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

February 2016
  • Monday, 2/1/2016 - Eur Sh/Sat Tr - Time: 02:00
    • Europa's shadow will transit Jupiter from 0208 to 0457, and Europa will transit from 0347 to 0631.
  • Monday, 2/1/2016 - Mer in E thru 2/13 - Time: 06:30
    • Mercury provides a fair morning apparition reaching a maximum altitude of 7° 45 minutes before sunrise (or at 0632 at RFO) on 1/31.
  • Wednesday, 2/3/2016 - Eur OcR & Io Sh/Sat Tr - Time: 01:00
    • At 0121 Europa will reappear from behind Jupiter's east limb. Then Io's shadow transits Jupiter from 0128 to 0344, and Io transits from 0214 to 0428.
  • Wednesday, 2/3/2016 - Io EcD - Time: 22:30
    • At 2238 Io will disappear into Jupiter's shadow 0.3 Jupiter disk width west of Jupiter's limb. (Io's OcR is at 0139.)
  • Thursday, 2/4/2016 - Io OcR - Time: 01:30
    • At 0139 Io will reappear from behind Jupiter's east limb.
  • Thursday, 2/4/2016 - Io Sh/Sat Tr - Time: 21:30
    • Jupiter rises at 2027 with Io's shadow in transit, and Io's transit starts moments after Jupiter rises. The shadow transit ends at 2212 and Io's transit ends at 2255.
  • Thursday, 2/4/2016 - Cal Oc - Time: 23:00
    • Callisto will pass behind Jupiter's south polar region, disappearing at 2318 and reappearing at 0104. Start watching around 2230.
  • Friday, 2/5/2016 - Cr Mn nr Ven nr Mer - Time: 06:30
    • The crescent moon, Venus and Mercury lie in a line from top to bottom in the east 45 minutes before sunrise.
  • Saturday, 2/6/2016 - Gan EcD - Time: 02:00
    • At 0203 Ganymede will disappear into Jupiter's shadow 0.7 Jupiter disk width west of Jupiter's limb.
  • Saturday, 2/6/2016 - Cr Mn v nr Mer nr Ven - Time: 06:30
    • The 5% crescent moon is just above Mercury, with Venus to nearby to the south. Look 45 minutes before sunrise (or at 0626 at RFO).
  • Monday, 2/8/2016 - New Moon - Time: 06:30
    • -
  • Tuesday, 2/9/2016 - 3.1% Cr Mn - Time: 18:30
    • An ultra-thin 3.1% crescent moon will be 5° high 13° south of due west 70 minutes after sunset (or at 1851 calculated for the RFO site). Begin looking about 45 minutes after sunset and use binoculars.
  • Tuesday, 2/9/2016 - Eur EcD - Time: 23:30
    • At 2339 Europa will disappear into Jupiter's shadow 0.4 Jupiter disk width west of Jupiter's limb.
  • Wednesday, 2/10/2016 - Io Sh/Sat Tr & Eur OcR - Time: 03:00
    • Io's shadow will transit Jupiter from 0322 to 0538 with Io transiting from 0359 to 0614. In addition, Europa will reappear from behind Jupiter's east limb at 0338.
  • Wednesday, 2/10/2016 - Algol min - Time: 05:30
    • Algol eclipse minimum is at 0523.
  • Wednesday, 2/10/2016 - Io EcD - Time: 23:30
    • At 2332 Io will disappear into Jupiter's shadow 0.7 Jupiter disk width west of Jupiter's limb. (Io will reappear from behind Jupiter's east limb at 0325.)
  • Thursday, 2/11/2016 - Io Sh/Sat Tr - Time: 20:30
    • (Europa and its shadow are in transit when Jupiter rises, with the shadow transit ending before Jupiter reaches a good altitude.)
      Io's shadow transits Jupiter from 2050 to 0006 and Io transits from 2125 to 0040. Europa's transit ends at 2100.
  • Saturday, 2/13/2016 - Cal Sh Tr - Time: 01:00
    • Callisto's shadow transits Jupiter's north polar region from 0108 until 0425.
  • Saturday, 2/13/2016 - Algol min - Time: 02:00
    • Algol eclipse minimum is at 0212.
  • Sunday, 2/14/2016 - 1st Qtr - Time: 24:00
    • -
  • Monday, 2/15/2016 - Occ of 75 Tau - Time: 21:00
    • At about 2115 the magnitude 5.0 star 75 Tauri will disappear behind the moon's dark limb 73° from the north cusp. Calculated using Occult4 for the RFO site. Details will differ as distance from RFO increases.
  • Monday, 2/15/2016 - Occ of ZC677 - Time: 22:00
    • At about 2225 the magnitude 4.8 star ZC677 will disappear behind the moon's dark limb 60° from the south cusp. Calculated using Occult4 for the RFO site. Details will differ as distance from RFO increases.
