Enceladus by Saturnshine
Image Credit: NASA; ESA, JPL, Cassini Imaging Team, SSI; Color Composite: Gordan Ugarkovic
Explanation: This moon is shining by the light of its planet. Specifically, a large portion of Enceladus pictured here is illuminated primarily by sunlight first reflected from the planet Saturn. The result is that the normally snow-white moon appears in the gold color of Saturn’s cloud tops. As most of the illumination comes from the image left, a labyrinth of ridges throws notable shadows just to the right of the image center, while the kilometer-deep canyon Labtayt Sulci is visible just below. The bright thin crescent on the far right is the only part of Enceladus directly lit by the Sun. The featured image was taken in 2011 by the robotic Cassini spacecraft during a close pass by by the enigmatic moon. Inspection of the lower left part of this digitally sharpened image reveals plumes of ice crystals thought to originate in a below-surface sea.
Tomorrow’s picture: stars and dust
NGC 2626 along the Vela Molecular Ridge
Image Credit & Copyright: Mike Selby & Mark Hanson
Explanation: Centered in this colorful cosmic canvas, NGC 2626 is a beautiful, bright, blue reflection nebula in the southern Milky Way. Next to an obscuring dust cloud and surrounded by reddish hydrogen emission from large H II region RCW 27 it lies within a complex of dusty molecular clouds known as the Vela Molecular Ridge. NGC 2626 is itself a cloud of interstellar dust reflecting blue light from the young hot embedded star visible within the nebula. But astronomical explorations reveal many other young stars and associated nebulae in the star-forming region. NGC 2626 is about 3,200 light-years away. At that distance this telescopic field of view would span about 30 light-years along the Vela Molecular Ridge.
Tomorrow’s picture: moon by planetlight
Reflections on the 1970s
Image Credit & Copyright: Daniel Stern
Explanation: The 1970s are sometimes ignored by astronomers, like this beautiful grouping of reflection nebulae in Orion – NGC 1977, NGC 1975, and NGC 1973 – usually overlooked in favor of the substantial glow from the nearby stellar nursery better known as the Orion Nebula. Found along Orion’s sword just north of the bright Orion Nebula complex, these reflection nebulae are also associated with Orion’s giant molecular cloud about 1,500 light-years away, but are dominated by the characteristic blue color of interstellar dust reflecting light from hot young stars. In this sharp color image a portion of the Orion Nebula appears along the bottom border with the cluster of reflection nebulae at picture center. NGC 1977 stretches across the field just below center, separated from NGC 1973 (above right) and NGC 1975 (above left) by dark regions laced with faint red emission from hydrogen atoms. Taken together, the dark regions suggest the region’s popular moniker, the Running Man Nebula. At the estimated distance of Orion’s dusty molecular cloud this running man would be about 15 light-years across.
Tomorrow’s picture: pixels in space
The Seventh World of Trappist-1
Illustration Credit & Copyright: Michael Carroll
Explanation: Seven worlds orbit the ultracool dwarf star TRAPPIST-1. A mere 40 light-years away, many of the exoplanets were discovered in 2016 using the Transiting Planets and Planetesimals Small Telescope (TRAPPIST) located in the Atlas Mountains of Morocco, and later confirmed with telescope including NASA’s Spitzer Space Telescope. The TRAPPIST-1 planets are likely all rocky and similar in size to Earth, and so compose one of the largest treasure troves of terrestrial planets ever detected around a single star. Because they orbit very close to their faint, tiny star they could also have regions where surface temperatures allow for the presence of ice or even liquid water, a key ingredient for life. Their tantalizing proximity to Earth makes them prime candidates for future telescopic explorations of the atmospheres of potentially habitable planets. All seven exoplanets appear in the featured illustration, which imagines a view from the most distant known world of this system, TRAPPIST-1h, as having a rocky landscape covered in ice. Meanwhile, in the imagined background, one of the system’s inner planets crosses in front of the dim, orange, nearly Jupiter-sized parent star.
Tomorrow’s picture: open space
A Triple View of Comet ZTF
Image Credit & Copyright: Javier Caldera & Miguel Gracia
Explanation: Comet ZTF has a distinctive shape. The now bright comet visiting the inner Solar System has been showing not only a common dust tail, ion tail, and green gas coma, but also an uncommonly distinctive antitail. The antitail does not actually lead the comet — it is just that the head of the comet is seen superposed on part of the fanned-out and trailing dust tail. The giant dirty snowball that is Comet C/2022 E3 (ZTF) has now passed its closest to the Sun and tomorrow will pass its closest to the Earth. The main panel of the featured triple image shows how Comet ZTF looked last week to the unaided eye under a dark and clear sky over Cáceres, Spain. The top inset image shows how the comet looked through binoculars, while the lower inset shows how the comet looked through a small telescope. The comet is now visible all night long from northern latitudes but will surely fade from easy observation during the next few weeks.
