APOD: Titan: Moon over Saturn (5/27/22)

Like Earth’s moon, Saturn’s largest moon Titan is locked in synchronous rotation. This mosaic of images recorded by the Cassini spacecraft in May of 2012 shows its anti-Saturn side, the side always facing away from the ringed gas giant. The only moon in the solar system with a dense atmosphere, Titan is the only solar system world besides Earth known to have standing bodies of liquid on its surface and an earthlike cycle of liquid rain and evaporation. Its high altitude layer of atmospheric haze is evident in the Cassini view of the 5,000 kilometer diameter moon over Saturn’s rings and cloud tops. Near center is the dark dune-filled region known as Shangri-La. The Cassini-delivered Huygens probe rests below and left of center, after the most distant landing for a spacecraft from Earth.

Magnificent spiral galaxy NGC 4565 is viewed edge-on from planet Earth. Also known as the Needle Galaxy for its narrow profile, bright NGC 4565 is a stop on many telescopic tours of the northern sky, in the faint but well-groomed constellation Coma Berenices. This sharp, colorful image reveals the galaxy’s boxy, bulging central core cut by obscuring dust lanes that lace NGC 4565’s thin galactic plane. NGC 4565 itself lies about 40 million light-years distant and spans some 100,000 light-years. Easily spotted with small telescopes, sky enthusiasts consider NGC 4565 to be a prominent celestial masterpiece Messier missed.

APOD: NGC 4565: Galaxy on Edge (5/26/22)

© Michael Sherick

APOD: The Lively Center of the Lagoon Nebula (5/25/22)

The center of the Lagoon Nebula is a whirlwind of spectacular star formation. Visible near the image center, at least two long funnel-shaped clouds, each roughly half a light-year long, have been formed by extreme stellar winds and intense energetic starlight. A tremendously bright nearby star, Herschel 36, lights the area. Vast walls of dust hide and redden other hot young stars. As energy from these stars pours into the cool dust and gas, large temperature differences in adjoining regions can be created generating shearing winds which may cause the funnels. This picture, spanning about 10 light years, combines images taken in six colors by the orbiting Hubble Space Telescope. The Lagoon Nebula, also known as M8, lies about 5000 light years distant toward the constellation of the Archer (Sagittarius). Almost hyperspace: Random APOD Generator

APOD: A Deep Sky Behind an Eclipsed Moon (5/24/22)

The plan was to capture a picturesque part of the sky that was hosting an unusual guest. The result included a bonus — an additional and unexpected guest. The beautiful background features part of the central band of our Milky Way galaxy on the far left, and the colorful clouds of Rho Ophiuchi in the image center. The unusual guest, a dimmed and reddened Moon on the right, was expected because the image was taken during last week’s total lunar eclipse. The timing had to be right because the Moon — both before and after eclipse — would be so bright it would overwhelm the background. The unexpected guest was the bright meteor across the image center. The fleeting meteor streak was captured on only one of the 10 consecutively-captured deep-field images from La Palma in the Spanish Canary Islands, while the eclipsed Moon image was taken immediately afterwards with the same camera and from the same location. The next total lunar eclipse — also quite expected — will occur in early November. Notable Submissions to APOD: Total Lunar Eclipse of 2022 May

© Andrei Ionut Dascalu

APOD: The Once and Future Stars of Andromeda (5/23/22)

This picture of Andromeda shows not only where stars are now, but where stars will soon be. Of course, the big, beautiful Andromeda Galaxy, M31, is a spiral galaxy — and a mere 2.5 million light-years away. Both space-based and ground-based observatories have been here combined to produce this intriguing composite image of Andromeda, at wavelengths both inside and outside normally visible light. The visible light shows where M31’s stars are now — as highlighted in white and blue hues and imaged by the Hubble, Subaru, and Mayall telescopes. The infrared light shows where M31’s future stars will soon form — as highlighted in orange hues and imaged by NASA’s Spitzer Space Telescope. The infrared light tracks enormous lanes of dust, warmed by stars, sweeping along Andromeda’s spiral arms. This dust is a tracer of the galaxy’s vast interstellar gas — the raw material for future star formation. These new stars will likely form over the next hundred million years, surely well before Andromeda merges with our Milky Way Galaxy in about 5 billion years.