  • Monday, 2/15/2016 - Algol min - Time: 23:00
    • Algol eclipse minimum is at 2301.
  • Tuesday, 2/16/2016 - Occ of Aldebaran - Time: 01:00
    • At about 0103 the magnitude 0.9 red-orange star Aldebaran (alpha Tauri) will disappear behind the moon's dark limb 60° from the north cusp. The moon will be 10° high 13° north of due west. Calculated using Occult4 for the RFO site. Details will differ as distance from RFO increases.
  • Tuesday, 2/16/2016 - Gan Sh/Sat Tr - Time: 19:30
    • Ganymede's shadow transits Jupiter from 1957 to 2318. Note that Jupiter is only 4° high in the east at 1957. Ganymede transits from 2158 to 0106.
  • Tuesday, 2/16/2016 - Occ of 111 Tau - Time: 20:30
    • At about 2036 the magnitude 5.0 star 111 Tauri will disappear behind the moon's dark limb 34° from the south cusp. Calculated using Occult4 for the RFO site. Details will differ as distance from RFO increases.
  • Wednesday, 2/17/2016 - Eur EcD - Time: 02:00
    • At 0212 Europa will disappear into Jupiter's shadow 0.3 Jupiter disk width west of Jupiter.
  • Thursday, 2/18/2016 - Io EcD - Time: 02:00
    • At 0226 Io will disappear into Jupiter's shadow 0.2 Jupiter disk width west of Jupiter.
  • Thursday, 2/18/2016 - Algol min - Time: 20:00
    • Algol eclipse minimum is at 1950.
  • Thursday, 2/18/2016 - Eur & Io Sh/Sat Tr - Time: 20:30
    • Europa's shadow will transit Jupiter from 2038 to 2327, with Europa transiting from 2132 to 0017.
      Io's shadow will transit from 2343 to 0159, with Io transiting from 0009 to 0224.
  • Friday, 2/19/2016 - Io EcD - Time: 20:30
    • At 2054 Io will disappear into Jupiter's shadow 0.2 Jupiter disk width west of Jupiter's limb. Io will reappear from behind Jupiter's east limb at 2336.
  • Sunday, 2/21/2016 - "Snow" Moon - Time: 10:30
    • -
  • Tuesday, 2/23/2016 - Mn v nr Jup - Time: 20:00
    • -
  • Tuesday, 2/23/2016 - Gan Sh/Sat Tr - Time: 23:30
    • Ganymede's shadow will transit Jupiter from 2355 to 0315, with Ganymede transiting from 2116 to 0425.
  • Wednesday, 2/24/2016 - Eur EcD - Time: 04:30
    • At 0445 Europa will disappear into Jupiter's shadow 0.2 Jupiter disk width west of Jupiter's limb.
  • Thursday, 2/25/2016 - Zod Light in W thru 3/9 - Time: 19:30
    • Look for the zodiacal light in the west after twilight from a dark site without western light pollution. Best times to look are from about 1940 to 2030.
  • Thursday, 2/25/2016 - Dbl Sh/Sat Tr of Jup - Time: 23:00
    • Sequence of events:
      2314 Europa's shadow transit begins
      2348 Europa begins to transit
      0137 Io's shadow transit begins
      - Start of double shadow transit
      0153 Io begins to transit
      - Start of double satellite transit
      0203 Europa's shadow transit ends
      - End of double shadow transit
      0233 Europa's transit ends
      - End of double satellite transit
      0353 Io's shadow transit ends
      0408 Io's transit ends
  • Friday, 2/26/2016 - Io EcD - Time: 22:30
    • At 2248 Io will disappear into Jupiter's shadow 0.1 Jupiter disk width west of Jupiter's limb. Io will reappear from behind the east limb at 0120.
  • Saturday, 2/27/2016 - Io Sh/Sat Tr - Time: 20:00
    • Io's shadow will transit Jupiter from 2005 to 2221, with Io transiting from 2019 to 2234. Also, at 2114 Europa will reappear from behind Jupiter's east limb.
  • Sunday, 2/28/2016 - Io OcR - Time: 19:30
    • At 1945 Io will reappear from behind Jupiter's east limb.
  • Monday, 2/29/2016 - Cal Sh/Sat Tr - Time: 19:00
    • Callisto's shadow will transit Jupiter from 1907 to 2216, with Callisto transiting from 2120 to 2318. These transits are interesting in that they cross Jupiter's north polar region. Note: Jupiter will only be 6° high in the east at 1907.

March 2016
  • Tuesday, 3/1/2016 - Last Qtr - Time: 15:00
    • -
  • Tuesday, 3/1/2016 - Zod Light in W thru 3/9 - Time: 19:30
    • Look for the zodiacal light in the west after twilight from a dark site without western light pollution. Best times to look are from about 1940 to 2030.
