ASTRONOMY - Find the new moon

 2022 July 25

Find the New Moon
Image Credit & Copyright: Mohamad Soltanolkotabi

Explanation: Can you find the Moon? This usually simple task can be quite difficult. Even though the Moon is above your horizon half of the time, its phase can be anything from crescent to full. The featured image was taken in late May from Sant Martí d'Empúries, Spain, over the Mediterranean Sea in the early morning. One reason you can't find this moon is because it is very near to its new phase, when very little of the half illuminated by the Sun is visible to the Earth. Another reason is because this moon is near the horizon and so seen through a long path of Earth's atmosphere -- a path which dims the already faint crescent. Any crescent moon is only visible near the direction the Sun, and so only locatable near sunrise of sunset. The Moon runs through all of its phases in a month (moon-th), and this month the thinnest sliver of a crescent -- a new moon -- will occur in three days.

ASTRONOMY - Apollo 11 Landing Panorama

 2022 July 23

Apollo 11 Landing Panorama
Neil Armstrong, Apollo 11, NASA

Explanation: Have you seen a panorama from another world lately? Assembled from high-resolution scans of the original film frames, this one sweeps across the magnificent desolation of the Apollo 11 landing site on the Moon's Sea of Tranquility. The images were taken by Neil Armstrong looking out his window of the Eagle Lunar Module shortly after the July 20, 1969 landing. The frame at the far left (AS11-37-5449) is the first picture taken by a person on another world. Toward the south, thruster nozzles can be seen in the foreground on the left, while at the right, the shadow of the Eagle is visible to the west. For scale, the large, shallow crater on the right has a diameter of about 12 meters. Frames taken from the Lunar Module windows about an hour and a half after landing, before walking on the lunar surface, were intended to initially document the landing site in case an early departure was necessary.

ASTRONOMY - Messier 10 and Comet

 2022 July 21

Messier 10 and Comet
Image Credit & Copyright: German Penelas Perez

Explanation: Imaged on July 15 2022, comet C/2017 K2 (PanSTARRS) had a Messier moment, sharing this wide telescopic field of view with globular star cluster Messier 10. Of course M10 was cataloged by 18th century comet hunter Charles Messier as the 10th object on his list of things that were definitely not comets. While M10 is about 14 thousand light-years distant, this comet PanSTARRS was about 15 light-minutes from our fair planet following its July 14 closest approach. Its greenish coma and dust tail entertaining 21st century comet watchers, C/2017 K2 is expected to remain a fine telescopic comet in northern summer skies. On a maiden voyage from our Solar System's remote Oort Cloud this comet PanSTARRS was discovered in May 2017 when it was beyond the orbit of Saturn. At the time that made it the most distant active inbound comet known. Its closest approach to the Sun will be within 1.8 astronomical units on December 19, beyond the orbital distance of Mars.

ASTRONOMY - Pleiades over Half Dome

 2022 July 19

Pleiades over Half Dome
Image Credit & Copyright: Dheera Venkatraman

Explanation: Stars come in bunches. The most famous bunch of stars on the sky is the Pleiades, a bright cluster that can be easily seen with the unaided eye. The Pleiades lies only about 450 light years away, formed about 100 million years ago, and will likely last about another 250 million years. Our Sun was likely born in a star cluster, but now, being about 4.5 billion years old, its stellar birth companions have long since dispersed. The Pleiades star cluster is pictured over Half Dome, a famous rock structure in Yosemite National Park in California, USA. The featured image is a composite of 28 foreground exposures and 174 images of the stellar background, all taken from the same location and by the same camera on the same night in October 2019. After calculating the timing of a future juxtaposition of the Pleiades and Half Dome, the astrophotrographer was unexpectedly rewarded by an electrical blackout, making the background sky unusually dark.

ASTRONOMIA - Sabe como soa um buraco negro no espaço? Assim

LE SON D'UN TROU NOIR (VOIR LINK)

Agora já pode conhecer um pouco mais do que se passa no Espaço: a NASA divulgou um áudio de 35 segundos que replica os sons que se ouvem dentro de um buraco negro.

O som é uma combinação de dados eletromagnéticos recolhidos do Perseus Galaxy Cluster – um aglomerado de galáxias na constelação de Perseu -, que fica a cerca de 240 milhões de anos-luz de distância.

A NASA, desde há dois anos, decidiu começar a traduzir as representações visuais do Espaço em algo que pudesse ser apreciado ao ouvido.

“Comecei os primeiros 10 anos da minha carreira a prestar uma maior atenção apenas ao visual, e percebi que havia uma falha para pessoas que não eram aprendizes visuais ou para pessoas cegas ou com pouca visão”, explicou a cientista visual Kimberly Arcand à NPR.

Em 2003, os astrónomos descobriram que as ondas emitidas pelo buraco negro causavam ondulações no gás quente do aglomerado, podendo, assim, traduzi-las para uma nota musical. A verdade é que nem sempre os buracos negros soam da mesma forma, dependendo da sua posição no centro das galáxias.

Um buraco negro é uma região com uma força da gravidade tão intensa, que atrai tudo à sua volta, inclusive a própria luz.

