CentaurZ

During the predawn hours of 2021 APR 02, there may appear to be a fifth Galilean satellite around Jupiter. Actually, it will be the magnitude +5.9 star 44 Capricorni. Some observers in eastern North America may be able to witness the star during nighttime being occulted by Jupiter for over an hour. This would be a daytime occultation for Europe. Optical aid would be needed to witness this due to the brilliance of Jupiter overwhelming the star. I calculate that the star will be occulted from 08:48 to 10:00 UT (03:48 to 05:00 CDT – 04:48 to 06:00 EDT). Photos and descriptions of the event would be welcome additions to this thread.

During the predawn hours of 2021 APR 02, there may appear to be a fifth Galilean satellite around Jupiter. Actually, it will be the magnitude +5.9 star 44 Capricorni. Some observers in eastern North America may be able to witness the star being occulted by Jupiter during nighttime for over an hour. This would be a daytime occultation in Europe. Optical aid would be needed to witness this due to the brilliance of Jupiter overwhelming the star. I calculate that the star will be occulted from 08:48 to 10:00 UT (03:48 to 05:00 CDT – 04:48 to 06:00 EDT). Photos and descriptions of the event would be welcome additions to my similar thread in the forum for Observing-Planetary.

Asteroid 15 Eunomia is currently the second brightest asteroid at magnitude +8.6. Eunomia will appear within Cancer in opposition to the Sun on 2021 JAN 21 at magnitude +8.4. Eunomia is the most massive stony asteroid. It was discovered in 1851, and has a mean diameter of 268 km. Photos and descriptions of Eunomia would be welcome additions to this thread.

Mercury, Jupiter & Saturn will form a tight trio in the early evening southwestern sky during the weekend of 2021 JAN 09-10. Photos and descriptions of the grouping would be welcome additions to my similar thread in the forum for Observing-Planetary.

Mercury, Jupiter & Saturn will form a tight trio in the early evening southwestern sky during the weekend of 2021 JAN 09-10. Photos and descriptions of the grouping would be welcome additions to this thread.

Elusive Mercury has commenced its apparition in the western sky after sunset following its superior conjunction behind the Sun on 2020 DEC 19. This should be a rather favorable apparition except for observers south of the tropics. Photos and descriptions of Mercury during this apparition would be welcome additions to this thread.

During periods of about six months separated by about six years, mutual events occur involving the Galilean satellites occulting and transiting each other, with similar effects from their shadows. The next such period will commence on 2021 JAN 03 and end on 2021 JUN 26. Photos and descriptions of these events would be welcome additions to my similar thread in the forum for Observing-Planetary. The timing predictions posted below should not vary by much more than one second among locations.

During periods of about six months separated by about six years, mutual events occur involving the Galilean satellites occulting and transiting each other, with similar effects from their shadows. The next such period will commence on 2021 JAN 03 and end on 2021 JUN 26. Photos and descriptions of these events would be welcome additions to this thread. The timing predictions posted below should not vary by much more than one second among locations.

The annual Quadrantid Meteor Shower may already be underway, and is expected to peak during the night of 2021 JAN 02-03. Its radiant is in the no longer official constellation Quadrans Muralis, which is now part of Boötes. That is the direction toward which the meteor tails point, but the meteors are equally likely to appear anywhere in your sky. It is conjectured that the Quadrantids are debris from the asteroid 2003 EH1, which in turn may have been a castoff from comet C/1490 Y1. The peak rate of the Quadrantids can be as great as the normally most prolific annual showers at possibly a hundred per hour for sharp eyed observers in dark skies. However, the peak period of less than half a day is unusually short, thus implying a narrow stream of particles. Also, the meteors are normally not very bright. The show begins after Boötes rises, which is around local midnight for mid-latitude northern hemisphere observers, but later in the southern hemisphere. It will continue through morning twilight. Some interference might be expected during the peak from the waning gibbous Moon. Descriptions of the shower or perhaps even lucky photos would be welcome additions to this thread.

