Move over Hubble -- here comes the James Webb Space Telescope (JWST). JWST promises to be the new most powerful telescope in space. In the last month, the 18-segment gold-plated primary mirror for JWST was unveiled. In the featured time-lapse video taken last week, the 6.5-meter diameter mirror was raised to a vertical position. The dramatic 30-second sequence shows NASA engineers monitoring the test as room lights glint brightly off the mirror's highly reflective surface. The beryllium mirrors have been coated with a thin film of gold to make them more reflective to infrared light. The science goals of JWST include studying the workings of the early universe and the properties of planets orbiting nearby stars. Because of the mirror's great size, it will be folded for launch and then, assuming all goes as planned, dramatically unfolded again in space. The JWST, a joint mission of the space agencies of the USA, Europe, and Canada, is currently scheduled to be launched in late 2018. NASA Coverage: Today's Transit of Mercury across the Sun
2016-05-09💙 Add To Favorites
Look through the cosmic cloud cataloged as NGC 281 and you might miss the stars of open cluster IC 1590. Still, formed within the nebula that cluster's young, massive stars ultimately power the pervasive nebular glow. The eye-catching shapes looming in this portrait of NGC 281 are sculpted columns and dense dust globules seen in silhouette, eroded by intense, energetic winds and radiation from the hot cluster stars. If they survive long enough, the dusty structures could also be sites of future star formation. Playfully called the Pacman Nebula because of its overall shape, NGC 281 is about 10,000 light-years away in the constellation Cassiopeia. This sharp composite image was made through narrow-band filters, combining emission from the nebula's hydrogen, sulfur, and oxygen atoms in green, red, and blue hues. It spans over 80 light-years at the estimated distance of NGC 281.
2017-09-30 Eric Coles💙 Add To Favorites
How did those big rocks end up on that strange terrain? One of the more unusual places here on Earth occurs inside Death Valley, California, USA. There a dried lakebed named Racetrack Playa exists that is almost perfectly flat, with the odd exception of some very large stones, one of which is pictured above. Now the flatness and texture of large playa like Racetrack are fascinating but not scientifically puzzling -- they are caused by mud flowing, drying, and cracking after a heavy rain. Only recently, however, has a viable scientific hypothesis been given to explain how 300-kilogram stones ended up near the middle of such a large flat surface. Unfortunately, as frequently happens in science, a seemingly surreal problem ends up having a relatively mundane solution. It turns out that high winds after a rain can push even heavy rocks across a momentarily slick lakebed.
2002-04-10 Joe Orman💙 Add To Favorites
A year in sunsets, from April 2023 to March 2024, track along the western horizon in these stacked panoramic views. The well-planned sequence is constructed of images recorded near the 21st day of the indicated month from the same location overlooking Cairo, Egypt. But for any location on planet Earth the yearly extreme northern (picture right) and southern limits of the setting Sun mark the solstice days. The word solstice is from Latin for "Sun" and "stand still". On the solstice date the seasonal drift of the Sun's daily path through the sky appears to pause and reverse direction in its annual celestial journey. Of course the Sun reaches a stand still on today's date. The 21 December 2024 solstice at 09:21 UTC is the moment of the Sun's southernmost declination, the start of astronomical winter in the north and summer in the south.
2024-12-21 Wael Omar💙 Add To Favorites
What's that strange light down the road? Dust orbiting the Sun. At certain times of the year, a band of sun-reflecting dust from the inner Solar System appears prominently just after sunset -- or just before sunrise -- and is called zodiacal light. Although the origin of this dust is still being researched, a leading hypothesis holds that zodiacal dust originates mostly from faint Jupiter-family comets and slowly spirals into the Sun. Recent analysis of dust emitted by Comet 67P, visited by ESA's robotic Rosetta spacecraft, bolsters this hypothesis. Pictured when climbing a road up to Teide National Park in the Canary Islands of Spain, a bright triangle of zodiacal light appeared in the distance soon after sunset. Captured on June 21, 2019, the scene includes bright Regulus, the alpha star of the constellation Leo, standing above center toward the left. The Beehive Star Cluster (M44) can be spotted below center, closer to the horizon and also immersed in the zodiacal glow.
