RFO

What's Up in the Night Sky

Here's a month-by-month listing of astronomical predictions for the year, compiled by
Jack Welch, RFO astronomy instructor.

 

Abbreviations

Astr Twi/AT -Astronomical Twilight
Cal - Callisto
Civ Twi/CT - Civil Twilight
Cr - Crescent
Disap - Disappear
Dbl Tr - Double Tansit
E - End/Exit
Ec/Ecl - Eclipse
EcD - Eclipse disappearance
EcR - Eclipse reappearance
Eur - Europa
Ex - Exit
Gan - Ganymede
Gr El - Greatest Elongation
Jup - Jupiter
Lun - Lunar
Max - Maximum
Mer - Mercury
Min - Minimum
Mn - Moon
Naut Twi/NT - Nautical Twilight
Nr - Near
Occ - Occultation
OcD - Occultation disappearance
OcR - Occultation reapparance
Opp - Opposition
Pen - Penumbral
Reap - Reappear
Qtr - Quarter
Sat - Saturn /Satellite
Sh - Shadow
S/St - Start
Stat - Stationary
Tot - Total
Tr - Transit
V Nr - Very Near
Ven - Venus
Zod Lt - Zodiacal Light

 

Observing

Upcoming Observing Highlights

August 2018
  • Friday, 8/3/2018 - Gan OcD - Time: 22:30
    • Ganymede disappears behind Jupiter's south polar region at 2245.
  • Saturday, 8/4/2018 - Occ of xi-2 Cet - Time: 02:30
    • At about 0231 the mag 4.3 star xi-2 Ceti will reappear from behind the moon's dark limb at axis angle 308° (or 53° from the north cusp). (Calculated using Occult4 for the RFO site. Details will differ as distance from RFO increases.)
  • Saturday, 8/4/2018 - Last Qtr - Time: 11:30
    • -
  • Sunday, 8/5/2018 - Eur Tr - Time: 22:00
    • Europa begins transiting Jupiter at 2223. Jupiter sets with the transit in progress.
  • Monday, 8/6/2018 - Mn nr Aldebaran - Time: 05:30
    • The moon is near the bright red-orange star Aldebaran.
  • Monday, 8/6/2018 - Io OcD - Time: 22:00
    • Io disappears behind Jupiter at 2210.
  • Tuesday, 8/7/2018 - Ura stat - Time: 14:00
    • Uranus begins retrograde motion in Aries.
  • Tuesday, 8/7/2018 - Io Sat/Sh Tr & Eur EcR - Time: 20:30
    • Io's transit of Jupiter, in progress at sunset, ends at 2138. Io's shadow transits from 2044 to 2253. At 2202 Europa reappears from Jupiter's shadow 0.8 Jupiter diameter east of Jupiter.
  • Saturday, 8/11/2018 - Large Tides thru 8/13 - Time: 00:00
    • Large tides due to the new moon 16 hours after perigee.
  • Saturday, 8/11/2018 - New Moon - Time: 03:00
    • -
  • Sunday, 8/12/2018 - 4.5% CrMn - Time: 08:30
    • Look for a thin crescent moon in the west after sunset.
  • Sunday, 8/12/2018 - Perseids Peak - Time: 19:00
    • The peak of the Perseid Meteor Shower is expected sometime between about 1pm 8/12 and 1am 8/13, but this shower remains active for many days before and after peak. Over 100 meteors per hour are typical at the peak. The Perseids become viewable after about 11pm and are best during the a.m. hours. Conditions are ideal this year with no moonlight interference.
  • Tuesday, 8/14/2018 - Dbl Sh Tr & Eur OcR/EcD - Time: 21:00
    • Timings of these Jupiter events:
      2124 Io begins transit
      2152 Ganymede's shadow begins transit of north polar region ("above" Io)
      2208 Europa emerges from behind Jupiter's SE limb
      2220 Europa disappears into Jupiter's shadow
      2239 Io's shadow transit begins - Start of Dbl Sh Tr
      Note that Jupiter's altitude will be 10° (calculated for RFO site) by 2239.
  • Wednesday, 8/15/2018 - Io EcR - Time: 22:00
    • Io reappears from Jupiter's shadow 0.5 Jupiter diameter east of Jupiter at 2204.
  • Thursday, 8/16/2018 - Mn nr Jup - Time: 21:30
    • -
  • Saturday, 8/18/2018 - 1st Qtr - Time: 01:00
    • -
  • Monday, 8/20/2018 - Mer in E thru 9/5 - Time: 05:30
    • Mercury provides a good morning apparition from about 8/20 to 9/5 reaching a maximum altitude 45 minutes before sunrise of 8° on 8/27 & 8/28.
  • Monday, 8/20/2018 - Mn vnr Sat - Time: 24:00
    • -
  • Tuesday, 8/21/2018 - Gan Tr & Eur OcD - Time: 20:30
    • Ganymede transits Jupiter's north polar region from 2040 (nautical twilight at RFO) to 2244. At 2225 Europa disappears into Jupiter's shadow. Note that Jupiter's altitude will only be 5° by 2244 (calculated for RFO site).
  • Thursday, 8/23/2018 - Dbl Sat Tr of Jup - Time: 20:30
    • In progress at sunset, Io's shadow transit ends at 2111 and Europa's shadow transit ends at 2151.
  • Sunday, 8/26/2018 - "Sturgeon" Moon - Time: 05:00
    • -
  • Thursday, 8/30/2018 - Dbl Sat Tr & Sh Tr - Time: 20:00
    • Io and Europa are in transit of Jupiter at sunset. At 2057 Io's shadow transit begins. Io's transit ends at 2156. Europa's transit ends at 2205. Europa's shadow begins transit at 2212, starting a double shadow transit, though Jupiter will be very low in the west by this time.
  • Friday, 8/31/2018 - Io EcR - Time: 20:00
    • Io reappears from Jupiter's shadow 0.5 Jupiter diameter east of Jupiter at 2023 (nautical twilight at RFO).

