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Flower buds in development of an elderberry Sambucus ('serenade'). Focus stack of 13 photos.

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

NASA Astronomy Picture of the Day:

The plane of our Milky Way galaxy extends beyond the limb of planet Earth in this space age exposure captured by astronaut Don Pettit. His camera, with low light and long duration settings, was pointed out the window of a Dragon crew spacecraft docked with the International Space Station on January 29. The orbital outpost was at an altitude of about 400 kilometers above the Pacific Ocean at the time. Motion blurs the Earth below, while the gorgeous view from low Earth orbit includes the Milky Way's prominent satellite galaxies, known as the Large and Small Magellanic Clouds, near the upper left in the frame. Fans of southern skies can also spot the Southern Cross. The four brightest stars of the famous southern constellation Crux are near picture center, just beyond the edge of the bright horizon and shining through Earth's orange tinted atmospheric glow.

Portrait of French author George Sand by photographer Nadar in 1864. One of the most popular writers in Europe in her lifetime, she stood up for women, criticized marriage and fought against the prejudices of a conservative society.

Nadar, Public domain, via Wikimedia Commons. View source.

NASA Astronomy Picture of the Day:

Very faint planetary nebula Abell 7 is about 1,800 light-years distant. It lies just south of Orion in planet Earth's skies toward the constellation Lepus, The Hare. Surrounded by Milky Way stars and near the line-of-sight to distant background galaxies its generally simple spherical shape, about 8 light-years in diameter, is revealed in this deep telescopic image. Within the cosmic cloud are beautiful and complex structures though, enhanced by the use of long exposures and narrowband filters that capture emission from hydrogen, sulfur, and oxygen atoms. Otherwise Abell 7 would be much too faint to be appreciated by eye. A planetary nebula represents a very brief final phase in stellar evolution that our own Sun will experience 5 billion years hence, as the nebula's central, once sun-like star shrugs off its outer layers. Abell 7 itself is estimated to be 20,000 years old. But its central star, seen here as a fading white dwarf, is some 10 billion years old.

Photo by Vikas Chander

Meerkat (Suricata suricatta) with three young in Tswalu Kalahari Reserve, South Africa.

Charles J. Sharp, CC BY-SA 4.0, via Wikimedia Commons. View source.

NASA Astronomy Picture of the Day:

Beautiful island universe Messier 94 lies a mere 15 million light-years distant in the northern constellation of the hunting dogs, Canes Venatici. A popular target for earth-based astronomers, the face-on spiral galaxy is about 30,000 light-years across, with spiral arms sweeping through the outskirts of its broad disk. But this Hubble Space Telescope field of view spans about 7,000 light-years or so across M94's central region. The sharp close-up examines the galaxy's compact, bright nucleus and prominent inner dust lanes, surrounded by a remarkable bluish ring of young, massive stars. The massive stars in the ring appear to be less than about 10 million years old, indicating the galaxy experienced a corresponding well-defined era of rapid star formation. As a result, while the small, bright nucleus is typical of the Seyfert class of active galaxies, M94 is also known as a starburst galaxy. Because M94 is relatively nearby, astronomers can explore in detail reasons for the galaxy's burst of star formation. Today's Coverage: Moon Landing

Tower of Collegium Maximum in Wrocław, Poland.

Jar.ciurus, CC BY-SA 3.0 pl, via Wikimedia Commons. View source.

NASA Astronomy Picture of the Day:

On the right, dressed in blue, is the Pleiades. Also known as the Seven Sisters and M45, the Pleiades is one of the brightest and most easily visible open clusters on the sky. The Pleiades contains over 3,000 stars, is about 400 light years away, and only 13 light years across. Surrounding the stars is a spectacular blue reflection nebula made of fine dust. A common legend is that one of the brighter stars faded since the cluster was named. On the left, shining in red, is the California Nebula. Named for its shape, the California Nebula is much dimmer and hence harder to see than the Pleiades. Also known as NGC 1499, this mass of red glowing hydrogen gas is about 1,500 light years away. Although about 25 full moons could fit between them, the featured wide angle, deep field image composite has captured them both. A careful inspection of the deep image will also reveal the star forming region IC 348 and the molecular cloud LBN 777 (the Baby Eagle Nebula). Jump Around the Universe: Random APOD Generator

Photo by Todd Anderson