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NASA Astronomy Picture of the Day:

The defining astronomical moment of the equinox today is at 14:46 UTC (March 20). That's when the Sun crosses the celestial equator moving north in its yearly journey through planet Earth's sky, marking the beginning of spring for our fair planet in the northern hemisphere and fall in the southern hemisphere. Then, day and night are nearly equal around the globe. In fact, both day and nighttime exposures from a spring equinox at the Observatorio del Teide in Tenerife, Canary Islands, Spain, are used in this composited skyscape. Over 1,000 images were taken with a fisheye lens and merged in the ambitious equinox project. The apparent motion of the Sun setting along the celestial equator on the equinox date follows the bright linear, diagonal track from the sequence of daytime exposures taken over 6 hours. After sunset, nighttime exposures recorded startrails, with the celestial equator as a linear track and concentric arcs circling the north celestial pole near Polaris at upper right and the south celestial pole beyond the lower left edge (and below the Teide horizon). The foreground includes the distant Teide volcano peak and the observatory's pyramid-shaped solar laboratory building.

Photo by Juan Carlos Casado

Capparis spinosa in the Ichkeul National Park. Today is the first day of spring and Tunisia's Independence Day.

IssamBarhoumi, CC BY-SA 4.0, 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.

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NASA Astronomy Picture of the Day:

ven if you live with your head in the clouds, you won’t find a jellyfish like this one very often. The featured image shows a SpaceX Falcon 9 rocket launch from Cape Canaveral in Florida on March 4. The launch happened 52 minutes before sunrise, and the second stage rocket exhaust plume was high enough in the sky to catch the light of the rising sun, while the photographer was still in the dark. This combination of light and shadow, possible at dawn or dusk, makes the exhaust, mostly water vapor and carbon dioxide, appear as a glowing cloud. It only looks like it's going down, as the rocket follows the curvature of the Earth on its way to space. A related effect is the twilight phenomenon, which causes colorful contrails sometimes mistaken for UFOs. But, in case you are wondering: real jellyfish were sent to space by NASA in the 1990s as part of a science experiment.

Photo by Michael Seeley

Saint Joseph depicted holding a staff with lily blossoms and the Christ Child on a stained-glass window in the Saint Antony church in Urtijëi. Today is St. Joseph's feast day in Western Christianity.

This Photo was taken by Wolfgang Moroder. Feel free to use my photos, but please mention me as the author and send me a message. This image is not in the public domain. Please respect the copyright protection. It may only be used according to the rules mentioned here. This specifically excludes use in social media, if applicable terms of the licenses listed here not appropriate. Please do not upload an updated image here without consultation with the Author. The author would like to make corrections only at his own source. This ensures that the changes are preserved.Please if you think that any changes should be required, please inform the author.Otherwise you can upload a new image with a new name. Please use one of the templates derivative or extract., CC BY-SA 3.0, via Wikimedia Commons. View source.

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