Campfire Becomes Sun With Orbiting Planets

Sit around a fire. Nights are getting longer. Visible overhead should be thousands of stars, as if a handful of sand became points of light. Though sky glow mutes the stars, a few bright ones stand out early and command attention. Since ancient times, we connect dots, give them names, and create stories to explain what we see. Observe and describe--the beginnings of science.

Stars move together through the night (like the sun moves by day), except five "stars" are independent, moving against a distinct swath of background stars. We call those wanderers, like five people walking around the campfire, the planets. Again, we observe and describe. Surely the constellations that house those special stars are special themselves--the constellations of the zodiac (see another image further below).

A person walks around a campfire with enflamed marshmallow. — The planets and moon appear to move against special background constellations--the Zodiac.

One of the planets, brilliant Venus, is easy to find in late 2024 as it rises higher each night in the western sky after sunset.

Other visitors to the sky include comets; aurorae; novae; meteors ("shooting stars"), and of course, the changing moon. More campfire stories are needed to explore them.

Your 7-Star Constellation

With no direction "up", on a paper plate connect seven given stars to form your own constellation. Build a story around it. Make it yours. On the back of the plate, describe what you see.

Seven stars drawn on a paper plate. — Seven stars; no direction has to be "up".

Share stories. Use those stories to find the Big Dipper, the North Star, and the Northern Crown (Corona Borealis).

Nova in the Northern Crown

Perhaps soon, in the night sky there is likely going to be a "new" star--a nova--about as bright as Polaris, the North Star. The star is actually a faint, distant pair, where the immense gravity of a dense white dwarf star is pulling apart a companion red giant star. About every 80 years the star stuff that has built up around the white dwarf explodes, with the light brightening so much it can suddenly be seen from earth about 3,000 light years away!

Rotate your paper plate to align your 7-star constellation, even if your drawing looks upside down. One description is a Big Dipper, shown here. Pour water out of the dipper (about five times the distance of the two end stars) to find Polaris. Going the other way, follow the arc to Arcturus. Then up to the Northern Crown. Label those guides on your paper plate.

Big Dipper with arrows to two stars. — Big Dipper pours out to Polaris. Arc to Arcturus, then up to Northern Crown. .

Here's a print-friendly version of the stars.

After sunset, photograph Corona Borealis by keeping Arcturus toward the bottom of the frame. Set cell phone camera for 3 seconds. Look for "new" star (around red circle) that is about as bright as Gemma, the gem star in the northern crown.

Get "before" images now; repeat when you hear the star has blown up! The nova may not last long and it's not bright, but it's the universe unfolding.

Earth's Motions

Move away from the fire, so light is now light of the sun; in all directions are stars. A circle of people around the "sun" defines the earth's orbit. If your head is the earth, imagine you live on your nose. Stretch and inhale so you are a healthy planet.

Imagine your head is earth and you live on your nose. The swath of background constellations where sun, moon, and planets are visible is called the Zodiac. Image adapted from NMSU.

Rotate through a day; revolve around the sun for a year. Facing the sunlight is day (you can't see those seasonal stars behind the daytime sun). With your back to the light is night, and you can see those seasonal stars. Look up toward the north all year for the circumpolar stars. Stars below are underfoot, blocked by the earth itself--stars of the southern hemisphere.

As earth circles the sun and the seasons change, we assign special names to define key events. For observers in the Northern Hemisphere, celestial highlights are the winter solstice (~Dec. 21), the spring equinox (~March 21), the summer solstice (~June 21), and fall equinox (~Sept. 21).

In between those seasonal waypoints are the "cross-quarter" days: Groundhog Day (Feb. 2), May Day (May 1), Lammas (Aug. 1) and--"the most sinister cross-quarter day because it comes at a dark time of year"– Halloween (October 31).