September 2018
  • Saturday, 9/1/2018 - Mer in E thru 9/5 - Time: 05:30
    • Mercury concludes a good morning apparition during the first few days of this month.
  • Saturday, 9/1/2018 - Ven vnr Spica - Time: 20:30
    • Venus is very near the bright star Spica in Virgo (use binoculars), about 8° high in the SW 45 minutes after sunset. Do not confuse Venus with Jupiter, which is higher and further south.
  • Sunday, 9/2/2018 - Last Qtr - Time: 19:30
    • -
  • Monday, 9/3/2018 - Mn nr Aldebaran - Time: 01:00
    • The moon is near the bright red-orange star Aldebaran. Use binoculars.
  • Thursday, 9/6/2018 - Sat stat - Time: 03:00
    • Saturn ends retrograde motion in Sagittarius.
  • Friday, 9/7/2018 - Nep opp - Time: 11:00
    • Neptune is at opposition in Aquarius at mag 7.8 and a disk size of 2.3". Located about 70% of the way from lambda Aqr to phi Aqr, use a finder's chart for the exact position.
  • Saturday, 9/8/2018 - Zod Light in E thru 9/21 - Time: 04:30
    • The Zodiacal Light is visible in the east (at a dark site) between between about 0430 and 0515 (15 minutes later by 9/21).
  • Sunday, 9/9/2018 - New Moon - Time: 11:00
    • -
  • Monday, 9/10/2018 - 2.8% CrMn - Time: 19:30
    • Look for an ultra-thin crescent moon 6° high 13° south of due west 30 minutes after sunset (or at 1956 calculated for the RFO site). Use binoculars.
  • Thursday, 9/13/2018 - Mn nr Jup - Time: 20:00
    • -
  • Friday, 9/14/2018 - Occ of 49 Lib - Time: 21:00
    • At about 2118 the mag 5.5 star 49 Librae disappears behind the moon's dark limb 51° from the north cusp. (Calculated using Occult4 for the RFO site. Details will differ as distance from RFO increases.)
  • Sunday, 9/16/2018 - 1st Qtr - Time: 16:00
    • -
  • Wednesday, 9/19/2018 - Mn nr Mar - Time: 23:30
    • -
  • Friday, 9/21/2018 - Ven brightest - Time: 03:00
    • Venus reaches magnitude -4.8.
  • Saturday, 9/22/2018 - Autumnal Equinox - Time: 19:00
    • The equinox occurs at 1854.
  • Monday, 9/24/2018 - "Harvest" Moon - Time: 20:00
    • -
  • Sunday, 9/30/2018 - Mn vnr Aldebaran - Time: 01:00
    • The moon is very near the bright red-orange star Aldebaran. Use binoculars.