  • Friday, 3/4/2016 - Dbl Sh/Sat Tr of Jup - Time: 01:30
    • Sequence of events:
      0151 Europa's shadow transit begins
      0204 Europa begins to transit
      0331 Io's shadow transit begins
      - Start of double shadow transit
      0337 Io begins to transit
      - Start of double satellite transit
      0439 Europa's shadow transit ends
      - End of double shadow transit
      0449 Europa's transit ends
      - End of double satellite transit
      0546 Io's shadow transit ends
      0551 Io's transit ends
  • Friday, 3/4/2016 - Algol min - Time: 04:00
    • Algol eclipse minimum is at 0354.
  • Saturday, 3/5/2016 - Io Sh/Sat Tr - Time: 21:30
    • Note: Ganymede will reappear from behind Jupiter's east limb at 2126.
      Io's shadow will transit Jupiter from 2159 to 0015, with Io transiting from 2202 to 0017. Io follows its shadow so closely that the disks may just touch or slightly overlap, a very unusual situation that only occurs very near opposition. Also, Europa will reappear from behind Jupiter's east limb at 2327.
  • Monday, 3/7/2016 - Algol min - Time: 00:30
    • Algol eclipse minimum is at 0043.
  • Monday, 3/7/2016 - 3.2% Cr Mn v nr Ven - Time: 06:00
    • An ultra-thin 3.2% crescent moon will be very near Venus, with both very low in the ESE before sunrise.
  • Tuesday, 3/8/2016 - Jup opp - Time: 03:00
    • Jupiter is at opposition in Leo. It reaches magnitude -2.5 and a disk size of 44".
  • Tuesday, 3/8/2016 - New Moon - Time: 20:00
    • -
  • Wednesday, 3/9/2016 - Lrg Tides thru 2/12 - Time: 00:00
    • New moon occurs about 29 hours before perigee causing large tides.
  • Wednesday, 3/9/2016 - 1.6% Cr Mn - Time: 18:30
    • An ultra-thin 1.6% crescent moon will be 6° high 5° south of due west 30 minutes after sunset (or at 1842 calculated for the RFO site). Start looking 20 minutes after sunset and use binoculars.
  • Wednesday, 3/9/2016 - Algol min - Time: 20:30
    • Algol eclipse minimum is at 2032.
  • Saturday, 3/12/2016 - Algol min - Time: 18:30
    • Algol eclipse minimum is at 1821.
  • Saturday, 3/12/2016 - Occ of ZC464 - Time: 20:00
    • At about 2012 the magnitude 6.1 star ZC464 will disappear behind the moon's dark limb 31° from the north cusp. Calculated using Occult4 for the RFO site. Details will differ as distance from RFO increases.
  • Saturday, 3/12/2016 - Io Sat/Sh Tr - Time: 23:30
    • Note: Earlier this evening Ganymede disappears behind Jupiter's west limb at 2130 and Europa does the same at 2257.
      Note: The event times shown are PST, ignoring the change to PDT at 0200.
      Io transits Jupiter from 2346 to 0201 with its shadow transiting from 2353 to 0208. Since Jupiter is just past opposition, Io's shadow follows Io quite closely. Also, Ganymede will reappear from eclipse 0.1 Jupiter width east of Jupiter at 0115, and Europa will do the same at 0156.
  • Sunday, 3/13/2016 - DST begins - Time: 02:00
    • -
  • Sunday, 3/13/2016 - Io OcD & EcR - Time: 21:30
    • At 2157 Io will disappear behind Jupiter's west limb. It will then reappear from Jupiter's shadow VERY close to Jupiter's east limb at 0022.
  • Monday, 3/14/2016 - Dbl Sh/Sat Tr of Jup - Time: 19:00
    • Jupiter is low in the east at sunset, with the transits of Io and Europa and Europa's shadow transit already in progress. You might not yet be able to spot Jupiter for the first event listed below, but it should become apparent soon after.
      Sequence of events:
      1922 Io's shadow transit begins
      - Start of double shadow transit
      2045 End of astro twilight
      2113 Europa's transit ends
      - End of double satellite transit
      2127 Io's transit ends
      2134 Europa's shadow transit ends
      - End of double shadow transit
      2137 Io's shadow transit ends
  • Tuesday, 3/15/2016 - 1st Qtr - Time: 10:00
    • -
  • Saturday, 3/19/2016 - Vernal Equinox - Time: 21:30
    • The equinox occurs at 9:30pm.
  • Sunday, 3/20/2016 - Io Sat/Sh Tr - Time: 02:30
    • Note: Earlier Ganymede will disappear behind Jupiter's west limb at 0147 and Europa does the same at 0210.
