This week is the maximum of one of the more active autumn meteor showers - the Orionids, Pencho Markishki, a physicist at the Institute of Astronomy with the National Academy of Sciences of the Bulgarian Academy of Sciences and at the Department of Astronomy of the Faculty of Physics of Sofia University "St. Kliment Ohridski" (SU), told BTA.
The Orionids are generated by meteor swarms that separated into space from Halley's Comet (1P/Halley), the specialist explained. The Earth crosses these swarms twice a year - from April 19 to May 28, when the Eta-Aquarids stream is active, and from October 2 to November 7, when the Orionids are active.
This year, the maximum of the Orionids will occur on October 21 at around 9:30 p.m. Bulgarian time, Markishki specified. According to him, on the night of October 21 to 22, the Moon will set at 3:23 a.m. for Sofia with an 81% illuminated disk and until then it will make observations difficult. The activity of the stream during the maximum is about 20 fast white meteors per hour. These meteors can be observed after the sunrise of the Orionids radiant in the constellation Orion – from around 11 p.m. for the Sofia area, the physicist specified. "However, given the bright Moon, it will be more appropriate to conduct observations from the moment of moonset until the onset of morning twilight around 06:30. It is recommended that observations be made from dark places, sufficiently distant from the night lights of cities and industrial areas," said Markishki, who is the author of the reference book "Amateur Astronomer's Guide" of the Department of Astronomy at Sofia University, already published as a book, and advises amateur astronomers when conducting observations.
The maximum of the Draconids meteor shower was in early October. Usually, this stream has low activity, reaching about 5-10 meteors per hour during the maximum. The meteors are slow, yellow-orange in color.
The maximum of the Perseid shower was in mid-August, BTA recalls.