October 2018
  • Tuesday, 10/2/2018 - Last Qtr - Time: 02:30
    • -
  • Monday, 10/8/2018 - Zod Light in E thru 10/21 - Time: 05:00
    • The Zodiacal Light is visible in the east (at a dark site) between between about 0500 and 0545 (15 minutes later by 10/21).
  • Monday, 10/8/2018 - New Moon - Time: 21:00
    • -
  • Tuesday, 10/9/2018 - 1.3% CrMn - Time: 19:00
    • Look for the ultra-thin crescent moon 5° high 13° south of due west 20 minutes after sunset (or at 1901 calculated for the RFO site). Use binoculars.
  • Wednesday, 10/10/2018 - 4.8% CrMn - Time: 19:00
    • Look for the thin crescent moon 10° high 30 minutes after sunset.
  • Thursday, 10/11/2018 - CrMn nr Jup - Time: 19:00
    • -
  • Friday, 10/12/2018 - Algol min - Time: 06:00
    • Algol eclipse minimum is at 0603.
  • Sunday, 10/14/2018 - Occ of 14 Sgr - Time: 19:00
    • At about 1928 the mag 5.5 star 14 Sagittarii disappears behind the moon's dark limb 86° from the north cusp. (Calculated using Occult4 for the RFO site. Details will differ as distance from RFO increases.)
  • Sunday, 10/14/2018 - CrMn Vnr Sat - Time: 20:00
    • -
  • Monday, 10/15/2018 - Algol min - Time: 03:00
    • Algol elcipse minimum is at 0252.
  • Monday, 10/15/2018 - Occ of omicron Sgr - Time: 18:00
    • At about 1824 (daylight at RFO) the mag 3.8 star omicron Sagittarii disappears behind the moon's dark limb 52° from the north cusp. Then, at about 1937 the star reappears from behind the bright limb at axis angle 314° (or 47° from the north cusp). This reappearance event is challenging and requires larger aperture scopes. Tracking scopes can continue from disappearance to capture the reappearance. (Calculated using Occult4 for the RFO site. Details will differ as distance from RFO increases.)
  • Tuesday, 10/16/2018 - 1st Qtr - Time: 11:00
    • -
  • Wednesday, 10/17/2018 - Algol min - Time: 23:30
    • Algol eclipse minimum is at 2341.
  • Wednesday, 10/17/2018 - Mn nr Mar - Time: 23:30
    • -
  • Thursday, 10/18/2018 - Occ of Nashira - Time: 21:30
    • At about 2145 the mag 3.7 star Nashira (gamma Capricorni) disappears behind the moon's dark limb 45° from the south cusp. (Calculated using Occult4 for the RFO site. Details will differ as distance from RFO increases.)
  • Saturday, 10/20/2018 - Algol min - Time: 20:30
    • Algol eclipse minimum is at 2030.
  • Saturday, 10/20/2018 - Occ of psi-1&2 Aqr - Time: 22:00
    • At about 2208 the mag 4.2 star psi-1 Aquarii disappears behind the moon's dark limb 51° from the north cusp. Then, at 2318 the mag 4.4 star psi-2 Aquarii disappears behind the moon's dark limb 47° from the south cusp. Psi-2 Aqr is an extremely close equal double so may be observable as such for those with suitable equipment. (Calculated using Occult4 for the RFO site. Details will differ as distance from RFO increases.)
  • Tuesday, 10/23/2018 - Ura opp - Time: 18:00
    • Uranus is at opposition in Aries, reaching magnitude 5.7 and a disk size of 3.7". This bright cyan colored planet will be about 2.5° NE of omicron Piscium.
  • Wednesday, 10/24/2018 - "Hunter's" Moon - Time: 09:30
    • -
  • Friday, 10/26/2018 - Ven IC - Time: 07:00
    • Venus is at inferior conjunction (between the earth and sun).
  • Saturday, 10/27/2018 - Mn Vnr Aldebaran - Time: 06:00
    • The moon is VERY near the bright red-orange star Aldebaran in Taurus. Use binoculars to appreciate the color.
  • Tuesday, 10/30/2018 - Occ of 56 Gem - Time: 00:30
    • At about 0033 the mag 5.1 star 56 Geminorum reappears from behind the moon's dark limb at axis angle 225° (or 46° from the south cusp). (Calculated using Occult4 for the RFO site. Details will differ as distance from RFO increases.)
  • Wednesday, 10/31/2018 - Last Qtr - Time: 09:30
    • -

