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NASA Astronomy Picture of the Day:

What if you could see X-rays? The night sky would seem a strange and unfamiliar place. X-rays are about 1,000 times more energetic than visible light photons and are produced by violent explosions and high temperature astronomical environments. Instead of the familiar steady stars, the sky would seem to be filled with exotic stars, active galaxies, and hot supernova remnants. The featured X-ray image captures in unprecedented detail the entire sky in X-rays as seen by the eROSITA telescope onboard Spektr-RG satellite, orbiting around the L2 point of the Sun-Earth system, launched last year. The image shows the plane of our Milky Way galaxy across the center, a diffuse and pervasive X-ray background, the hot interstellar bubble known as the North Polar Spur, sizzling supernova remnants such as Vela, the Cygnus Loop and Cas A, energetic binary stars including Cyg X-1 and Cyg X-2, the LMC galaxy, and the Coma, Virgo, and Fornax clusters of galaxies. This first sky scan by eROSITA located over one million X-ray sources, some of which are not understood and will surely be topics for future research.

Photo by TeamMPEIKI

NASA Astronomy Picture of the Day:

What are those dark streaks in this composite image of yesterday's solar eclipse? They are reversed shadows of mountains at the edge of the Moon. The center image, captured from Xiamen, China, has the Moon's center directly in front of the Sun's center. The Moon, though, was too far from the Earth to completely block the entire Sun. Light that streamed around all of the edges of the Moon is called a ring of fire. Images at each end of the sequence show sunlight that streamed through lunar valleys. As the Moon moved further in front of the Sun, left to right, only the higher peaks on the Moon's perimeter could block sunlight. Therefore, the dark streaks are projected, distorted, reversed, and magnified shadows of mountains at the Moon's edge. Bright areas are called Bailey's Beads. Only a narrow swath across Earth's Eastern Hemisphere was able to see yesterday's full annular solar eclipse. Next June, though, a narrow swath across Earth's Northern Hemisphere will be able to see the next annular solar eclipse. A total solar eclipse will be visible at the bottom of the world near the end of this year. Gallery: Notable images of the Annular Solar Eclipse of 2020 June submitted to APOD

Photo by Wang LetianEyes at Night

© TashiTobgyal/ @IndianExpress 

NASA Astronomy Picture of the Day:

It may look like Earthrise, but it's actually Venus-set. Just after sunrise two days ago, both the Moon and Venus also rose. But then the Moon overtook Venus. In the featured image sequence centered on the Moon, Venus is shown increasingly angularly close to the Moon. In the famous Earthrise image taken just over 50 years ago, the Earth was captured rising over the edge of the Moon, as seen from the Apollo 8 crew orbiting the Moon. This similar Venus-set image was taken from Earth, of course, specifically Estonia. Venus shows only a thin crescent because last week it passed nearly in front of the Sun, as seen from Earth. The Moon shows only a thin crescent because it will soon be passing directly in front of the Sun, as seen from Earth. Today, in fact, two days after this image was taken, the Moon will create a solar eclipse, with a thin swath across the Earth treated to an annular solar eclipse. Gallery: Notable images of the Venus - Mooon conjunction of 2020 June submitted to APOD

Photo by Dzmitry Kananovich

NASA Astronomy Picture of the Day:

Today's solstice brings summer to planet Earth's northern hemisphere. But the northern summer solstice arrived for ringed planet Saturn over three years ago on May 24, 2017. Orbiting the gas giant, Saturn's moon Titan experiences the Saturnian seasons that are about 7 Earth-years long. Larger than inner planet Mercury, Titan was captured in this Cassini spacecraft image about two weeks after its northern summer began. The near-infrared view finds bright methane clouds drifting through Titan's dense, hazy atmosphere as seen from a distance of about 507,000 kilometers. Below the clouds, dark hydrocarbon lakes sprawl near its fully illuminated north pole.

NASA Astronomy Picture of the Day:

Transfusing sunlight through a darkened sky, this beautiful display of noctilucent clouds was captured earlier this week, reflected in calm waters from Nykobing Mors, Denmark. From the edge of space, about 80 kilometers above Earth's surface, the icy clouds themselves still reflect sunlight, though the Sun is below the horizon as seen from the ground. Usually spotted at high latitudes in summer months the night shining clouds have made an early appearance this year as northern nights grow short. Also known as polar mesopheric clouds they are understood to form as water vapor driven into the cold upper atmosphere condenses on the fine dust particles supplied by disintegrating meteors or volcanic ash. NASA's AIM mission provides daily projections of noctilucent clouds as seen from space.