      Io will transit Jupiter's disk from 0230 to 0445, followed by its shadow from 0246 to 0502. In addition, Europa reappears from Jupiter's shadow 0.2 Jupiter disk width east of Jupiter's limb at 0529, and Ganymede does the same 0.3 disk width east at 0614.
  • Sunday, 3/20/2016 - Io OcD - Time: 23:30
    • At 2342 Io will disappear behind Jupiter's west limb.
  • Monday, 3/21/2016 - Io EcR - Time: 02:00
    • At 0217 Io will reappear from Jupiter's shadow 0.1 Jupiter disk width east of Jupiter's limb.
  • Monday, 3/21/2016 - Occ of 48 Leo - Time: 02:00
    • At about 0215 magnitude 5.1 48 Leonis will disappear behind the moon's dark limb 85° from the north cusp. 48 Leo is an extreme close double so may be non-instantaneous for those with suitable equipment. Calculated using Occult4 for the RFO site. Details will differ as distance from RFO increases.
  • Monday, 3/21/2016 - Dbl Sh/Sat Tr of Jup - Time: 20:30
    • Sequence of events:
      2043 Europa begins to transit
      2053 End of astro twilight
      2056 Io begins to transit
      - Start of double satellite transit
      2115 Io's shadow transit begins
      2123 Europa's shadow transit begins
      - Start of double shadow transit
      2311 Io's transit ends
      - End of double satellite transit
      2329 Europa's transit ends
      2331 Io's shadow transit ends
      - End of double shadow transit
      0011 Europa's shadow transit ends

  • Monday, 3/21/2016 - Mn v nr Jup - Time: 21:00
    • -
  • Tuesday, 3/22/2016 - Io EcR - Time: 20:30
    • At 2046 Io will reappear from Jupiter's shadow 0.1 Jupiter disk width east of Jupiter's limb.
  • Wednesday, 3/23/2016 - Pen Lun Ecl - Time: 04:00
    • A deep punumbral lunar eclipse should produce noticeable if somewhat subtle darkening of the southern portion of the lunar disk around the eclipse maximum at 0447. While the official eclipse time is 0240 to 0653, the visually noticeable portion will be between 0417 and 0517, at most.
  • Wednesday, 3/23/2016 - "Worm" Moon - Time: 05:00
    • -
  • Friday, 3/25/2016 - Sat stat - Time: 06:00
    • Saturn begins retrograde motion.
  • Friday, 3/25/2016 - Cal OcR & Ec - Time: 21:00
    • This is an especially interesting sequence of events.
      First, Callisto reappears from behind the east limb of Jupiter's south polar region at 2118. Then Callisto disappears into Jupiter's shadow at 2241, to reappear from the shadow about 0.7 Jupiter disk width east of Jupiter's south polar region at 0136.
  • Friday, 3/25/2016 - Zod Light in W thru 4/7 - Time: 21:00
    • Look for the zodiacal light in the west after twilight from a dark site without western light pollution. Best times to look are from about 2110 to 2140.
  • Monday, 3/28/2016 - Dbl Sh/Sat Tr of Jup - Time: 22:30
    • Sequence of events:
      2241 Io begins to transit
      2300 Europa begins to transit
      - Start of double satellite transit
      2310 Io's shadow transit begins
      0000 Europa's shadow transit begins
      - Start of double shadow transit
      0055 Io's transit ends
      - End of double satellite transit
      0125 Io's shadow transit ends
      - End of double shadow transit
      0147 Europa's transit ends
      0247 Europa's shadow transit ends
  • Tuesday, 3/29/2016 - Io EcR - Time: 22:30
    • Io reappears from Jupiter's shadow 0.2 Jupiter disk width east of Jupiter at 2241.
  • Wednesday, 3/30/2016 - Gan Sat/Sh Tr & Eur EcR - Time: 20:30
    • Ganymede is already transiting Jupiter at sunset, before Jupiter becomes visible. Ganymede's shadow transits from 2046 to 0003, with Ganymede ending transit at 2153. Also, Europa will reappear from Jupiter's shadow 0.3 Jupiter disk width east of Jupiter at 2120.
  • Thursday, 3/31/2016 - Last Qtr - Time: 08:30
    • -

April 2016
  • Sunday, 4/3/2016 - Cal Tr - Time: 02:30
    • Callisto transits Jupiter's north polar region from 0240 to 0515.