November 2018
  • Sunday, 11/4/2018 - DST ends - Time: 02:00
    • -
  • Sunday, 11/4/2018 - Algol min - Time: 03:30
    • Algol eclipse minimum is at 0335.
  • Wednesday, 11/7/2018 - Algol min - Time: 00:30
    • Algol eclipse minimum is at 0024.
  • Wednesday, 11/7/2018 - New Moon - Time: 08:00
    • -
  • Thursday, 11/8/2018 - 2.2% CrMn - Time: 17:30
    • Look for the very thin crescent moon 6° high 28° south of due west 30 minutes after sunset (or at 1733 calculated for the RFO site).
  • Friday, 11/9/2018 - 6% CrMn - Time: 17:30
    • -
  • Friday, 11/9/2018 - Algol min - Time: 21:00
    • Algol eclipse minimum is at 2113.
  • Monday, 11/12/2018 - Algol min - Time: 18:00
    • Algol eclipse minimum is at 1802.
  • Wednesday, 11/14/2018 - Occ of 30 Cap - Time: 17:00
    • At about 1723 the mag 5.4 star 30 Capricorni disappears behind the moon's dark limb 63° from the north cusp. 30 Cap is an extremely close equal double so may be observable as such for those with suitable equipment. (Calculated using Occult4 for the RFO site. Details will differ as distance from RFO increases.)
  • Thursday, 11/15/2018 - 1st Qtr - Time: 07:00
    • -
  • Thursday, 11/15/2018 - Mn Vnr Mar - Time: 20:00
    • -
  • Saturday, 11/17/2018 - Juno opp - Time: 14:00
    • The minor planet Juno is at opposition in Eridanus, reaching magnitude 7.4. RA/Dec: 3h53.9m/-3°20'.
  • Saturday, 11/17/2018 - Leonids Peak - Time: 14:30
    • Conditions are fairly favorable for viewing the Leonid meteors after the moon sets around 1am on the morning of 11/17 and after 2am on 11/18. The activity is expected to be low this year, around 10 per hour, but one never knows.
  • Thursday, 11/22/2018 - "Beaver" Moon - Time: 21:30
    • -
  • Friday, 11/23/2018 - Mn nr Aldebaran - Time: 19:00
    • The moon is near the bright red-orange star Aldebaran.
  • Saturday, 11/24/2018 - Algol min - Time: 05:30
    • Algol eclipse minimum is at 0518.
  • Saturday, 11/24/2018 - Occ of chi-1 Ori - Time: 20:00
    • At about 2001 the mag 4.4 star chi-1 Orionis reappears from behind the moon's dark limb at axis angle 227° (or 72° from the south cusp). (Calculated using Occult4 for the RFO site. Details will differ as distance from RFO increases.)
  • Saturday, 11/24/2018 - Nep stat - Time: 24:00
    • Neptune ends retrograde motion.
  • Tuesday, 11/27/2018 - Algol min - Time: 02:00
    • Algol eclipse minimum is at 0207.
  • Thursday, 11/29/2018 - Last Qtr - Time: 16:30
    • -
  • Thursday, 11/29/2018 - Algol min - Time: 23:00
    • Algol eclipse minimum is at 2256.