Photo by Ruslan Merzlyakov

NASA Astronomy Picture of the Day:

This telescopic close-up shows off the central regions of otherwise faint emission nebula IC 410, captured under backyard suburban skies with narrowband filters. It also features two remarkable inhabitants of the cosmic pond of gas and dust. Below and right of center are the tadpoles of IC 410. Partly obscured by foreground dust, the nebula itself surrounds NGC 1893, a young galactic cluster of stars. Formed in the interstellar cloud a mere 4 million years ago, the intensely hot, bright cluster stars energize the glowing gas. Composed of denser cooler gas and dust, the tadpoles are around 10 light-years long and are likely sites of ongoing star formation. Sculpted by stellar winds and radiation their heads are outlined by bright ridges of ionized gas while their tails trail away from the cluster's central young stars. IC 410 lies some 10,000 light-years away, toward the nebula-rich constellation Auriga.

Photo by Trevor Jones

NASA Astronomy Picture of the Day:

What role do magnetic fields play in interstellar physics? Analyses of observations by ESA's Planck satellite of emission by small magnetically-aligned dust grains reveal previously unknown magnetic field structures in our Milky Way Galaxy -- as shown by the curvy lines in the featured full-sky image. The dark red shows the plane of the Milky Way, where the concentration of dust is the highest. The huge arches above the plane are likely remnants of past explosive events from our Galaxy's core, conceptually similar to magnetic loop-like structures seen in our Sun's atmosphere. The curvy streamlines align with interstellar filaments of neutral hydrogen gas and provide tantalizing evidence that magnetic fields may supplement gravity in not only in shaping the interstellar medium, but in forming stars. How magnetism affected our Galaxy's evolution will likely remain a topic of research for years to come.

NASA Astronomy Picture of the Day:

Welcome to the quadranscentennial year of the Astronomy Picture of the Day. Perhaps a source of consistency for some, APOD is still here. To help celebrate APOD's Silver Anniversary, some of APOD's TVAoTaSMD have recorded a birthday greeting and thanks to APOD's readership in today's featured video. Many have also highlighted a few of their favorite APOD images. In collaboration with NASA through APOD, these and other volunteers help to inform the world, in most major world languages and over most major media platforms, of NASA and humanity's growing knowledge, active exploration, and inspiring visualizations of the amazing astronomical universe in which we live. APOD's founders (still alive!) would also like to offer a sincere thank you -- not only to our TVAoTaSMD -- but to APOD's readership for continued interest, support, and many gracious communications over the years.

NASA Astronomy Picture of the Day:

What's rising above the horizon behind those clouds? It's the Sun. Most sunrises don't look like this, though, because most sunrises don't include the Moon. In the early morning of 2013 May 10, however, from Western Australia, the Moon was between the Earth and the rising Sun. At times, it would be hard for the uninformed to understand what was happening. In an annular eclipse, the Moon is too far from the Earth to block the entire Sun, and at most leaves a ring of fire where sunlight pours out around every edge of the Moon. The featured time-lapse video also recorded the eclipse through the high refraction of the Earth's atmosphere just above the horizon, making the unusual rising Sun and Moon appear also flattened. As the video continues on, the Sun continues to rise, and the Sun and Moon begin to separate. This weekend, a new annular solar eclipse will occur, visible from central Africa, the Arabian Peninsula, and a narrow band across Asia, with much of Earth's Eastern hemisphere being able to see a partial solar eclipse.

NASA Astronomy Picture of the Day:

What are these humans doing? Dancing. Many humans on Earth exhibit periods of happiness, and one method of displaying happiness is dancing. Happiness and dancing transcend national boundaries and occur in practically every human society. Above, Matt Harding traveled through many nations on Earth, planned on dancing, and filmed the result. The featured video, one in a series of similar videos, is perhaps a dramatic example that humans from all over planet Earth feel a common bond as part of a single species. Happiness is frequently contagious -- few people are able to watch the featured video without smiling. APOD across world languages: Arabic, Catalan, Chinese (Beijing), Chinese (Taiwan), Croatian, Czech, Dutch, Farsi, French, French, German, Hebrew, Indonesian, Japanese, Korean, Montenegrin, Polish, Russian, Serbian, Slovenian, Spanish and Ukrainian

NASA Astronomy Picture of the Day:

Clouds are white but the sky is dark in this snapshot of Launch Complex 39A at the Kennedy Space Center. The dramatic daytime sky is partly due to the black and white photo captured with a digital camera at near-infrared wavelengths. Taken at 3:22 p.m. EDT Saturday May 30 the launch was pretty dramatic too as a Falcon 9 rocket lofted a Crew Dragon spacecrat towards low-Earth orbit. Astronauts Robert Behnken and Douglas Hurley were onboard, the first crew launched from a United States spaceport since the conclusion of the Space Shuttle Program in 2011. A few minutes after launch, the Falcon 9 first stage returned to land on Of Course I Still Love You (that's an autonomous spaceport drone ship ...) patiently waiting off the Florida coast. The two astronauts guided their craft to a successfull docking with the International Space Station’s Harmony module at 10:16 a.m. EDT Sunday May 31.