  • Monday, 4/4/2016 - Dbl Sat/Sh Tr of Jup - Time: 24:00
    • Sequence of events:
      0026 Io begins to transit
      0104 Io's shadow transit begins
      0118 Europa begins to transit
      - Start of double satellite transit
      0237 Europa's shadow transit begins
      - Start of double shadow transit
      0240 Io's transit ends
      - End of double satellite transit
      0319 Io's shadow transit ends
      - End of double shadow transit
      0405 Europa's transit ends
      0524 Europa's shalow transit ends
  • Tuesday, 4/5/2016 - Io OcD & EcR - Time: 21:30
    • Io disappears behind Jupiter at 2139 and reappears from Jupiter's shadow 0.3 Jupiter disk width east of Jupiter at 0035.
  • Wednesday, 4/6/2016 - Io Sat/Sh Tr - Time: 20:30
    • Io and its shadow are in transit as Jupiter becomes visible in twilight. Io's transit ends at 2107 and the shadow transit ends at 2147.
  • Wednesday, 4/6/2016 - Mer in W thru 4/29 - Time: 20:30
    • Mercury has its best evening apparition of 2016 reaching a maximum altitude of 10° 45 minutes after sunset (or at 2034 at RFO) on 4/17. Mercury is dim during the first few days, then brightens. Start looking about 35 minutes after sunset.
  • Wednesday, 4/6/2016 - Gan Sat/Sh Tr & Eur EcR - Time: 22:00
    • Ganymede and its shadow transit Jupiter's north polar region. Ganymede's transit if from 2201 to 0116 and its shadow transits from 0045 to 0401. At 2354 Europa will reappear from Jupiter's shadow 0.4 Jupiter disk width east of Jupiter.
  • Thursday, 4/7/2016 - New Moon - Time: 04:30
    • -
  • Friday, 4/8/2016 - Very Lrg Tides thru 4/11 - Time: 00:00
    • New moon occurs less than 7 hours before a very close perigee causing VERY large tides, with extreme tides around 4/9.
  • Friday, 4/8/2016 - 4.4% Cr Mn - Time: 20:30
    • A very thin 4.4% crescent moon will be 8° high 8° north of due west 60 minutes after sunset. Begin looking 40 minutes after sunset.
  • Sunday, 4/10/2016 - Occ of Aldebaran - Time: 14:00
    • The moon provides a daytime occultation of the very bright red-orange star Aldebaran this afternoon from about 1421 to 1536, disappearing behind the dark limb and reappearing from behind the bright limb at axis angle 281° (or 84° from the north cusp). Calculated using Occult4 for the RFO site. Details will differ as distance from RFO increases.
  • Monday, 4/11/2016 - Occ of 130 Tau - Time: 20:30
    • At about 2053 the magnitude 5.5 star 130 Tauri will disappear behind the moon's dark limb 77° from the south cusp. Calculated using Occult4 for the RFO site. Details will differ as distance from RFO increases.
  • Tuesday, 4/12/2016 - Io OcD & EcR - Time: 23:00
    • Io disappears behind Jupiter at 2325 and reappears from Jupiter's shadow at 0230 0.3 Jupiter disk width east of Jupiter.
  • Wednesday, 4/13/2016 - Io Sat/Sh Tr & Eur OcD/EcR & Gan Tr - Time: 20:30
    • Io transits Jupiter from 2038 to 2253 and its shadow transits from 2126 to 2341.
      Europa disappears behind Jupiter at 2206 and reappears from Jupiter's shadow 0.5 Jupiter disk width east of Jupiter at 0227, while Ganymede begins transiting Jupiter's north polar region at 0127.
  • Wednesday, 4/13/2016 - 1st Qtr - Time: 21:00
    • -
  • Thursday, 4/14/2016 - Io EcR - Time: 20:30
    • Io reappears from Jupiter's shadow 0.3 Jupiter disk width east of Jupiter at 2059.
  • Saturday, 4/16/2016 - Occ of xi Leo - Time: 00:30
    • At about 0049 magnitude 5.0 xi Leonis will disappear behind the moon's dark limb 79° from the north cusp. Calculated using Occult4 for the RFO site. Details will differ as distance from RFO increases.
  • Saturday, 4/16/2016 - Mar stat - Time: 19:00
    • Mars begins retrograde motion.
  • Sunday, 4/17/2016 - Gan EcR - Time: 22:00
    • Ganymede reappears from Jupiter's shadow 0.9 Jupiter disk width east of Jupiter at 2206.
  • Sunday, 4/17/2016 - Mn v nr Jup - Time: 22:00
    • -
  • Wednesday, 4/20/2016 - Io Sat/Sh Tr - Time: 22:00
    • Io transits Jupiter from 2226 to 0041 followed by its shadow from 2320 to 0135. At 0026 Europa disappears behind Jupiter.
  • Thursday, 4/21/2016 - "Pink" Moon - Time: 22:30
    • -
  • Thursday, 4/21/2016 - Io EcR - Time: 22:30
    • Io reappears from Jupiter's shadow 0.4 Jupiter disk width east of Jupiter at 2254.