Visão

ASTRONOMY - Stephan's Quintet from Webb, Hubble, and Subaru

 2022 July 18

Stephan's Quintet from Webb, Hubble, and Subaru
Image Credit: Webb, Hubble, Subaru; NASA, ESA, CSA, NOAJ, STScI; Processing & Copyright: Robert Gendler

Explanation: OK, but why can't you combine images from Webb and Hubble? You can, and today's featured image shows one impressive result. Although the recently launched James Webb Space Telescope (Webb) has a larger mirror than Hubble, it specializes in infrared light and can't see blue -- only up to about orange. Conversely, the Hubble Space Telescope (Hubble) has a smaller mirror than Webb and can't see as far into the infrared as Webb, but can image not only blue light but even ultraviolet. Therefore, Webb and Hubble data can be combined to create images across a wider variety of colors. The featured image of four galaxies from Stephan's Quintet shows Webb images as red and also includes images taken by Japan's ground-based Subaru telescope in Hawaii. Because image data for Webb, Hubble, and Subaru are made freely available, anyone around the world can process it themselves, and even create intriguing and scientifically useful multi-observatory montages.

ASTRONOMY - Europa and Jupiter from Voyager 1

 2022 July 17

Europa and Jupiter from Voyager 1
Image Credit: NASA, Voyager 1, JPL, Caltech; Processing & License: Alexis Tranchandon / Solaris

Explanation: What are those spots on Jupiter? Largest and furthest, just right of center, is the Great Red Spot -- a huge storm system that has been raging on Jupiter possibly since Giovanni Cassini's likely notation of it 357 years ago. It is not yet known why this Great Spot is red. The spot toward the lower left is one of Jupiter's largest moons: Europa. Images from Voyager in 1979 bolster the modern hypothesis that Europa has an underground ocean and is therefore a good place to look for extraterrestrial life. But what about the dark spot on the upper right? That is a shadow of another of Jupiter's large moons: Io. Voyager 1 discovered Io to be so volcanic that no impact craters could be found. Sixteen frames from Voyager 1's flyby of Jupiter in 1979 were recently reprocessed and merged to create the featured image. Forty-five years ago this August, Voyager 1 launched from Earth and started one of the greatest explorations of the Solar System ever.

ASTRONOMY - Tycho and Clavius at Dawn

 2022 July 16

Tycho and Clavius at Dawn
Image Credit & Copyright: Eduardo Schaberger Poupeau

Explanation: South is up in this dramatic telescopic view of the lunar terminator and the Moon's rugged southern highlands. The lunar landscape was captured on July 7 with the moon at its first quarter phase. The Sun shines at a low angle from the right as dawn comes to the region's young and old craters Tycho and Clavius. About 100 million years young, Tycho is the sharp-walled 85 kilometer diameter crater below and left of center. Its 2 kilometer tall central peak and far crater wall reflect bright sunlight, Its smooth floor lies in dark shadow. Debris ejected during the impact that created Tycho make it the stand out lunar crater when the Moon is near full though. They produce a highly visible radiating system of light streaks or rays that extend across much of the lunar near side. In fact, some of the material collected at the Apollo 17 landing site, about 2,000 kilometers away, likely originated from the Tycho impact. One of the oldest and largest craters on the Moon's near side, 225 kilometer diameter Clavius is due south (above) of Tycho. Clavius crater's own ray system resulting from its original impact event would have faded long ago. The old crater's worn walls and smooth floor are now overlayed by newer smaller craters from impacts that occurred after Clavius was formed. Reaching above the older crater, tops of the newer crater walls reflect this dawn's early light to create narrow shining arcs within a shadowed Clavius.

ASTRONOMY - Lubovna Full Moon

 2022 July 15

Lubovna Full Moon
Petr Horalek / Institute of Physics in Opava

Explanation: On July 13 this well-planned telephoto view recorded a Full Moon rising over Lubovna Castle in eastern Slovakia. The photographer was about 3 kilometers from the castle walls and about 357,000 kilometers from this Full Moon near perigee, the closest point in its elliptical orbit. Known to some as supermoons, full moons near perigee are a little brighter and larger in planet Earth's sky when compared to full moons that occur near the average lunar distance of around 384,000 kilometers. Of course any Full Moon near the horizon can show the effects of refraction over a long sight-line through dense clear atmosphere. In this image, atmospheric refraction creates the slight green flash framed by thin clouds near the top, with a ragged red rim along the bottom edge of July's perigee Full Moon.

ASTRONOMY - Webb's Southern Ring Nebula

 2022 July 14

Webb's Southern Ring Nebula
Image Credit: NASA, ESA, CSA, STScI, NIRCam

Explanation: Cataloged as NGC 3132 the Southern Ring Nebula is a planetary nebula, the death shroud of a dying sun-like star some 2,500 light-years from Earth. Composed of gas and dust the stunning cosmic landscape is nearly half a light-year in diameter, explored in unprecedented detail by the James Webb Space Telescope. In this NIRCam image the bright star near center is a companion of the dying star. In mutual orbit, the star whose transformation has ejected the nebula's gas and dust shells over thousands of years is the fainter stellar partner. Evolving to become a white dwarf, the faint star appears along the diffraction spike extending toward the 8 o'clock position. This stellar pair's orbital motion has resulted the complex structures within the Southern Ring Nebula.