Messier 20 and 21

The beautiful Trifid Nebula, also known as Messier 20, is easy to find with a small telescope in the nebula rich constellation Sagittarius. About 5,000 light-years away, the colorful study in cosmic contrasts shares this well-composed, nearly 1 degree wide field with open star cluster Messier 21 (bottom right). Trisected by dust lanes the Trifid itself is about 40 light-years across and a mere 300,000 years old. That makes it one of the youngest star forming regions in our sky, with newborn and embryonic stars embedded in its natal dust and gas clouds. Estimates of the distance to open star cluster M21 are similar to M20’s, but though they share this gorgeous telescopic skyscape there is no apparent connection between the two. In fact, M21’s stars are much older, about 8 million years old. [via NASA] https://ift.tt/2BI0maN

Comet Heart and Soul

The greenish coma of comet 21P/Giacobini-Zinner stands out at the left of this telephoto skyscape spanning over 10 degrees toward the northern constellations Cassiopeia and Perseus. Captured on August 17, the periodic comet is the known parent body of the upcoming Draconid meteor shower. Predicted to be at its brightest next month, the comet is actually in the foreground of the rich starfield, only about 4 light-minutes from our fair planet. Giacobini-Zinner should remain too faint for your eye to see though, like the colorful Heart and Soul nebulae near the center of the sensitive digital camera’s field of view. But the pair of open star clusters at the right, h and Chi Persei, could just be seen by the unaided eye from dark locations. The Heart and Soul nebulae with their own embedded clusters of young stars a million or so years old, are each over 200 light-years across and 6 to 7 thousand light-years away. They are part of a large, active star forming complex sprawling along the Perseus spiral arm of our Milky Way Galaxy. Also known as the Double Cluster, h and Chi Persei are located at about that same distance. Periodic Giacobini-Zinner was visited by a spacecraft from Earth when the repurposed International Cometary Explorer passed through its tail in September 1985. [via NASA] https://ift.tt/2w5P7n1

Asteroid Ryugu from Hayabusa2

This big space diamond has an estimated value of over 80 billion dollars. It’s only diamond in shape, though — asteroid 162173 Ryugu is thought to be composed of mostly nickel and iron. Asteroids like Ryugu are interesting for several reasons, perhaps foremost because they are near the Earth and might, one day in the far future, pose an impact threat. In the nearer term, Ryugu is interesting because it may be possible to send future spacecraft there to mine it, thus providing humanity with a new source of valuable metals. Scientifically, Ryugu is interesting because it carries information about how our Solar System formed billions of years ago, and why its orbit takes it so close to Earth. Japan’s robotic spacecraft Hayabusa2 just arrived at this one-kilometer wide asteroid in late June. The featured image shows surface structures unknown before spacecraft Hayabusa2’s arrival, including rock fields and craters. Within the next three months, Hayabusa2 is scheduled to unleash several probes, some that will land on Ryugu and hop around, while Hayabusa2 itself will mine just a little bit of the asteroid for return to Earth. [via NASA] https://ift.tt/2OYUFaf

Active Prominences on a Quiet Sun

Why is the Sun so quiet? As the Sun enters into a period of time known as a Solar Minimum, it is, as expected, showing fewer sunspots and active regions than usual. The quietness is somewhat unsettling, though, as so far this year, most days show no sunspots at all. In contrast, from 2011 – 2015, during Solar Maximum, the Sun displayed spots just about every day. Maxima and minima occur on an 11-year cycle, with the last Solar Minimum being the most quiet in a century. Will this current Solar Minimum go even deeper? Even though the Sun’s activity affects the Earth and its surroundings, no one knows for sure what the Sun will do next, and the physics behind the processes remain an active topic of research. The featured image was taken three weeks ago and shows that our Sun is busy even on a quiet day. Prominences of hot plasma, some larger than the Earth, dance continually and are most easily visible over the edge. [via NASA] https://ift.tt/2wgX1cN

Asperitas Clouds Over New Zealand

What kind of clouds are these? Although their cause is presently unknown, such unusual atmospheric structures, as menacing as they might seem, do not appear to be harbingers of meteorological doom. Formally recognized as a distinct cloud type only last year, Asperitas clouds can be stunning in appearance, unusual in occurrence, and are relatively unstudied. Whereas most low cloud decks are flat bottomed, asperitas clouds appear to have significant vertical structure underneath. Speculation therefore holds that asperitas clouds might be related to lenticular clouds that form near mountains, or mammatus clouds associated with thunderstorms, or perhaps a foehn wind — a type of dry downward wind that flows off mountains. Such a wind called the Canterbury arch streams toward the east coast of New Zealand’s South Island. The featured image, taken above Hanmer Springs in Canterbury, New Zealand, in 2005, shows great detail partly because sunlight illuminates the undulating clouds from the side. [via NASA] https://ift.tt/2OMJ8ui

Tuiteando al vuelo, August 18, 2018 at 09:04PM

En Twitter encuentras odiadores infumables a los que no vale la pena nombrar y gente que da ejemplos hermosos de vida, como @manolocortesm https://t.co/5tpaI9fxRc

Tuiteando al vuelo, August 17, 2018 at 02:13PM

Plenamente de acuerdo. Trabajar en equipo, incluyendo todas las categorías profesionales, no sólo es beneficioso para el paciente, también mejora la calidad de vida de los profesionales, multiplica las sonrisas y favorece las sinergias. https://t.co/w71OAoIGXr

Perseid Fireball and Persistent Train

Before local midnight on August 12, this brilliant Perseid meteor flashed above the Poloniny Dark Sky Park, Slovakia, planet Earth. Streaking beside the summer Milky Way, its initial color is likely due to the shower meteor’s characteristically high speed. Moving at about 60 kilometers per second, Perseid meteors can excite green emission from oxygen atoms while passing through the thin atmosphere at high altitudes. Also characteristic of bright meteors, this Perseid left a lingering visible trail known as a persistent train, wafting in the upper atmosphere. Its development is followed in the inset frames, exposures separated by one minute and shown at the scale of the original image. Compared to the brief flash of the meteor, the wraith-like trail really is persistent. After an hour faint remnants of this one could still be traced, expanding to over 80 degrees on the sky. [via NASA] https://ift.tt/2Bkgnn6

Tuiteando al vuelo, August 16, 2018 at 07:56PM

El problema del joven del hospital de Manises es que revertir su situación de mala salud requiere mucho tiempo, mucha paciencia y mucho dinero. Si no le ayuda la Sanidad Pública, está condenado a muerte. https://t.co/06b80XFjsP vía @diariosur

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Tuiteando al vuelo, August 16, 2018 at 02:01PM

Nunca he escuchado una canción de Maluma completa, sería incluso incapaz de tararear alguna. Sólo creo que algún corte en redes sociales denunciando su tremendo machismo.

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