Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.



  • Content Count

  • Joined

  • Last visited

  • Days Won


astroavani last won the day on January 14

astroavani had the most liked content!

Community Reputation

6,826 Excellent

About astroavani

  • Rank
    Sub Dwarf

Profile Information

  • Gender
  • Interests
  • Location
    Canoas, Brazil
  1. Não, apenas mudei um pouco, é autor desconhecido!
  2. TALKING TO THE MOON On a starry night She appears quietly Its brightness gets stronger Clearing my path The sky is more beautiful With the reflection of your gaze And in the silence of the night She makes me walk As far as she is Will never fail to shine Your light doesn't go out And let life take me Whether new or full moon I will always be your admirer Your beauty fascinates me In awe of the creator
  3. Domes of Arago This is the best week for lunar observation, the shadows are long and the formations stand out easily. In this particular photo we can see the domes near Arago. There are a pair of very large domes, one to the north (Arago Alpha) and one to the west (Arago Beta). These are two of the largest and most prominent domes of the Moon and, halfway between Arago a and the Maclear crater (160 kilometers to the northeast), you will find a challenging group of four smaller domes. It will be a good victory for you, if you can identify them. The domes or domes, are low and rounded structures, found in areas of mares where formerly the growing magma pushed upwards and caused the lunar surface to jump in bubble-like bumps. Sometimes, the underlying pressure was not enough to cause the magma to break; others, the domes erupted in small, slightly inclined shield volcanoes, and their holes in the summit can actually be seen under low angle lighting as seen here: https://www.astrobin.com/200363/?nc=user The lunar domes do not attract attention, like the most spectacular craters and mountains, so they are easily ignored, but they are fascinating objects and are worth the effort to look for. As the endogenous theory of crater formation has been widely contested, it is fun to hunt for evidence that there was indeed volcanic activity on the Moon. You will need at least 15 cm of aperture and 150 to 300X power to view most of the domes. As the lunar progresses, pay attention to the region near the terminator, it is a good challenge to try to identify these formations in addition to being a testament to the good optical quality of your equipment. Source: Andrew Planck Adaptation: Avani Soares
  4. The Seeliger effect Generally, when you look at Saturn through a telescope before or after opposition, the rings look as bright as the planet's globe. For days at the time of the opposition, however, the rings suddenly intensify in apparent brightness, blinding the globe before returning to its normal appearance. German astronomer Hugo von Seeliger (1849-1924) noticed this change for the first time in 1887. Because of his pioneering research on its cause, which led him to conclude that Saturn's rings were composed of small particles, the effect was named in honor of that scientist. Two main physical processes lead to the Seeliger effect: shadow hiding and coherent backscattering. When we see Saturn directly illuminated by the Sun (as it is during opposition), the planet's shadow “hides” behind the globe, putting more surface of the ring in view. As a result, the rings appear to lighten. The same angle of direct illumination also causes the shadows of individual particles in the rings to temporarily disappear, improving the result. The Seeliger effect, which combined the enhancements of shadow hiding and coherent backscatter, makes Saturn's rings appear brighter the closer the planet is to the opposite side of the sun. The Seeliger effect, which combines the enhancements of shadow hiding and coherent backscatter, makes Saturn's rings appear brighter the closer the planet is to the side opposite the Sun, as in the top image compared to the bottom. Christopher Go But that is not all. Observations of the effect of the opposition on the Cassini spacecraft's Saturn rings, in orbit around the planet, reveal that "coherent backscattering" also contributes significantly to the phenomenon. This occurs when sunlight interacts with the collective particles in the planet's rings; the reflections of many irregular pieces of rock and dust combine to produce a single, more coherent (coherent) light. This light spreads back to our eyes and makes the rings appear lighter. In contrast, and in the days immediately following, we see the combination of these two mechanisms as a temporary increase in the overall illumination of the rings. The only way to fully appreciate the effect visually, however, is to monitor the planet and its rings during the days around that magical moment - weather permitting. Source: Astronomy; Stephen James O'Meara
  5. A Cave in Marius HillsMost researchers agree that the Moon is about 4.5 billion years old, possibly about 50 million years younger than the rest of the solar system. One of the theories says that the moon was formed when another planet (about the size of Mars) struck the molten stone ball that was Earth at that time. Some of the remains of that collision were turned into space where they eventually reformulated as a solid mass - our current moon.Although this part of the Moon's history is generally accepted, other areas are still very uncertain. One is the question of when there was volcanic activity on the Moon, how long this activity lasted and how much there was. Early studies of lunar volcanic rocks were possible when samples were brought to Earth by astronauts during the Apollo missions from 1969 to 1972.Studies suggest that volcanic activity on the moon began soon after the formation of the moon, or about 0.5 billion years earlier than previously thought. Most of the volcanism on the Moon probably happened around 3.8 to 3.9 billion years ago, and mostly stopped about 3 billion years ago.In December 2009, the Kaguya spacecraft sent images of a large hole in a winding wave in the Marius Hills region, a volcanic area on the lunar side. Sinuous rails are formed in two different ways: as open lava canals and / or as lava tubes, many of which subsequently collapse. Because the Marius Hills well is in the middle of a winding rille, it probably represents a collapse in the roof of a lava tube. The well itself may have been caused by a meteorite impact that pierced through the roof of the lava tube.The Marius Hills well was discovered in images from the Japanese camera SELENE / Kaguya Terrain and Multiband Imager, and reported in Geophysical Research Letters. The Japanese team, led by Junichi Haruyama, performed multiple observations of the well using both the Terrain Camera and the Multiband Imager at resolutions up to 6 meters / pixel (see central photos). The LROC image (shown here at the top left) at 0.5 meters / pixel is the highest resolution image of the Marius Hills batch to date! The SELENE / Kaguya Terrain Camera