Archive for year: 2024

Image: Looking towards the centre of our Milky Way Galaxy.  Credit: Mark Justice

August

At this time of the Year the spectacular heart of our Milky Way Galaxy is now setting earlier and the best views for this year end this month.

• 9th Moon at Apogee, furthest from Earth for the month 11:34hrs AEST, 405,295.5km.
• 11th  Saturn is rising at 20.08hrs AEST and is at a distance 1,312,914,389 km, magnitude +0.8 and is moving closer and due to reach opposition on 8th September. tilt of planet is 2.7469 degrees, almost edge on.
• 11th Jupiter is rising at 03:13hrs AEST with magnitude -2.2, distance 811,025,822 km. Locate low in the East near Mars rising at 03:04hrs AEST at magnitude 0.9.

Meteor Showers

• 12th-13th Perseid Meteor shower peaks very low in the East. This is not a good shower for the Southern Hemisphere but some meteors could be visible just before dawn, start observing from after midnight on 12th August. Jupiter and Mars are up also at this time.

The shower is active: July 17–August 24; Maximum: August 12, 13h to 16h UT   August 12th 23h – August 13th 04hrs Ballarat Time. The Meteor rate ZHR = 100 for Northern Hemisphere viewers.

The orbital period of the parent comet 109P/Swift-Tuttle is about 130 years. The Perseids produced strong activity from a primary maximum throughout the 1990s. Enhanced activity was last observed in 2016 due to passages through separated dust trails.
A filament crossing occurred on 2018 August 12 around 20h UT  06h Ballarat time. (A filament is thought to be an accumulation
of meteoroids in a mean-motion resonance.)
High activity well after the main peak has been reported during some recent returns. On 2021 August 14, shortly after 08hUT , a sharp increase of the ZHR – more than 100 above the basic level – was observed by different techniques. This was about 1.5 days after the
nodal maximum and about 0.7 days after the lesser late maxima in 2018 and 2020. Nothing similar has been observed during the 2022 return.
J´eremie Vaubaillon noted that there are encounters with five very old trails (four of them more than 1,300 years old) mainly on August 12 between 04h and 11h UT. Monitoring activity during this period is of interest because such observations are scarce.

DATA Credit: IMO

May

• 6th  Peak 07:00hrs AEST  eta Aquariids (ETA) Active from April 19th to May 28th, 2024  but high numbers can be seen either side of this date. The Eta Aquariids are a strong shower when viewed from the southern tropics. From the equator northward, they usually only produce medium rates of 10-30 per hour just before dawn. Activity is good for a week centered the night of maximum activity. These are swift meteors that produce a high percentage of persistent trains, but few fireballs. Parent body is Comet 1P/Halley
  Shower details – Radiant: 22:32 -1° – ZHR: 50 can very from 40-85)  in a darksky – Velocity: 42 miles/sec (swift – 66.9km/sec) – Parent Object: 1P/HalleyOn this night, the moon is a waning crescent 28.03 days old and will be 6% full.The meteors are only visible in the hours before dawn essentially from our southern hemisphere sites and is one of the best showers for southern observers.
  This year there is no moonlight interference around the maximum period (New Moon on May 8). 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. However, there might be enhanced activity (Egal, 2020) related to the 1:6 mean motion resonance in 2023 and 2024 – hence observers should try to monitor the
  activity of the near-peak period which extends from May 4 to 6.
• Recent peak ZHRs were:
  2008 2009 2017 2018 2019 2020 2021 2022 2023
  ≈ 85  ≈ 70       75      60    50     50      45      42     40 (preliminary)
  Mikhail Maslov’s calculations reveal that in 2024 the Earth comes close to meteoroids ejected from the comet in −985. Meteoroids of the trail had ejection velocities of ≥ 10 m/s. Observers
  might see some activity increase on May 3 between 05h and 08h UT. The ejection velocity range suggests that the trail is composed of comparatively large particles so that there might be a
  larger portion of bright meteors.
• 6th Moon at Perigee closest to Earth for the month, 08:05hrs AEST, 363,164.5km.
• 11th The Sun is at the peak of Solar Cycle 25, putting on light shows which are the best to be seen anywhere on Earth, producing Red Night!! There is possibly more on the way, we have to wait and see.

• 

  Red Night – Credit: Judith Bailey iPhone 11 ISO 8000 26mm 1.1 sec,  21hrs AEST 11th May 2024 Clarendon Vic AU

• 15th Sunspot 3685 is coming from around the edge of the East limb and is looking very promising with an X3 class flare, this video taken from SDO on 15th May. Also the video shows that activity from Sunspot 3664 is still very active, it has disappeared behind the West limb and whatever form it takes over time, will be back at the East limb in about ~ 11 days. Note the flashes, this is solar lightning on a very scary scale, it is fantastic to see aurora on the recent scale we have seen, but to have it scaled down a bit, is best for all life on Earth The Goldilocks zone is best when not to hot and not too cold, also we could add, not too intense X class flare!

• 18th Moon at Apogee furthest from Earth for the month 04:58hrs AEST, 404,639.0 km.