I noted in my original post that occultations of Saturn by Jupiter are exceptionally rare. And we also don't see mutual planetary occultations very often in the cases of any pairs of planets. We are currently in an unusually long dry spell. The most recent case was an 1818 occultation of Jupiter by Venus, with no observation reports. The only report ever of a mutual planetary occultation was by an amateur astronomer who observed Venus occulting Mercury in 1737. The next mutual planetary occultation will be when Venus occults Jupiter in 2065, but that will be almost impossible to observe with an elongation from the Sun of only 8˚. 🙁

Indeed, there have been less complete descriptions published elsewhere. 2080 might also be difficult for me, since I am currently 75. 😉 I noted in my original post that occultations of Saturn by Jupiter are exceptionally rare. And we also don't see mutual planetary occultations very often in the cases of any pairs of planets. We are currently in an unusually long dry spell. The most recent case was an 1818 occultation of Jupiter by Venus, with no observation reports. The only report ever of a mutual planetary occultation was by an amateur astronomer who observed Venus occulting Mercury in 1737. The next mutual planetary occultation will be when Venus occults Jupiter in 2065, but that will be almost impossible to observe with an elongation from the Sun of only 8˚. 🙁

The hour has arrived. 😎

Only one more day to go. 😎

The annual Geminid Meteor Shower may already be underway. It is expected to peak during the night of 2020 DEC 13-14. Its radiant is in the constellation Gemini. That is the direction toward which the meteor tails point, but the meteors are equally likely to appear anywhere in your sky. The Geminids are debris from the asteroid 3200 Phaethon. The Geminids have been presenting an increasingly intense shower in recent years. At the peak between 120 and 160 meteors per hour may be seen by some sharp-eyed folks. The show begins after Gemini rises in the early evening and intensifies until morning twilight. Although observers south of the tropics will have to wait until midnight. The waning crescent Moon during the shower’s peak this year should not provide interference. Descriptions of the shower or perhaps even lucky photos would be welcome additions to this thread.

I noted in my opening post that this will be the narrowest angular separation between the two since 1623. Actually, the pair in 1623 was separated by only 5.2 arcminutes, but at an elongation from the Sun of less than 13˚. That would have been quite difficult to observe by naked eyes. The next earlier yet better separation than in 2020 was in 1226 at 2.1 arcminutes separation and 49˚ from the Sun. The 2080 separation will be 6.0 arcminutes, barely less than this year's 6.1 arcminutes. But the 44˚ elongation from the Sun will be better than this year's 30˚.

A Penumbral Lunar Eclipse will be presented to many observers with clear skies in the Americas, Northern Europe, East Asia, Australia and New Zealand during the night of 2020 NOV 29-30. All of the event may be visible from North America, but only a portion of it in the other mentioned locations. The Earth’s penumbra is its relatively bright fringe shadow surrounding its much darker inner shadow called the umbra. At maximum eclipse, 82% of the Moon’s diameter will be covered by the penumbra. The Moon’s nearest portion of its limb to the umbra will miss it by 27% of the Moon’s diameter. Often a penumbral lunar eclipse is hardly noticeable, but this time a darkening near a portion of the limb should be apparent. 2020 has been an unusual year in which there are four lunar eclipses, and all of them penumbral. The next umbral eclipse will be total and occur on 2021 MAY 26. Below is my preview graphic for the upcoming penumbral eclipse as seen against an imaginary blue wall to make the shadow fully apparent. The predicted event timings are in CST (UT-6), but will occur at essentially the same real time for all observers experiencing nighttime. The depicted orientation and Moon altitudes are for an observer in Chicago. Photos and descriptions of the eclipse would be welcome additions to my similar thread in the forum for Observing-Lunar.

A Penumbral Lunar Eclipse will be presented to many observers with clear skies in the Americas, Northern Europe, East Asia, Australia and New Zealand during the night of 2020 NOV 29-30. All of the event may be visible from North America, but only a portion of it in the other mentioned locations. The Earth’s penumbra is its relatively bright fringe shadow surrounding its much darker inner shadow called the umbra. At maximum eclipse, 82% of the Moon’s diameter will be covered by the penumbra. The Moon’s nearest portion of its limb to the umbra will miss it by 27% of the Moon’s diameter. Often a penumbral lunar eclipse is hardly noticeable, but this time a darkening near a portion of the limb should be apparent. 2020 has been an unusual year in which there are four lunar eclipses, and all of them penumbral. The next umbral eclipse will be total and occur on 2021 MAY 26. Below is my preview graphic for the upcoming penumbral eclipse as seen against an imaginary blue wall to make the shadow fully apparent. The predicted event timings are in CST (UT-6), but will occur at essentially the same real time for all observers experiencing nighttime. The depicted orientation and Moon altitudes are for an observer in Chicago. Photos and descriptions of the eclipse would be welcome additions to this thread.

