What’s in the Sky in August

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