A total lunar eclipse recently observed in Russia`s Irkutsk region provided a striking visual phenomenon, revealing a substantial concentration of aerosols within Earth`s atmosphere. During the full phase of the eclipse, which commenced at 00:26:08 local time (19:26:08 Moscow time), the Moon`s disk became almost entirely invisible to observers. Curiously, this dramatic darkening of the Moon allowed for an exceptionally clear view of the Milky Way.
This remarkable observation was reported by Professor Sergey Yazev, the Director of the Astronomical Laboratory at Irkutsk State University (ISU) and a Doctor of Physical and Mathematical Sciences. Professor Yazev conducted his observations through a telescope at the Baikal Astrophysical Observatory, part of the Institute of Solar-Terrestrial Physics of the Siberian Branch of the Russian Academy of Sciences, located in Listvyanka, on the shores of Lake Baikal.
According to Professor Yazev, the near disappearance of the Moon`s disk and the simultaneous clarity of the Milky Way strongly indicate a high presence of aerosols in Earth`s atmosphere. These aerosols are fine, dispersed particles that primarily reside in the lower atmospheric layers. They play a crucial role in how sunlight, which illuminates the Moon during an eclipse, passes through the atmosphere.
Yazev suggested that this elevated aerosol content might be a consequence of recent volcanic eruptions in Kamchatka. Aerosols can be formed from various sources, including volcanic dust and ash, smoke particles from forest fires, and even terrestrial and cosmic dust. The widespread nature of these particles can significantly affect atmospheric transparency and light scattering, leading to the observed phenomena during the eclipse.
Beyond the scientific observations, Irkutsk Planetarium and the Great Irkutsk Planetarium organized a series of public events for city residents. These included an educational lecture, a full-dome film screening titled “Inhabited Moon,” and a jazz concert. Furthermore, the ISU Astronomical Observatory, in collaboration with the local planetariums, launched a competition for the best photograph of the lunar eclipse, encouraging public engagement with this celestial event.
Rupert Blackwood 
Clement Ashworth