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NASA Astronomy Picture of the Day:

On Saturn, the rings tell you the season. On Earth, today marks an equinox, the time when the Earth's equator tilts directly toward the Sun. Since Saturn's grand rings orbit along the planet's equator, these rings appear most prominent -- from the direction of the Sun -- when the spin axis of Saturn points toward the Sun. Conversely, when Saturn's spin axis points to the side, an equinox occurs, and the edge-on rings are hard to see from not only the Sun -- but Earth. In the featured montage, images of Saturn between the years of 2020 and 2025 have been superposed to show the giant planet passing, with this year's equinox, from summer in the north to summer in the south. Yesterday, Saturn was coincidently about as close as it gets to planet Earth, and so this month the ringed giant's orb is relatively bright and visible throughout the night.

Photo by Imran Sultan

The Isaiah Scroll is the best preserved of the seven Dead Sea Scrolls that were first discovered by Bedouin shepherds from Qumran. The Dead Sea Scrolls were first made available to the public on this date in 1991.

Unknown artistUnknown artist, Public domain, via Wikimedia Commons. View source.

There are only two moments each year when the Sun lies directly above Earth’s equator. These moments are the equinoxes, when, at any location, the lengths of day and night are roughly equal. The March equinox happens sometime between March 19 and 21. The September equinox occurs sometime between September 21 and 24.
In the Northern Hemisphere, the March equinox marks the beginning of Spring and the September equinox the beginning of Fall. The reverse takes place in the Southern Hemisphere.

NASA Astronomy Picture of the Day:

Does the Sun set in the same direction every day? No, the direction of sunset depends on the time of the year. Although the Sun always sets approximately toward the west, on an equinox like tomorrow the Sun sets directly toward the west. After tomorrow's September equinox, the Sun will set increasingly toward the southwest, reaching its maximum displacement at the December solstice. Before tomorrow's September equinox, the Sun had set toward the northwest, reaching its maximum displacement at the June solstice. The featured time-lapse image shows seven bands of the Sun setting one day each month from 2019 December through 2020 June. These image sequences were taken from Alberta, Canada -- well north of the Earth's equator -- and feature the city of Edmonton in the foreground. The middle band shows the Sun setting during an equinox -- in March. From this location, the Sun will set along this same equinox band again tomorrow.

This sculpture representing the Gospel of Matthew appears in St. Genesius Church in Baden-Württemberg. It depicts a tetramorph element standing next the apostle reading a codex. Today is Saint Matthew's feast day.

Llez, CC BY-SA 3.0, via Wikimedia Commons. View source.

NASA Astronomy Picture of the Day:

rly risers around planet Earth have enjoyed a shining crescent Moon near brilliant Venus, close to the eastern horizon in recent morning twilight skies. And yesterday, on September 19, skygazers watching from some locations in Earth's northern hemisphere were also able to witness Venus, in the inner planet's waxing gibbous phase, pass behind the Moon's waning crescent. In fact, this telescopic snapshot was taken moments before that occultation of gibbous Venus by the crescent Moon began. The close-up view of the beautiful celestial alignment records Venus approaching part of the Moon's sunlit edge in clear daytime skies from the Swiss Alps. Tomorrow, the Sun will pass behind a New Moon. But to witness that partial solar eclipse on September 21, skygazers will need to watch from locations in planet Earth's southern hemisphere.

Photo by Luca Bartek

Paesens. Dobbe (Little lake) behind the sea wall.

Agnes Monkelbaan, CC BY-SA 4.0, via Wikimedia Commons. View source.

NASA Astronomy Picture of the Day:

A study in contrasts, this colorful cosmic skyscape features stars, dust, and glowing gas in the vicinity of NGC 6914. The interstellar complex of nebulae lies some 6,000 light-years away, toward the high-flying northern constellation Cygnus and the plane of our Milky Way Galaxy. Obscuring interstellar dust clouds appear in silhouette while reddish hydrogen emission nebulae, along with the dusty blue reflection nebulae, fill the cosmic canvas. Ultraviolet radiation from the massive, hot, young stars of the extensive Cygnus OB2 association ionize the region's atomic hydrogen gas, producing the characteristic red glow as protons and electrons recombine. Embedded Cygnus OB2 stars also provide the blue starlight strongly reflected by the dust clouds. The over one degree wide telescopic field of view spans about 100 light-years at the estimated distance of NGC 6914.

Photo by Tommy Lease