2025-08-10 Ruslan Merzlyakov (astrorms)💙 Add To Favorites
A fast and powerful wind from a hot young star has created this stunning bubble-shaped nebula poised on the end of a bright filament of hydrogen gas. Cataloged as N44F, the cosmic windblown bubble is seen at the left of this Hubble Space Telescope image. N44F lies along the northern outskirts of the N44 complex of emission nebulae in the Large Magellanic Cloud, a mere 160,000 light-years away. The bright, blue, hot star itself is just below the center of the bubble. Peering into the bubble's interior, the Hubble image reveals dramatic structures, including pillars of dust, aligned toward N44F's hot central star. Reminiscent of dust pillars in stellar nurseries within our Milky Way galaxy, they likely contain young stars at their tips. Expanding into the surrounding gas and dust at about 12 kilometers per second, N44F is around 35 light-years across.
2004-08-19💙 Add To Favorites
Why do many galaxies appear as spirals? A striking example is M101, shown above, whose relatively close distance of about 27 million light years allows it to be studied in some detail. Recent evidence indicates that a close gravitational interaction with a neighboring galaxy created waves of high mass and condensed gas which continue to orbit the galaxy center. These waves compress existing gas and cause star formation. One result is that M101, also called the Pinwheel Galaxy, has several extremely bright star-forming regions (called HII regions) spread across its spiral arms. M101 is so large that its immense gravity distorts smaller nearby galaxies.
2009-04-14 Adam Block, Mt. Lemmon SkyCenter, U. Arizona💙 Add To Favorites
Dark shapes with bright edges winging their way through dusty NGC 6188 are tens of light-years long. The emission nebula is found near the edge of an otherwise dark large molecular cloud in the southern constellation Ara, about 4,000 light-years away. Formed in that region only a few million years ago, the massive young stars of the embedded Ara OB1 association sculpt the fantastic shapes and power the nebular glow with stellar winds and intense ultraviolet radiation. The recent star formation itself was likely triggered by winds and supernova explosions, from previous generations of massive stars, that swept up and compressed the molecular gas. A false-color Hubble palette was used to create this sharp close-up image and shows emission from sulfur, hydrogen, and oxygen atoms in red, green, and blue hues. At the estimated distance of NGC 6188, the picture spans about 200 light-years.
2010-07-16 Piotrek Sadowski💙 Add To Favorites
From a geostationary orbit 36,000 kilometers above the equator, Russian meteorological satellite Elektro-L takes high-resolution images of our fair planet every 30 minutes. But only twice a year, during an Equinox, can it capture an image like this one, showing an entire hemisphere bathed in sunlight. At an Equinox, the Earth's axis of rotation is not tilted toward or away from the Sun, so the solar illumination can extend to both the planet's poles. Of course, this Elektro-L picture was recorded on September 22nd, at the northern hemisphere's autumnal equinox. For a moment on that date, the Sun was behind the geostationary satellite and a telltale glint of reflected sunlight is seen crossing the equator, at the location on the planet with satellite and sun directly overhead (5MB animated gif).
2013-09-28💙 Add To Favorites
When NASA's Voyager 2 spacecraft flew by distant Neptune in August of 1989, astronomers were shocked. Since Neptune receives only 3 percent the sunlight Jupiter does, they expected to find a dormant, dark, frigid planet. Instead, the Voyager images revealed evidence of a dynamic and turbulent world. One of the most spectacular discoveries was of the Great Dark Spot, shown here in close-up. Surprisingly, it was comparable in size and at the same relative southern latitude as Jupiter's Great Red Spot, appearing to be a similar rotating storm system. Winds near the spot were measured up to 1500 miles per hour, the strongest recorded on any planet. The Voyager data also revealed that the Great Dark Spot varied significantly in size during the brief flyby. When the Hubble Space Telescope viewed the planet in 1994, the spot had vanished -- only to be replaced by another dark spot in the planet's northern hemisphere!
1996-05-08💙 Add To Favorites