December 2022 – What’s Up!

Week of 26th December

  • Astronomical twilight ends at 18:07 GMT at the beginning of the week and at 18:12 GMT by the end of the week.
  • Mercury (mag -0.1) will be at its highest point above our horizon on Monday evening, when it will reach an altitude of 9°. Look just after sunset in the southwest, where you will also find Venus (-3.9).
  • Catch Saturn (+0.8) before it is too late… the planet is ever lower to the western horizon in the early evening, setting at around 20:00 GMT. By the end of January it will no longer be visible in our evening sky.
  • Jupiter (-2.4) is still well placed in the early evening, setting at around 23:40 GMT and Mars (-1.3) is increasing in altitude, though dropping in apparent size (now about 15 arcseconds) following its opposition.
  • On Sunday, the Waxing Gibbous Moon will graze the planet Uranus (+5.7). Look between about 22:00 and 23:30 GMT to see the celestial alignment. From more northerly latitudes, the event will be an occultation.
  • The Moon is First Quarter on Friday.
  • The Sun currently has six active regions: AR 3168, 3169, 3171, 3172, 3173 & 3175. The sunspot number is 107.
  • There are no visible evening ISS passes this week.

Week of 19th December

  • Astronomical twilight ends at 18:03 GMT at the beginning of the week and at 18:07 GMT by the end of the week.
  • Mercury (mag -0.5) reaches Greatest Eastern Elongation on Wednesday, when it will be at its largest separation from the Sun in our sky. Look low in the south west just after sunset to spot the planet. Venus (-3.9) will be also visible, about 5° further west and closer to the horizon as it climbs higher in our evening sky over the coming weeks.
  • The Winter Solstice is on Wednesday, when the Sun will reach its most southerly point in the sky at a declination of -23.5°, appearing at a maximum altitude of just 15.5° at noon here in Marlborough. This is the shortest day of the year, with just under 8 hours of sunlight in the 24 hour day. Christmas borrows this date from the pagan mid-winter festival, though obviously falls a few days later on the 25th December. Happy Solstice / Christmas to you all!
  • The Ursid meteor shower peaks on Thursday. It is a relatively quiet shower, with a peak ZHR of just 10 meteors. It is caused by debris from comet 8P/Tuttle
  • The Moon is New on Friday.
  • The Sun currently has nine active regions: AR 3160, 3162, 3163, 3165, 3166, 3167, 3168, 3169 & 3170. The sunspot number is 139.
  • There are no visible evening ISS passes this week.

 

Week of 12th December

  • Astronomical twilight ends at 18:02 GMT at the beginning of the week and at 18:03 GMT by the end of the week.
  • The Geminid meteor shower runs from the 4th to 17th December, with its peak around 13:00 GMT on Wednesday. The shower is caused by debris deposited by asteroid 3200 Phaethon. It is one of the finest meteor showers of the year, with a Zenithal Hourly Rate of around 80-100 meteors. The Waning Gibbous Moon means the best observing prospects are before midnight on Tuesday and Wednesday.
  • The planets are wonderful evening objects with Saturn (mag +0.8) furthest west, followed by Jupiter (-2.5) in the south and Mars (-1.7) in the east. Neptune (+7.9) is just to the west of Jupiter and Uranus (+5.7) is about half way between Jupiter and Mars. Get out your binoculars or a telescope and try to find all five.
  • The Moon is Last Quarter on Friday.
  • The Sun currently has seven active regions: AR 3153, 3156, 3157, 3158, 3160, 3161 & 3162. The sunspot number is 111.
  • There are no visible evening ISS passes this week.

Week of 5th December

  • Astronomical twilight ends at 18:02 GMT at the beginning of the week and at 18:02 GMT by the end of the week.
  • There are two lunar occultations this week, the first is on Monday afternoon when Uranus (mag +5.7) will disappear behind the Moon at 16:46 UT and reappear at 17:18 UT. The second is on Thursday morning at 04:57 UT when Mars (-1.9) will be occulted by the Moon, reappearing at 05:59 UT.
  • Mars (-1.9) reaches opposition on Thursday, the point in its orbit when it will appear directly opposite the Sun from Earth. This is the best time to observe the planet as it appears at its brightest and largest in our sky. Its close proximity to Earth also makes this the ideal time to travel to Mars! It won’t be at opposition again until January 2027.
  • The Moon is Full on Thursday – the Cold Moon.
  • The Sun currently has five active regions: AR 3153, 3154, 3155, 3156 & 3157. The sunspot number is 68.
  • There are visible evening ISS passes this week as follows:
    Monday 5th: 16:50 (-2.7) W to SE, max 47° & 18:28 (-0.7) WSW to SSW, max 13°
    Tuesday 6th: 17:39 (-0.9) W to S, max 18°
    Wednesday 7th: 16:50 (-1.4) W to SSE, max 26°
    Friday 9th: 16:51 (-0.4) WSW to SSW, max 13°

 

 

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