitude: 34°
  • Location: Pisces
  • Direction: South-southwest
  • Features: Complex atmosphere, Galilean moons
  • Recommended equipment: 75mm or larger

Mercury

  • Best time to see: 1 February, 40 minutes before sunrise
  • Altitude: 3.3° (very low)
  • Location: Sagittarius
  • Direction: Southeast

Having reached greatest western elongation on 30 January, Mercury is a low morning object this month. Its altitude before sunrise is dropping and despite being around mag. 0.0 for the first half of February, brightening to –0.5 by the end of the month, Mercury is unlikely to be seen.

Venus

  • Best time to see: 28 February, 1 hour after sunset
  • Altitude: 16°
  • Location: Pisces
  • Direction: West-southwest

Evening object setting two hours and 15 minutes after sunset at the start of February. Shining at mag. –3.8 on 1 February, if the sky is clear after sunset, it’ll be hard to miss. Very close to Neptune on the evenings of 14 and 15 February. From the UK, the separation on 14 February is 50.2 arcminutes, reducing to 21.8 arcminutes on 15 February.

On the evening of 22 February, mag. –3.9 Venus sits 7.5° from mag. –2.0 Jupiter, a slender 8%-lit waxing crescent Moon also joining the party. By the end of the month, its separation from Jupiter reduces to 1.5°.

Mars

  • Best time to see: 1 February, 20:00 UT
  • Altitude: 62°
  • Location: Taurus
  • Direction: South

Mars is moving away from Earth and consequently is dimming and shrinking through the eyepiece. On 1 February, mag. –0.2 Mars appears 10 arcseconds across. By 28 February, its magnitude drops to +0.4 and its apparent diameter to 8 arcseconds. It remains in Taurus all month.

Saturn

Saturn is in conjunction with the Sun on 16 February and is not visible this month.

Uranus

  • Best time to see: 1 February, from 17:30 UT
  • Altitude: 52°
  • Location: Aries
  • Direction: Just west of south

An evening planet, no longer visible at its highest position under astronomically dark skies. On 1 February, true darkness sees Uranus at an altitude of 52°, only a fraction below its best, but by the end of the month, its altitude will have dropped to 38° before this condition is met.

Uranus shines around mag. +5.8 and requires binoculars to see convincingly. The southern limb of the Moon is around 4 arcminutes from Uranus under daylight conditions at 11:45 UT on 25 February.

Neptune

  • Best time to see: 1 February, from 18:50 UT
  • Altitude: 16°
  • Location: Aquarius
  • Direction: West-southwest

The observing window closes on Neptune this month, the dim planet being just 16° up as true darkness falls at the start of February, but unable to be seen against dark skies from 22 February onwards.

As Venus rushes towards its close encounter with Jupiter at the end of the month, it will also make a harder-to-see close pass of Neptune, visible on the evenings of 14 and 15 February.

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This guide originally appeared in the February 2023 issue of BBC Sky at Night Magazine.

Authors

Pete Lawrence, astronomer and BBC The Sky at Night presenter.
Pete LawrenceAstronomer and presenter

Pete Lawrence is an experienced astronomer and astrophotographer, and a presenter on BBC's The Sky at Night.