Tomorrow’s picture: planets real and imagined
Globular Star Cluster NGC 6355 from Hubble
Image Credit: ESA/Hubble & NASA, E. Noyola, R. Cohen
Explanation: Globular clusters once ruled the Milky Way. Back in the old days, back when our Galaxy first formed, perhaps thousands of globular clusters roamed our Galaxy. Today, there are less than 200 left. Over the eons, many globular clusters were destroyed by repeated fateful encounters with each other or the Galactic center. Surviving relics are older than any Earth fossil, older than any other structures in our Galaxy, and limit the universe itself in raw age. There are few, if any, young globular clusters left in our Milky Way Galaxy because conditions are not ripe for more to form. The featured image shows a Hubble Space Telescope view of 13-billion year old NGC 6355, a surviving globular cluster currently passing near the Milky Way’s center. Globular cluster stars are concentrated toward the image center and highlighted by bright blue stars. Most other stars in the frame are dimmer, redder, and just coincidently lie near the direction to NGC 6355.
Tomorrow’s picture: tails tales
Barnard 68: Dark Molecular Cloud
Image Credit: FORS Team, 8.2-meter VLT Antu, ESO
Explanation: Where did all the stars go? What used to be considered a hole in the sky is now known to astronomers as a dark molecular cloud. Here, a high concentration of dust and molecular gas absorb practically all the visible light emitted from background stars. The eerily dark surroundings help make the interiors of molecular clouds some of the coldest and most isolated places in the universe. One of the most notable of these dark absorption nebulae is a cloud toward the constellation Ophiuchus known as Barnard 68, pictured here. That no stars are visible in the center indicates that Barnard 68 is relatively nearby, with measurements placing it about 500 light-years away and half a light-year across. It is not known exactly how molecular clouds like Barnard 68 form, but it is known that these clouds are themselves likely places for new stars to form. In fact, Barnard 68 itself has been found likely to collapse and form a new star system. It is possible to look right through the cloud in infrared light.
Tomorrow’s picture: bright marking on the sky
Comet ZTF over Mount Etna
Image Credit & Copyright: Dario Giannobile
Explanation: Comet-like plumes are blowing over the volcanic peaks of Mount Etna in this wintry mountain-and-skyscape from planet Earth. The stacked and blended combination of individual exposures recorded during the cold night of January 23, also capture naked-eye Comet ZTF just above Etna’s snowy slopes. Of course increasing sunlight and the solar wind are responsible for the comet’s greenish coma and broad dusty tail. This weekend Comet ZTF is dashing across northern skies between north star Polaris and the Big Dipper. From a dark site you can only just spot it as a fuzzy patch though. That’s still an impressive achievement if you consider you are gazing at a visitor from the distant Oort cloud with your own eyes. But binoculars or a small telescope will make for an even more enjoyable view of this Comet ZTF in the coming days.
Tomorrow’s picture: dark marking on the sky
Comet ZTF: Orbital Plane Crossing
Image Credit & Copyright: Dan Bartlett
Explanation: The current darling of the northern night, Comet C/2022 E3 ZTF is captured in this telescopic image from a dark sky location at June Lake, California. Of course Comet ZTF has been growing brighter in recent days, headed for its closest approach to Earth on February 1. But this view was recorded on January 23, very close to the time planet Earth crossed the orbital plane of long-period Comet ZTF. The comet’s broad, whitish dust tail is still curved and fanned out away from the Sun as Comet ZTF sweeps along its orbit. Due to perspective near the orbital plane crossing, components of the fanned out dust tail appear on both sides of the comet’s green tinted coma though, to lend Comet ZTF a visually striking (left) anti-tail. Buffeted by solar activity the comet’s narrower ion tail also streams away from the coma diagonally to the right, across the nearly three degree wide field of view.
Tomorrow’s picture: over the mountain
Active Galaxy NGC 1275
Image Credit: NASA, ESA, Hubble Heritage, A. Fabian (University of Cambridge, UK)
Explanation: Active galaxy NGC 1275 is the central, dominant member of the large and relatively nearby Perseus Cluster of Galaxies. Wild-looking at visible wavelengths, the active galaxy is also a prodigious source of x-rays and radio emission. NGC 1275 accretes matter as entire galaxies fall into it, ultimately feeding a supermassive black hole at the galaxy’s core. This color composite image made from Hubble Space Telescope data recorded during 2006. It highlights the resulting galactic debris and filaments of glowing gas, some up to 20,000 light-years long. The filaments persist in NGC 1275, even though the turmoil of galactic collisions should destroy them. What keeps the filaments together? Observations indicate that the structures, pushed out from the galaxy’s center by the black hole’s activity, are held together by magnetic fields. Also known as Perseus A, NGC 1275 spans over 100,000 light years and lies about 230 million light years away.
Tomorrow’s picture: pixels in space