The annual Leonid Meteor Shower should already be underway. It is expected to peak during the night of 2020 NOV 16-17. Its radiant is in the constellation Leo. That is the direction toward which the meteor tails point, but the meteors are equally likely to appear anywhere in your sky. The Leonids are debris from the periodic comet 55P Tempel-Tuttle. The Leonids vary considerably each year in their rates. At the peak, sharp-eyed observers may see as few as ten meteors per hour or as many as a hundred, although in exceptional years this can reach the thousands. This year the expectation is for around 10 to 15 per hour. The real show begins after Leo rises around midnight and intensifies until morning twilight. At the shower’s peak the waxing crescent Moon should not provide interference. Descriptions of the shower or perhaps even lucky photos would be welcome additions to this thread.

It’s nearly time for my monthly New Moon spotting challenge. I use the term New Moon in its classical sense of one’s first sighting of the Moon after its monthly solar conjunction (Dark Moon). Sharp-eyed observers may attempt to spot the less than one-day-old Moon after sunset on Sunday, November 15th. Photos and descriptions of the young crescent Moon this month would be welcome additions to this thread.

On 2020 DEC 21 at 18:21 UT Jupiter and Saturn will appear to have a geocentric angular separation of only 6.1 arcminutes, the narrowest since 1623 and until 2080. However, those separations are not small enough for Jupiter to occult Saturn. The last such occultation occurred in 6857 BC, while the next two will both occur during 7541. Great conjunctions between Jupiter and Saturn occur about every 20 years. That’s their mutual synodic (lapping) period with a mean value of 19.86 years. Sometimes the conjunctions are triple due to the effect of apparent retrograde motion, but not this time. Photos and descriptions of the upcoming conjunction would be welcome additions to my similar thread in the Observing-Planetary forum.

On 2020 DEC 21 at 18:21 UT Jupiter and Saturn will appear to have a geocentric angular separation of only 6.1 arcminutes, the narrowest since 1623 and until 2080. However, those separations are not small enough for Jupiter to occult Saturn. The last such occultation occurred in 6857 BC, while the next two will both occur during 7541. Great conjunctions between Jupiter and Saturn occur about every 20 years. That’s their mutual synodic (lapping) period with a mean value of 19.86 years. Sometimes the conjunctions are triple due to the effect of apparent retrograde motion, but not this time. Photos and descriptions of the upcoming conjunction would be welcome additions to this thread.

Elusive Mercury has commenced its apparition in the predawn eastern sky following its inferior conjunction between Earth and Sun on 2020 OCT 25. This a favorable apparition for observers other than those south of the tropics. Photos and descriptions of Mercury during this apparition would be welcome additions to this thread.

Uranus will appear in opposition to the Sun during 2020 OCT 31. At magnitude +5.7 it may be visible to sharp naked eyes under dark skies, although the Full Moon at the time of opposition would be a hindrance. It has always amazed me that Uranus was not discovered until William Herschel pointed a telescope at it in 1781. I would imagine that countless people observed it by naked eye before then, but assumed it was a fixed star and never noticed that over a period of time it changed position relative to the actual fixed stars. I first observed it by naked eye nearly fifty years ago, but of course I knew that it existed and exactly where to look. Photos and descriptions of Uranus would be welcome additions to this thread.

The Lunar X may be seen by telescopic observers in the Americas during the evening of Friday 2020 OCT 23 for an approximately four-hour period centered on 22:20 CDT (OCT 24 at 03:20 UT). The X should appear as the Sun rises on the clustered rims of the craters Blanchinus, La Caille and Purbach, while a waxing Half Moon graces the sky. This is something to check-off from your astronomical “to-do” list. Photos and descriptions of the Lunar X would be welcome additions to this thread.

Asteroid 8 Flora is currently the second brightest asteroid at magnitude +8.2, barely dimmer than 4 Vesta at +8.1. Flora will appear within Cetus in opposition to the Sun on 2020 NOV 01 at magnitude +8.0. Flora was discovered in 1847. It has a mean diameter of 128 km. It is the innermost large asteroid. Photos and descriptions of Flora would be welcome additions to this thread.