Land & Sky
TELESCOPE VIEWING:
Seeing the Universe with One's Own Eyes
by Judith Frey
Twinkle, twinkle little star . . . what wonders lie beyond you in the heavens, so far?
It's amazing to discover what lies just beyond our sight in the night sky—stunning visions that are available to us because of the optics invented by Galileo and Newton. With even a small telescope, you can discern structures that are more delicate than anything seen on earth. Millions of stars on the edge of a galaxy's spiral arms look, to our eyes, like the finest diffusion of light to strike the retina. An active galaxy with a jet streaming into space at nearly the speed of light is perceived by us, millions of light-years away, as stillness. A star-forming nebula reveals new stars that are blowing gas and dust away from them. A hot young star shines with the most luminous blue you've ever seen.
When we observe the phenomena of the universe with our own eyes, it is
an aesthetic experience, one that touches the spirit. Complete darkness allows
us to see. Our eyes take about half an hour to adapt to the dark--so the longer
we look, the more we are able to see. The transcendent experience of night that was such a part of our ancestors' lives is still possible today. With this in mind, Snowmass is applying for the designation of Dark Sky Community under the International Dark Sky Association. With a program of education, we are
encouraging residents to make the necessary adjustments to their outdoor
lighting that will protect the night sky as well as the natural patterns of animal life.
Several activities are planned for the coming year--a community star party,
astrophotography demonstrations, and a tentative trip to the MacDonald
Observatory in West Texas for a night or two of spectacular viewing on the 82-
inch telescope. For more information, contact judy@ionsky.com or 970-922-
8001.
Yearly Solar Events 2025
By Judith Frey
January
On January 4, at 6:28 AM, the earth reaches its closest point to the sun for the
year (perihelion), 91.4 million miles. Our orbit around the sun is slightly elliptical
due to the movement of the moon and other planets. The word perihelion is from
the ancient Greek, meaning “close to the sun.” The earth is farthest from the sun in
July (aphelion). See Notes (below).
The latest sunrise of the year occurs on January 4 at 7:19 AM. The days have been
lengthening almost imperceptibly since the solstice on December 21, but from now
on the daylight is increasing in the morning as well as the evening.
March
The spring (vernal) equinox is March 20 at 10:01 AM. The sun is directly over the
equator at noon, and it rises due east and sets due west. The length of the day has
been increasing more and more rapidly since the winter solstice, to a rate of
change of about 5 minutes per day.
June
The earliest sunrise of the year is on June 14, at 5:30 AM.
June 21 is the summer solstice, the longest day of the year. At about 4:42 AM, the
north pole is tilted the closest to the sun. The sun’s angle relative to earth’s equator
changes so gradually around the solstices that the difference is almost
imperceptible for about ten days. This means that the sun rises and sets,
respectively, in the same places on the horizon during that period. The word
solstice is derived from the Latin solstitium, a combination of sol, “the sun,”
and sistere, “to make stand, stand still.” The length of the day now is slightly more
than 14 hours, 55 minutes.
June 27 is the day of the latest sunset of the year, at 8:33 PM. After this, the long
summer twilight begins to shorten very gradually.
July
On July 3, the earth reaches its aphelion, the farthest point from the sun, at 1:54
PM. At that time, the sun and earth are separated by some 94.5 million miles--
while the average distance is around 93 million miles.
September
The fall (autumnal) equinox is September 22 at 8:19 PM; now the days and nights
are nearly equal in length. The rate of change is very rapid now; the days are
getting shorter faster and the light is dimming noticeably.
December
The year’s earliest sunset is on Dec. 7, at 4:44 PM. Every year I raise a glass and
offer a toast to the setting sun, for soon there will be more light in the early evening!
The winter solstice, the first day of winter, is Dec. 21 at 4:03 PM. At this time, the
south pole is tilted closest to the sun. This night is the longest of the year and the
day is the shortest, with about 9 hours and 25 minutes of daylight in Colorado.
New Year’s Eve, Dec. 31, is an astronomical celebration of sorts—at midnight, the
brightest star in the sky, Sirius, reaches its highest point for the entire year!
Notes: The orbit of the earth around the sun varies due to the gravitational influences of
other planetary objects, particularly the moon. Approximately every 100,000 years, the earth's
orbital path changes from being nearly circular to elliptical.
The length of a solar day is not exactly 24 hours long. It varies throughout the year because
of the elliptical shape of earth's orbit and its axial tilt. It is longer than 24 hours around the
summer and winter solstices and shorter than 24 hours around the spring (vernal) and fall
(autumnal) equinoxes.
On most days, solar noon does not occur at the same time as noon on a clock. On December
21, 2024—the day of the Northern Hemisphere winter solstice—solar noon is at 11:54 AM. On
January 3, 2025, the first day of the latest sunrise, solar noon takes place 6 minutes later, at
12:00 noon. The following day, January 4, solar noon falls at 12:01, and keeps getting later
until February 11. This is why a location's earliest sunset occurs before, and its latest sunrise
occurs after, the winter solstice.