Yukon Sky Report – April 2024
By: Shale Davis

Solar Eclipse

The upcoming total solar eclipse on April 8th has no doubt captured the attention of many. This is the first total eclipse to pass over North America since 2017. Many are travelling to the line of totality to experience the very best that this cosmic occurrence can offer. Unfortunately, due to our position in the Yukon only a small portion of the Sun will be obstructed by the Moon, (about 4% of its surface area). This can still be interesting to observe, with the solar disc appearing to be “cropped.” It is important to note that some kind of solar filter is essential to observe this partial eclipse safely and effectively. Solar glasses, from a reputable dealer, are a viable option, and of course telescope users with a matching solar filter can have great views. If you happen to own a welding mask, this can be used but only if it can be dimmed to shade 12 or darker. Regardless of your preferred viewing method the eclipse will be at its best at 11:35 AM on April 8th.

Instructions on how to find the Sun in the sky not included.

The Moon

This month the Moon will be sticking close to the southern horizon, never rising particularly high into the sky. It will reach new moon on the 8th, not coincidentally the same date as the eclipse. It will then grow until full moon on the 23rd.

The Planets

Jupiter – Now being the only readily visible planet in the night sky, Jupiter remains a potential target, though not for much longer. It can be seen shortly following sunset to the east. Be sure to look out for its moon and cloud formations. 

T Coronae Borealis Nova

Tucked away in the Corona Borealis constellation lies a seemingly inconspicuous star not even visible to the unaided eye. This is T Coronae Borealis, and it is in fact two stars (though they appear as only one) orbiting each other in violent dance. The larger component of the binary system is a massive Red Giant near the end of its life. The smaller member is an incredibly dense White Dwarf, (A stellar ember composed of electron degenerate matter). This White dwarf is gravitational stealing matter directly from the surface of its giant neighbour, creating an accretion (a ring of material orbiting its host). During outbursts the rate of transfer between the two stars increases dramatically, thus increasing the luminosity of the system. The last such outburst was in 1946 in which it temporarily brightened to magnitude +3, easily visible to the unaided eye. Another such outburst is anticipated some time between now and the end of summer.

Clear Skies!