  • Friday, 4/22/2016 - Eur Sat/Sh Tr - Time: 21:00
    • Europa is in transit as Jupiter becomes visible in twilight, ending at 2159. Europa's shadow transits from 2109 to 2355.
  • Sunday, 4/24/2016 - Mn nr Mar, Antares & Sat - Time: 00:30
    • Rising in the east, Mars is slightly above and north of the similarly colored star Antares, with Saturn slightly below and north of Mars. The moon is above this trio.
  • Sunday, 4/24/2016 - Gan OcD & Ec - Time: 22:00
    • This is a nice opportunity to watch Ganymede emerge from behind Jupiter, at 2207, then disappear into Jupiter's shadow at 2250 and reappear 1.0 Jupiter disk east of Jupiter at 0206.
  • Monday, 4/25/2016 - Mn nr Mar, Antares & Sat - Time: 00:30
    • Rising in the east, the moon is very near Mars, which is slightly above and north of the similarly colored star Antares, with Saturn slightly below and north of Mars.
  • Tuesday, 4/26/2016 - Mn nr Mar, Antares & Sat - Time: 00:30
    • Rising in the east, the moon is very near Saturn, with Mars slightly above and south of Saturn and the orange-red star Antares slightly below and south of Mars.
  • Tuesday, 4/26/2016 - Juno Opp - Time: 20:00
    • The minor planet Juno is at opposition in Virgo at magnitude 10. About 3° southwest of 109 Virginis, consult references for observing it.
  • Wednesday, 4/27/2016 - Io Sat/Sh Tr - Time: 24:00
    • Io transits from 0014 to 0229, followed by its shadow from 0115 to 0330 (at which time Jupiter is 8° high in the west). During this time, Callisto disappears behind Jupiter's south polar region at 0045 and Europa disappears behind Jupiter at 0249.
  • Thursday, 4/28/2016 - Io OcD & EcR - Time: 21:00
    • Io disappears behind Jupiter at 2129 and reappears from Jupiter's shadow 0.4 Jupiter disk width east of Jupiter at 0049.
  • Friday, 4/29/2016 - Last Qtr - Time: 20:30
    • -
  • Friday, 4/29/2016 - Io Sh Tr & Eur Sat/Sh Tr - Time: 21:30
    • Io's shadow is in transit as Jupiter becomes visible in twilight, ending at 2158. Europa transits from 2137 to 0035, followed by its shadow from 2346 to 0232.

May 2016
  • Sunday, 5/1/2016 - Gan Oc & EcD - Time: 22:00
    • Ganymede disappears behind Jupiter at 2224 (start watching by 2200). It reappears from behind Jupiter at 0145 and then disappears into Jupiter's shadow at 0250.
  • Thursday, 5/5/2016 - Eta Aquarids peak - Time: 13:00
    • While the peak is during the day locally, meteor activity is high for a long period around the peak. So best observing of these meteors should be the moonless morning of 5/5 from 2am, when the radiant rises, until twilight begins around 4:30 am or so. Often bright and with long trails, about 30 meteors per hour are expected.
  • Friday, 5/6/2016 - Lrg Tides thru 5/9 - Time: 00:00
    • New moon occurs about 15 hours after perigee producing large tides. This is the last of a 3-month sequence with large tides around the new moon.
  • Friday, 5/6/2016 - New Moon - Time: 12:30
    • -
  • Friday, 5/6/2016 - Dbl Sh Tr & Eur Sat/Sh Tr - Time: 21:30
    • Io is already in transit, as is Ganymede's shadow in the north polar region, when Jupiter becomes visible during twilight. The sequence of events:
      2138 Io's shadow transit begins
      - Start of double shadow transit
      2242 Ganymede's shadow transit ends
      - End of double shadow transit
      2247 Io's transit ends
      2353 Io's shadow transit ends
      0005 Europa's transit begins
      0224 Europa's shadow transit begins
      0253 Europa's transit ends
      (Jupiter's altitude is 8° in the west by this time.)
  • Saturday, 5/7/2016 - Io EcR - Time: 21:00
    • At 2113, Io reappears from Jupiter's shadow 0.5 Jupiter disk width east of Jupiter.
  • Sunday, 5/8/2016 - Occ of 111 Tau - Time: 21:30
    • At about 2135 the magnitude 5.0 star 111 Tauri will disappear behind the moon's dark limb 63° from the south cusp. The moon will by 8° high in the west-northwest. 11 Tau is a triple star with 8th magnitude companions (requiring larger aperture for possible occultation viewing of the companions). Calculated using Occult4 for the RFO site. Details will differ as distance from RFO increases.
