aurora
In the far north, night skies are often decorated with shimmering bands and curtains of color: the
aurora borealis.
It’s here where charged particles streaming from the Sun interact with particles in our atmosphere, charging them up and creating strange phenomena such as the
aurora and geomagnetic storms.
celestial
Jupiter continues to be a source of fascination for astronomers, with NASA's Juno probe continuously orbiting the
celestial giant since 2016.
constellation
Do you see the word
stella in the middle of
constellation? That's Latin for "star." Winter is an excellent time for stargazing, since cold air tends to be dry and clear. Ancient people navigated and marked the seasons with the movements of stars. How many
constellations can you name?
The
constellations glittered in the black sky, a star streaking across it like a shimmering loose thread.
crepuscular
"Evening" is a nice enough word, but "twilight" is more descriptive. To say that something is
crepuscular, from the Latin
crepusculum, is an even more interesting way to describe the beginning of night.
Here are 10 books to shed some light into such
crepuscular operations.
dusk
Dusk is another useful word for the time after the sun goes down but before nightfall.
We trudged up the hill to the summit in the enveloping
dusk.
equinox
While summer and winter begin on
solstices, spring and fall start on
equinoxes.
Equinox literally means "equal night;" these two days mark the periods exactly between the solstices, where day and night are equal length.
Co-opted by the Catholic Church as “All Hallows’ Day” or “All Saints’ Day,” Samhain lands midway between the fall
equinox and the winter solstice, celebrated on the evening of Oct.
hemisphere
Because the Earth's axis is tilted at 23 degrees relative to the ecliptic, its orbital plane, whichever
hemisphere is tilted away from the sun experiences winter since the sun appears much lower in the sky and warms the planet's surface less than in summer.
Oxygen rose during each northern
hemisphere spring and then fell in the autumn.
hibernal
Hibernal is the opposite of
estival, meaning "summery." It comes from the Latin
hibernus, also meaning "wintery," the same root where
hibernate comes from.
The winter, or
hibernal, solstice — which is actually only a single moment in time astronomically — is celebrated in various ways throughout the world but often includes an observation at sunrise or sunset.
nadir
On the winter solstice, the noonday sun reaches its lowest point of the year, its
nadir.
For the last five months, the Washington Nationals, baseball’s greatest underachievers at their
nadir in late May, thrived when left for dead.
nocturnal
See that
noc there at the beginning of
nocturnal? That's the same Latin root that gives us
equinox.
“We’re saying, look, light pollution is also a huge driver, especially with
nocturnal insects.”
solstice
solstice comes from the Latin
sol, "sun," and
sistere, "to stand still." The summer and winter
solstices are the days where the sun reaches its highest and lowest points respectively.
There was only six hours of daylight now, the pink low-horizon
solstice light barely creeping over the high mountain walls.
zenith
The
zenith is the opposite of
nadir, so on the winter solstice in the northern hemisphere, it's the first day of summer down south: the longest day, with the sun reaching its highest point at noon.
It reached what they were certain must be the
zenith of its curve, and then, defying all reason, it continued to rise into the air.
zodiac
The course began with the meanings of the
zodiac, from Aries to Aquarius.