Q and A with the experts: The universe in motion

Science

Mercury will be visible in the night sky only during the last week of February

This February, the night sky is putting on a show with a grand planet parade that will have a seven-planet alignment ! We asked Dr. Roan Haggar, a postdoctoral fellow and the outreach coordinator for the Waterloo Centre for Astrophysics (WCA) at the University of Waterloo, to share the science behind February’s grand plane t parade so we can better understand the universe in motion.

A planet parade occurs when multiple planets are visible in the sky from our perspective on Earth. Each planet in our Solar System orbits the Sun in the same plane but at different speeds. Of course, Earth orbits the Sun in 365 days, but Mercury completes its orbit in 88 days while Neptune takes 60,190 days, which is the equivalent 165 years on Earth !

Because each planet has its own orbit, i t’is rare for planets to be on the same side of the Sun and appear in the night sky together. During a clear night this February, Venus, Saturn, Jupiter, and Mars will be shining bright, visible to the naked eye, while Uranus and Neptune can be seen with a telescope. But the real highlight? Only during the last week of February will you be able to see Mercury completing the grand planet parade !  

When s kygazing , the easiest way to tell a planet from a star is by its light. Stars generate their light and appear to twinkle while planets only reflect the Sun’s light and shine with a steady, unwavering glow. While the best day s to view e grand parade during the last week of February (weather p ermitting ) , you can step outside on any clear night in February to see an alignment of planets as soon as the Sun sets!

• Mercury : M aking a brief appearance near the horizon at the end of the month, Mercury will be at its brightest just as the sunset fades.
• Venus : T he brightest of them all, Venus will shine in the west after sunset throughout the month.
• Mars : L ook east for its distinctive amber-orange hue as it climbs high into the night.
• Jupiter : H igh in the sky, Jupiter will radiate with a steady, bright glow.
• Saturn : C atch it low in the western sky during the first hour after sunset before it slips below the horizon.
• Uranus and Neptune : U s’e a telescope and a stargazing app to find the two planets farthest away from Earth.