December 2018
  • Saturday, 12/1/2018 - Ven brightest - Time: 24:00
    • -
  • Sunday, 12/2/2018 - Algol min - Time: 19:30
    • Algol eclipse minimum is at 1945.
  • Monday, 12/3/2018 - CrMn nr Ven - Time: 05:30
    • -
  • Tuesday, 12/4/2018 - Mer in E thru 12/30 - Time: 06:30
    • Mercury has a moderately good apparition, reaching a maximum altitude 45 minutes before sunrise of 10° on 12/14. Mercury will be very near the bright star Graffias on the mornings of 12/15 and 12/16 (use binoculars).
  • Thursday, 12/6/2018 - Mar Vnr Nep - Time: 19:00
    • Mars is VERY near the much dimmer and smaller Neptune.
  • Thursday, 12/6/2018 - New Moon - Time: 23:30
    • -
  • Friday, 12/7/2018 - Mar Vnr Nep - Time: 19:00
    • Mars is VERY near the much dimmer and smaller Neptune.
  • Saturday, 12/8/2018 - 2.9% CrMn - Time: 17:00
    • Look for a very thin crescent moon 9° high in the southwest 30 minutes after sunset.
  • Friday, 12/14/2018 - Geminids Peak - Time: 04:30
    • Conditions are VERY favorable for the Geminid meteor shower. A crescent moon sets around 11pm on 12/13 leaving a dark sky for these bright meteors. About 120 meteors per hour are typical at peak.
  • Friday, 12/14/2018 - Mn nr Mar - Time: 19:00
    • -
  • Saturday, 12/15/2018 - 1st Qtr - Time: 04:00
    • -
  • Monday, 12/17/2018 - Algol min - Time: 04:00
    • Algol eclipse minimum is at 0350.
  • Wednesday, 12/19/2018 - Occ of mu Cet - Time: 00:30
    • At about 0044 the mag 4.3 star mu Ceti disappears behind the moon's dark limb 21° from the south cusp. Mu Cet is an extremely close multiple so may be observable as such for those with suitable equipment. (Calculated using Occult4 for the RFO site. Details will differ as distance from RFO increases.)
  • Thursday, 12/20/2018 - Algol min - Time: 00:30
    • Algol eclipse minimum is at 0039.
  • Thursday, 12/20/2018 - Mn vnr Aldebaran - Time: 24:00
    • The moon is very near the bright red-orange star Aldebaran in Taurus. Use binoculars to appreciate the color.
  • Friday, 12/21/2018 - Jup Vnr Mer - Time: 06:30
    • Jupiter, emerging into the morning sky since about mid-month, passes VERY near Mercury this morning. While Jupiter is the brighter of the two, much smaller Mercury has greater surface brightness. Use binoculars or the lowest magnification scope eyepiece.
  • Friday, 12/21/2018 - Winter Solstice - Time: 14:30
    • The winter solstice is at 1423.
  • Saturday, 12/22/2018 - "Cold" Moon - Time: 10:00
    • -
  • Saturday, 12/22/2018 - Algol min - Time: 21:30
    • Algol eclipse minimum is at 2128.
  • Tuesday, 12/25/2018 - Algol min - Time: 18:30
    • Algol eclipse minimum is at 1817.
  • Saturday, 12/29/2018 - Last Qtr - Time: 01:30
    • -

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