What’s in the Sky in May

 

May

• Eta Aquarid Meteor Shower Active: April 19–May 28; Maximum: May 6, 03h UT ; ZHR = 50 (var., 40–85)  under a dark sky;  V∞ = 66 km/s.  A clear view to the low NE sky is necessary to view this meteor shower.

This stream is associated with Comet 1P/Halley, like the Orionids of October. Shower meteors are only visible in the hours before dawn essentially from tropical and southern hemisphere sites. The shower is one of the best for southern observers. Useful results may be obtained from places up to about 40◦ N latitude. The radiant culminates near 8h local time. In most years, a substantial amount of optical ETA-data is collected worldwide. However, due to the relatively short observing window between radiant rise and morning twilight for each site, it remains difficult to obtain a continuous profile.
This year the moonlight interference increases after the maximum period (Full Moon on May 12). IMO analyses of visual data collected since 1984 have shown that ZHRs are generally above 30 in the period May 3–10. An often claimed variability of the peak rates associated with Jupiter’s orbital period close to 12 years has not been confirmed in a recent study (Egal et al., 2020) using optical and radar data.
The preliminary data of the 2024 return shows slightly enhanced rates at a rather late position on May 8.
Recent peak ZHRs were:
2008  2009 2017 2018 2019 2020 2021 2022 2023 2024
≈ 85  ≈ 70      75      60     50      50     45      42      40      45 (preliminary)

Credit: IMO

• 11th Moon at Apogee furthest from Earth for the month 11:47hrs AEST, 404,241.6 km.
• 26th Moon at Perigee closest to Earth for the month, 12:32hrs AEST, 359,023.0km.