APOD: A Large Tsunami Shock Wave on the Sun (5/22/22)

Tsunamis this large don’t happen on Earth. During 2006, a large solar flare from an Earth-sized sunspot produced a tsunami-type shock wave that was spectacular even for the Sun. Pictured here, the tsunami wave was captured moving out from active region AR 10930 by the Optical Solar Patrol Network (OSPAN) telescope in New Mexico, USA. The resulting shock wave, known technically as a Moreton wave, compressed and heated up gasses including hydrogen in the photosphere of the Sun, causing a momentarily brighter glow. The featured image was taken in a very specific red color emitted exclusively by hydrogen gas. The rampaging tsunami took out some active filaments on the Sun, although many re-established themselves later. The solar tsunami spread at nearly one million kilometers per hour, and circled the entire Sun in a matter of minutes.

© Donald Waid

Very faint planetary nebula Abell 7 is some 1,800 light-years distant, just south of Orion in planet Earth’s skies in 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 outlined in this deep telescopic image. Within its confines are beautiful, more complex details enhanced by the use of narrowband filters. Emission from hydrogen is shown in reddish hues with oxygen emission mapped to green and blue colors, giving Abell 7 a natural appearance that would otherwise 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. Its central star is seen here as a fading white dwarf some 10 billion years old.

APOD: Planetary Nebula Abell 7 (5/21/22)

APOD: A View from Earth’s Shadow (5/20/22)

© Maxime Oudoux

This serene sand and skyscape finds the Dune of Pilat on the coast of France still in Earth’s shadow during the early morning hours of May 16. Extending into space, the planet’s dark umbral shadow covered the Moon on that date. From that location the total phase of a lunar eclipse had begun before moonset. Still in sunlight though, the International Space Station crossed from the western horizon and Earth’s largest artificial moon traced the bright flat arc through the sky over 400 km above. Simply constructed, the well-planned panoramic scene was captured over a 5 minutes in a series of consecutive images.

APOD: A Digital Lunar Eclipse (5/19/22)

Recorded on May 15/16 this sequence of exposures follows the Full Moon during a total lunar eclipse as it arcs above treetops in the clearing skies of central Florida. A frame taken every 5 minutes by a digital camera shows the progression of the eclipse over three hours. The bright lunar disk grows dark and red as it glides through planet Earth’s shadow. In fact, counting the central frames in the sequence measures the roughly 90 minute duration of the total phase of this eclipse. Around 270 BC, the Greek astronomer Aristarchus also measured the duration of total lunar eclipses, but probably without the benefit of digital watches and cameras. Still, using geometry he devised a simple and impressively accurate way to calculate the Moon’s distance in terms of the radius of planet Earth, from the eclipse duration.

© Michael Cain

APOD: A Jewel on the Flower Moon (5/18/22)

© Tomas Slovinsky

Cloudy skies plagued some sky watchers on Sunday as May’s Full Flower Moon slipped through Earth’s shadow in a total lunar eclipse. In skies above Chile’s Atacama desert this telephoto snapshot still captured an awesome spectacle though. Seen through thin high cirrus clouds just before totality began, a last sliver of sunlit crescent glistens like a hazy jewel atop the mostly shadowed lunar disk. This full moon was near perigee, the closest point in its elliptical orbit. It passed near the center of Earth’s dark umbral shadow during the 90 minute long total eclipse phase. Faintly suffused with sunlight scattered by the atmosphere, the umbral shadow itself gave the eclipsed moon a reddened appearance and the very dramatic popular moniker of a Blood Moon.