Etiqueta: NASA

Do you recognize the constellation of Orion? It may be harder than usual in today’s featured image because the camera has zoomed in on the center, and the exposure is long enough to enhance nebulas beyond what the unaided human eye can see. Still, once you become oriented, you can see Orion’s three belt stars lined up vertically near the image center, and even locate the familiar Orion Nebula on the upper left. Famous faint features that are also visible include the dark Horsehead Nebula indentation near the image center, and the dusty Flame Nebula just to its right. Part of the Orion-encircling Barnard’s Loop can also be found on the far right. The image combines multiple sky-tracking shots of the background in different colors with a single static foreground exposure taken at twilight — all captured with the same camera and from the same location. The picturesque scene was captured early last year from mountains in San Juan, Argentina. [via NASA] https://ift.tt/2MIQOPe

Why is Venus surrounded by a bright ring? Sometimes called a ring of fire, this rare ring is caused by the Sun’s light being visible all around an object. Usually seen around the Moon during an annular solar eclipse, the ring of fire is also visible when either Venus or Mercury cross the face of our Sun. In the featured pictured taken last week, though, Venus did not pass directly in front of the Sun — the complete atmospheric ring was caused by sunlight refracting through Venus’ thick atmosphere. Venus passed within one degree of the Sun during its inferior conjunction, as it moved from the evening to the morning sky.  The extreme brightness of the nearby Sun made capturing such an image very difficult — the featured image was only made possible by using a temporary filter to block direct sunlight. The image was captured from Thorton, Leicestershire, UK. The pervasive blue sky glow indicates that the image was actually captured during the day. [via NASA] https://ift.tt/3cFpGLO

The Cat’s Eye Nebula (NGC 6543) is one of the best known planetary nebulae in the sky. Its haunting symmetries are seen in the very central region of this stunning false-color picture, processed to reveal the enormous but extremely faint halo of gaseous material, over three light-years across, which surrounds the brighter, familiar planetary nebula. Made with data from the Nordic Optical Telescope in the Canary Islands, the composite picture shows extended emission from the nebula. Planetary nebulae have long been appreciated as a final phase in the life of a Sun-like star. Only much more recently however, have some planetaries been found to have halos like this one, likely formed of material shrugged off during earlier active episodes in the star’s evolution. While the planetary nebula phase is thought to last for around 10,000 years, astronomers estimate the age of the outer filamentary portions of this halo to be 50,000 to 90,000 years. [via NASA] https://ift.tt/2A8S0Jb

Comet PanSTARRs, C/2017 T2, shared this stunning telescopic field of view with galaxies M81 and M82 on May 22/23. Of course, the galaxies were some 12 million light-years distant and the comet about 14 light-minutes away, seen in planet Earth’s sky toward the Big Dipper. A new visitor from the Oort Cloud, this Comet PanSTARRs was discovered in 2017 by the PanSTARRs survey telescope when the comet was over 1 light-hour from the Sun, almost as distant as the orbit of Saturn. With a beautiful coma and dust tail, this comet has been a solid northern hemisphere performer for telescope wielding comet watchers this May, following its closest approach to the Sun on May 4. In this deep image from dark California skies the outbound comet even seems to develop a short anti-tail as it leaves the inner Solar System. [via NASA] https://ift.tt/2UfW3dy

Still bathed in sunlight the International Space Station (ISS) arced through this Manhattan evening sky on May 30. Moving left to right, its bright trail was captured in this composite image with a series of 5 second long exposures. Stars left short trails and lights were reflected in still waters looking toward the north across the Central Park reservoir. Chasing the ISS in low Earth orbit the Crew Dragon spacecraft dubbed Endeavour also left a trail through that urban night. Seen about 6 hours after its launch the spacecraft’s faint trail appears above the ISS, shown in the inset just as the two approached the bank of clouds at the right. Dragon Endeavour docked successfully with the ISS about nineteen hours after reaching orbit. [via NASA] https://ift.tt/2BxBbrD

Sharp telescopic views of NGC 3628 show a puffy galactic disk divided by dark dust lanes. Of course, this deep portrait of the magnificent, edge-on spiral galaxy puts some astronomers in mind of its popular moniker, the Hamburger Galaxy. It also reveals a small galaxy nearby, likely a satellite of NGC 3628, and a faint but extensive tidal tail. The drawn out tail stretches for about 300,000 light-years, even beyond the right edge of the wide frame. NGC 3628 shares its neighborhood in the local universe with two other large spirals M65 and M66 in a grouping otherwise known as the Leo Triplet. Gravitational interactions with its cosmic neighbors are likely responsible for creating the tidal tail, as well as the extended flare and warp of this spiral’s disk. The tantalizing island universe itself is about 100,000 light-years across and 35 million light-years away in the northern springtime constellation Leo. [via NASA] https://ift.tt/2XtqsXR

Every time Venus passes the Earth, it shows the same face. This remarkable fact has been known for only about 50 years, ever since radio telescopes have been able to peer beneath Venus’ thick clouds and track its slowly rotating surface. This inferior conjunction — when Venus and Earth are the closest — occurs today. The featured animation shows the positions of the Sun, Venus and Earth between 2010-2023 based on NASA-downloaded data, while a mock yellow ‘arm’ has been fixed to the ground on Venus to indicate rotation. The reason for this unusual 1.6-year resonance is the gravitational influence that Earth has on Venus, which surprisingly dominates the Sun’s tidal effect. If Venus could be seen through the Sun’s glare today, it would show just a very slight sliver of a crescent. Although previously visible in the evening sky, starting tomorrow, Venus will appear in the morning sky — on the other side of the Sun as viewed from Earth. [via NASA] https://ift.tt/2z2bWwS

Humanity is under attack. The attack is not from large tentacle-flailing aliens, but from invaders so small they can barely be seen, and so strange they are not even clearly alive. All over planet Earth, the human home world, DNA-based humans are being invaded by the RNA-based SARS-CoV2. The virus, which creates a disease known as COVID-19, specializes in reprogramming human cells into zombies that manufacture and release copies of itself. Pictured here is a high magnification image of a human cell covered by attacking novel coronavirus SARS-CoV2 (orange). Epic battles where two species square off in a fight to the death are not unusual on Earth, with several just involving humans typically ongoing at any time. Even so, most humans are predicted to survive. After several years, humanity expects to win this war — but only after millions of humans have died and trillions of coronaviruses have been destroyed. [via NASA] https://ift.tt/2zVaAo3

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, Hershel 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 15 light years, features two colors detected 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. [via NASA] https://ift.tt/3dl9Zup

It was bright and green and stretched across the sky. This striking aurora display was captured in 2016 just outside of Östersund, Sweden. Six photographic fields were merged to create the featured panorama spanning almost 180 degrees. Particularly striking aspects of this aurora include its sweeping arc-like shape and its stark definition. Lake Storsjön is seen in the foreground, while several familiar constellations and the star Polaris are visible through the aurora, far in the background. Coincidently, the aurora appears to avoid the Moon visible on the lower left. The aurora appeared a day after a large hole opened in the Sun’s corona allowing particularly energetic particles to flow out into the Solar System. The green color of the aurora is caused by oxygen atoms recombining with ambient electrons high in the Earth’s atmosphere. [via NASA] https://ift.tt/2TTTA8t