March 2021 What’s Up!

Week of 29th March

  • Astronomical twilight ends at 21:33 BST at the beginning of the week and at 21:46 BST by the end of the week
  • As the Moon wanes this week, the evenings give an opportunity for a spot of galaxy hunting. Use binoculars, or better a small telescope, to find Markarian’s Chain – a string of galaxies including M84 (mag +9.0) and M86 (+8.8) on the border of Virgo. Move up to Ursa Major to find Messier 51, The Whirlpool Galaxy (+7.9), about 3° below the end of the Plough’s handle. Two clusters worth seeking out are M3 (+6.2), a globular cluster in Canes Venatici and M44, The Beehive Cluster (+3.1), a wonderful open cluster in Cancer
  • The Moon is Last Quarter on Sunday
  • The Sun has one active region, AR 2812. The sunspot number is 11
  • The ISS makes the following evening passes this week:
    Monday: 20:24, W to ESE, max 86° and 22:01, W to WSW, max 29°
    Tuesday: 21:13, W to SSE, max 44°
    Wednesday: 20:26, W to ESE, max 58° and 22:03, W to SW, max 16°
    Thursday: 21:16, W to S, max 23°
    Friday: 20:28, W to SE, max 32°
    Saturday: 21:19, WSW to SSW, max 11°
    Sunday: 20:30, W to S, max 17°

Week of 22nd March

  • Astronomical twilight ends at 20:18 UT at the beginning of the week and at 21:31 BST by the end of the week
  • British Summer Time starts on Sunday when the clocks ‘spring forwards’ one hour at 01:00 UT to become 02:00 BST
  • A new nova has been observed in Cassiopeia and it has brightened rapidly from mag +9.6 to +7.5, so can be seen in binoculars. It is located about 5° east of the star Caph (Beta Cassiopeiae), the easternmost star of the familiar W asterism in Cassiopeia. Follow a line from Shedar (Alpha Cass.) to Caph and extend it the same distance again out towards the open cluster M52 and you should be able to locate the nova. Follow its progress over the coming weeks as it dims
  • The Moon is Full on Sunday
  • The Sun has one active region, AR 2810. The sunspot number is 12
  • The ISS makes the following evening passes this week:
    Monday: 20:05, WSW to E, max 73° and 21:42, W, max 13°
    Tuesday: 19:18, WSW to E, max 58° and 20:55, W, max 45°
    Wednesday: 20:07, W to E, max 87° and 21:44, W, max 14°
    Thursday: 19:20, WSW to E, max 86° and 20:57, W, max 48°
    Friday: 20:09, W to E, max 86° and 21:46, W, max 14°
    Saturday: 19:22, W to E, max 84° and 20:59, W to WSW, max 43°
    Sunday: 21:11, W to ESE, max 74° and 22:48, W, max 12°

Week of 15th March

  • Astronomical twilight ends at 20:04 UT at the beginning of the week and at 20:16 UT by the end of the week
  • On Friday evening, the waxing crescent Moon will be in conjunction with Mars, separated by just over 2°. The pair will make a fine sight between the Hyades and Pleiades clusters
  • The Vernal or Spring Equinox is on Saturday. At about 09:22 UT the Sun will cross the ecliptic, heading North, it will have a declination of 00° and a Right Ascension of 00h. We will enjoy almost exactly 12 hours of day and 12 hours of night; the Sun will rise from a point on the horizon due East and set at a point due West. The position of the Sun at the Vernal Equinox is also known as the First Point of Aries; however, these days the Sun is in the constellation of Pisces at this time, due to the precession of the Earth’s axis. The Vernal Equinox marks the first day of spring
  • The Moon is First Quarter on Sunday
  • The Sun has one active region, AR 2808. The sunspot number is 12
  • The ISS makes the following evening passes this week:
    Thursday: 20:02, SSW to S, max 18°
    Friday: 19:15, S to ESE, max 16° and 20:51, WSW to SW, max 19°
    Saturday: 20:03, SW to SSE, max 44°
    Sunday: 19:16, SW to E, max 32° and 20:53, WSW to WSW, max 35°

Week of 8th March

  • Astronomical twilight ends at 19:51 UT at the beginning of the week and at 20:02 UT by the end of the week
  • This is the week to attempt the Messier Marathon. It is possible to observe all 110 objects of the famous late 18th Century catalogue compiled by Charles Messier in one night at this time of year. It is best attempted around the New Moon. Stamina is required as the session starts immediately after sunset and continues through till dawn. If you do have a go, can you beat the 96 Messier objects spotted from the MCBO last year? Good luck!
  • The Moon is New on Saturday
  • The Sun has two active regions, AR 2806 and AR 2807. The sunspot number is 23
  • There are no visible evening ISS passes this week

Week of 1st March

  • Astronomical twilight ends at 19:39 UT at the beginning of the week and at 19:49 UT by the end of the week
  • Watch as Mars (mag +1.0) passes between the Pleiades and the Hyades this week. On Thursday it will be closest to the Pleiades, separated by only about 2.5°
  • For the early risers on Friday morning, at around 06:30 UT Jupiter (-2.0) and Mercury (+0.2) will rise together in the southeast. They will be separated by just 19 arc minutes
  • Mercury reaches greatest elongation west on Saturday
  • The Moon is Last Quarter on Saturday
  • After a busy week on the surface of the Sun, there is just one active region (AR 2804) making its way around the off-going limb. The sunspot number is 14
  • There are no visible evening ISS passes this week

 

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