  • Monday, 5/9/2016 - Mer Tr of the Sun - Time: 06:30
    • This is a very special event that occurs only 13 or 14 times per century. The next Mercury transit (also viewable locally) is in November of 2019. The next one after that viewable locally won't occur until May of 2049.
      0604 the sun rises with Mercury already in transit
      0702 the sun is at an altitude of 10° (at RFO)
      0758 maximum transit (Mercury nearest the sun's center)
      1139 internal egress (leading edge of Mercury meets the sun's limb)
      1142 external egress (the trailing edge of Mercury leaves the sun's disk)
      IMPORTANT: Only scopes properly equipped for solar observing with solar filters should attempt observing this event.
  • Monday, 5/9/2016 - Jup stat - Time: 16:00
    • Jupiter ends retrograde motion.
  • Thursday, 5/12/2016 - Gan Sh Tr - Time: 21:30
    • Ganymede's shadow is already in transit when Jupiter becomes visible in twilight. The shadow transit ends at 2350.
  • Friday, 5/13/2016 - 1st Qtr - Time: 10:00
    • -
  • Friday, 5/13/2016 - Io Sat/Sh Tr - Time: 22:00
    • Io transits Jupiter from 2222 to 0038 followed by its shadow from 2333 to 0147.
  • Saturday, 5/14/2016 - Io EcR - Time: 23:00
    • At 2308 Io reappears from Jupiter's shadow 0.5 Jupiter disk width east of Jupiter, which is just north of where Callisto will be!
  • Sunday, 5/15/2016 - Mn v nr Jup - Time: 01:00
    • -
  • Tuesday, 5/17/2016 - Occ of theta Vir - Time: 23:00
    • At about 2321 magnitude 4.4 theta Virginis will disappear behind the moon's dark limb 79° from the south cusp. Theta Vir is an extremely close double and a multiple star. Calculated using Occult4 for the RFO site. Details will differ as distance from RFO increases.
  • Friday, 5/20/2016 - Gan Sh Tr - Time: 00:30
    • Ganymede's shadow begins transiting Jupiter's north temperate zone at 0039 and is still in progress when Jupiter sets at 0245.
  • Friday, 5/20/2016 - Io Sat/Sh Tr - Time: 24:00
    • Note that this event occurs on the morning of 5/21. Io transits Jupiter from 0015 to 0230 (which is shortly before Jupiter sets). Io's shadow transits starting at 0128 and is still in progress when Jupiter sets.
  • Saturday, 5/21/2016 - "Flower" Moon - Time: 14:00
    • This is the smallest full moon of 2016.
  • Sunday, 5/22/2016 - Io EcR - Time: 01:00
    • At 0103, Io reappears from Jupiter's shadow 0.5 Jupiter disk width east of Jupiter.
  • Sunday, 5/22/2016 - Mar opp - Time: 04:00
    • (See "Mars closest" event on 5/30.)
  • Sunday, 5/22/2016 - Io Sh Tr - Time: 21:00
    • Already in progress when Jupiter becomes visible in twilight, Io's shadow transit ends at 2210.
  • Tuesday, 5/24/2016 - Eur Sat/Sh Tr - Time: 20:30
    • Europa is in transit as Jupiter becomes visible in twilight, ending transit at 2111. Europa's shadow transits from 2057 to 2340.
  • Thursday, 5/26/2016 - Gan Tr - Time: 23:30
    • Ganymede begins transit of Jupiter at 2331.
  • Sunday, 5/29/2016 - Last Qtr - Time: 05:00
    • -
  • Sunday, 5/29/2016 - Io Sat/Sh Tr - Time: 21:30
    • Io is in transit as Jupiter becomes visible in twilight, ending its transit at 2251. Io's shadow transits from 2151 to 0005.
  • Monday, 5/30/2016 - Mar closest - Time: 15:00
    • 8 days after opposition, Mars, in Scorpius, is now closest to earth. Mars reaches magnitude -2.1 and a disk size of 19". The receding north ice cap of Mars is tilted 12° toward earth at position angle 37° (37° east of Celestial North).
  • Monday, 5/30/2016 - Gan EcR - Time: 21:30
    • Ganymede reappears from Jupiter's shadow 1.3 Jupiter disk widths east of Jupiter.
  • Monday, 5/30/2016 - Io EcR - Time: 21:00
    • This event occurs in mid-twilight. At 2127 Io reappears from Jupiter's shadow 0.5 Jupiter disk width east of Jupiter.
  • Tuesday, 5/31/2016 - Eur Sat/Sh Tr & Cal Ec - Time: 23:00
    • Europa is already in transit at twilight. Then...
