Night Sky: April 2021

6th: Conjunction of the Moon and Saturn (figure 1). Visible in the dawn sky, appearing at 05:46 (BST), 1 hour, 55 minutes before the Sun, and attaining an altitude of 10° above the South, Eastern horizon before fading from view as dawn breaks approximately 06:18. Visible to the unaided eye or with binoculars. Known as an appulse, it is when two or more astronomical objects, usually the planets or the Moon, appear close to one another in the sky. The Moon will be 385430 km from Earth, while Saturn will be 1549.3 million km distant.

Figure 1: Conjunction of Moon and Saturn.

17th: Conjunction of Moon and Mars (figures 2 & 3)). Becoming visible approximately 21:38 (BST) as dusk sky fades above Western horizon, setting approximately 01:49. Visible to the unaided eye or through binoculars.

The Moon will be 397119 km from Earth and Mars will be 285.8 million km from Earth.

Figure 2: Conjunction of Moon and Mars.

Figure 3.

22nd: Lyrid meteor shower (figure 4 & 5). Active from 16thto 25th. Visible inconstellation Hercules. Radiant point above the horizon all night, meaning the shower will be active during the hours of darkness. Expected peak activity at 13:00 (BST) on 22nd, so best displays might be seen before dawn and after dusk on 22nd. Upto 18 meteors per hour is possible.

Figure 4: Image of Lyrid meteor shower.

Figure 5: Lyrid meteor shower.

27th: Moon reaching full phase (figure 6 & 7). Almost directly opposite the Sunin the sky. It will be close to the time of month when the Moon makes its closest approach to Earth (perigee). The Moon will appear slightly larger and brighter than other times, however, any difference is imperceptible to the unaided eye. Perigee full Moons such as this occur approximately once every 13 months.

It will be 356587 km to 357378 km from Earth. April full Moon is called the pink Moon, named after phlox, the pink flowers that bloom in spring.

Figure 6: Moon phases.

Figure 7: Pink Moon.

1st to 30th: Figure 8 to16 show some of the constellations that will be on view during the month of April.

Figure 8.

Figure 9.

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figures 9 to 16 are: Antlia, Chamaeleon, Crater, Hydra, Leo, Leo Minor, Sextans and Ursa Major respectively.

WARNING: Never attempt to view through binoculars, telescope or any optical aid an object near to the Sun. Also, never attempt to view the Sun, aided or unaided, doing so may result in immediate and permanent blindness. Always use astronomical approved viewing equipment.

The Stellarium software will assist greatly in locating objects in the sky.

Mark R Smith FRAS FRi


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