      2306 Callisto disappears into Jupiter's shadow 1.8 Jupiter disk widths east of Jupiter
      2334 Europa's shadow begins to transit (continuing until Jupiter sets)
      2346 Europa's transit ends
      0111 Callisto reappears from Jupiter's shadow 2.2 Jupiter disk widths east of Jupiter, which is now 9° high in the west.

June 2016
  • Thursday, 6/2/2016 - Sat opp - Time: 23:00
    • -
  • Saturday, 6/4/2016 - New Moon - Time: 20:00
    • -
  • Sunday, 6/12/2016 - 1st Qtr - Time: 01:00
    • -
  • Tuesday, 6/14/2016 - Nep stat - Time: 01:00
    • Neptune begins retrograde motion.
  • Monday, 6/20/2016 - "Strawberry" Moon - Time: 04:00
    • -
  • Monday, 6/20/2016 - Solstice - Time: 15:30
    • The summer solstice occurs at 3:34pm.
  • Monday, 6/27/2016 - Last Qtr - Time: 11:30
    • -
  • Thursday, 6/30/2016 - Mar stat - Time: 01:00
    • Mars ends retrograde motion.

July 2016
  • Monday, 7/4/2016 - New Moon - Time: 04:00
    • -
  • Thursday, 7/7/2016 - Plu opp - Time: 15:00
    • -
  • Monday, 7/11/2016 - 1st Qtr - Time: 18:00
    • -
  • Tuesday, 7/19/2016 - "Buck" Moon - Time: 16:00
    • -
  • Tuesday, 7/26/2016 - Last Qtr - Time: 16:00
    • -
  • Friday, 7/29/2016 - Ura stat - Time: 18:00
    • Uranus begins retrograde motion.

August 2016
  • Tuesday, 8/2/2016 - New Moon - Time: 13:30
    • -
  • Wednesday, 8/10/2016 - 1st Qtr - Time: 11:30
    • -
  • Friday, 8/12/2016 - Perseids peak - Time: 07:00
    • Peak rates of about 150 meteors per hour are expected this year, though the timing of the peak is uncertain, as always. A waxing gibbous moon interferes until after setting around 1:20am on 8/12. Meteor viewing should then be good until twilight begins around 4:45am or so. Meteor watchers should try the morning hours of the days preceding 8/12 since the moon will set earlier and be less of a problem.
  • Saturday, 8/13/2016 - Sat stat - Time: 10:00
    • Saturn ends retrograde motion.
  • Thursday, 8/18/2016 - "Sturgeon" Moon - Time: 02:30
    • -
  • Wednesday, 8/24/2016 - Last Qtr - Time: 21:00
    • -

September 2016
  • Thursday, 9/1/2016 - New Moon - Time: 02:00
    • -
  • Friday, 9/2/2016 - Nep opp - Time: 09:00
    • -
  • Saturday, 9/10/2016 - 1st Qtr - Time: 05:00
    • -
  • Friday, 9/16/2016 - "Harvest" Moon - Time: 12:00
    • -
  • Thursday, 9/22/2016 - Autumnal Equinox - Time: 07:30
    • The equinox is at 7:21am.
  • Friday, 9/23/2016 - Last Qtr - Time: 03:00
    • -
  • Friday, 9/30/2016 - New Moon - Time: 17:00
    • -

October 2016
  • Saturday, 10/8/2016 - 1st Qtr - Time: 21:30
    • -
  • Saturday, 10/15/2016 - Ura Opp - Time: 03:00
    • -
  • Saturday, 10/15/2016 - "Hunter's" Moon - Time: 21:30
  • Saturday, 10/22/2016 - Last Qtr - Time: 12:00
    • -
  • Sunday, 10/30/2016 - New Moon - Time: 10:30
    • -

November 2016
  • Sunday, 11/6/2016 - DST Ends - Time: 02:00
    • -
  • Monday, 11/7/2016 - 1st Qtr - Time: 12:00
    • -
  • Monday, 11/14/2016 - "Beaver" Moon - Time: 06:00
  • Sunday, 11/20/2016 - Nep stat - Time: 02:00
    • Neptune ends retrograde motion.
  • Monday, 11/21/2016 - Last Qtr - Time: 00:30
    • -
  • Tuesday, 11/29/2016 - New Moon - Time: 04:30
    • -

December 2016
  • Wednesday, 12/7/2016 - 1st Qtr - Time: 01:00
    • -
  • Tuesday, 12/13/2016 - "Cold" Moon - Time: 16:00
    • -
  • Wednesday, 12/21/2016 - Winter Solstice - Time: 02:30
    • The winter solstice is at 2:44am.
  • Wednesday, 12/21/2016 - Last Qtr - Time: 18:00
    • -
  • Wednesday, 12/28/2016 - New Moon - Time: 23:00
    • -
  • Thursday, 12/29/2016 - Ura stat - Time: 08:00
    • Uranus ends retrograde motion.

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