team also made a film about the hole (https://www.lpi.usra.edu/lunar/lunar_flyovers/marius_hills/). The Marius Hills region was volcanically quite active in the past and contains numerous volcanic features including winding riles like those labeled Rilles A and B plus numerous hills that are actually domes and can be seen quite clearly in my photo.How and when did the well caves form? On Earth, volcanic pit craters are formed as the roof of a lava tube collapses, often while the magma is still flowing underground. The resulting aperture is often referred to as a skylight. Can we determine if the moon skylights formed during or after the lavas on the floor flow? Perhaps the best place to start looking for evidence is on the pit floor. If the skylight was formed long after the eruptions had ceased and the underground lava tubes were cold, you might find a chaotic pile of rubble on the floor. If the well collapsed into an active lava tube, you can find the smooth, frozen surface of the last lava that flowed through the tube.This well or skylight is intriguing because it suggests that many other lunar Rilles may also have wells or skylights formed through the collapse of the lava tube.Robert Zimmerman in this article; http://behindtheblack.com/behind-the-black/essays-and-commentaries/single-rope-techinque-on-the-moon/, makes some interesting assumptions about the depth of the well and the difficulty in exploring it in future missions.Lava tubes may be useful as sites for lunar bases (see a report by Fred Hörz of JSC here:http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1985lbsa.conf..405H&data_type=PDF_HIGH&whole_paper=YES&type=PRINTER&filetype=.pdf. The interior of lava tubes could protect human explorers from different aspects of the lunar environment, including cosmic rays, meteorite impacts, and extreme temperature differences between lunar day and night. Like caves on Earth, lunar caves, including lava tubes, have temperatures that are constant. Our human ancestors, who in a distant age inhabited caves to protect themselves at the dawn of civilization, will have known, their descendants doing the same in that silver star that illuminated the shadows and turned away the darkness and their deepest fears!Sources: KaKuya / Jaxa-Selene - LROC / NASA - Behind the Black / Robert Zimmerman - Lunar and Planetary Institute - Lava Tube / Friedrich HörzAdaptation and text: Avani Soares
  6. So create courage and get to work!
  7. I'm not entirely sure, but something around 1000X magnification. A correct calculation could be made, but I am making a rough estimate.
  8. LOL, amazed because you liked it?
  9. I had the opportunity to borrow a monochrome camera to do the tests I always wanted on the Moon.Below are the first results for colleagues to analyze.I realized from the outset the advantage of mono cameras for specific wavelengths since I normally use an ASI290MC to do all my captures. This is mainly explained by the fact that, without the layer matrix, a monochrome camera uses 100% of its pixels to perform the capture, while a color camera would use only 25% to capture on the IR 685 which was the filter used.Despite everything, due to the great fluctuation of my seeing, varying in a matter of a few minutes, I do not discard the advantages of a color camera for color captures, since while a mono camera would make only 1 film I can make at least about 4 with the colored one. This greatly increases the chance of catching a brief favorable moment that can save an entire section of photography.Moon on May 4, 2020.C14 Edge + ASI 178MM + IR pass 685Total of 2000 frames per photo with 350 stacking.
  10. The planet Saturn is being recognized as the "moon king" of our solar system. Jupiter used to keep track of most of the moons that orbit around it. It has 79. But scientists in the United States have announced the discovery of 20 new moons around Saturn. This gives the planet a new total of 82 moons. The researchers made the discovery using the powerful Subaru telescope in Hawaii. They collected information over a period of several years. The team also used new computer models to identify moons and track activities in orbit. The discovery was announced in late September 2019 by the International Astronomical Union's Minor Planet Center. The center is responsible for identifying all the smallest planets in the world, comets and "natural outer satellites". The organization also measures the orbital movements of such objects. Researchers say the newly found moons are very small, measuring about five kilometers in diameter. The team has managed to discover them now because of the best technology that has become available in recent years. This includes more powerful telescopes and greater computing power. One of the newly identified moons orbits Saturn at a great distance, some 25 million kilometers from the planet. This is further away than any other moon on Saturn. Seventeen of the new moons orbit Saturn backwards. In other words, its movement is opposite to the rotation of the planet. The other three orbit in the same direction as the planet rotates. The researchers said that several moons appear to have been formed from parts of larger moons. These past moons probably split up into collisions with other moons or comets or asteroids. "These new moons show us that the solar system was a very chaotic place in the distant past, with objects flying all over the place," these moons are among the last remaining evidence of the formation of the solar system. All other objects were either pushed out or became parts of other planets.
  11. Researchers from Canada have used computer models to show that our Solar System could have had an extra gas giant planet in the mix around 4 billion years ago – until Jupiter booted it out, that is. The idea that there were originally five gas giants – in addition to Jupiter, Saturn, Uranus, and Neptune – was first proposed back in 2011, to help explain why the Solar System currently looks the way it does. As it turns out, the orbit of Mars and Earth don't really make sense if there were only ever the planets we have today. But researchers haven't been able to explain until now what could have happened to that extra planet, with both Jupiter and Saturn named as potential culprits for doing the kicking out. "Our evidence points to Jupiter," said lead researcher Ryan Cloutier from the University of Toronto, who describes the whole thing as an "interplanetary chess game". The mystery lost planet in question is believed to have had the mass of an ice giant, which means that it was heavier than Saturn and Jupiter, and in the same class as Neptune and Uranus. So how exactly does a lighter planet suddenly kick an ice giant clear out of the Solar System? Planetary ejections generally happen as a result of a close planetary encounter - but not necessary a collision - which causes one of the objects to accelerate so rapidly that it's able to break free from the massive gravitational pull of the Sun and go slingshotting out into the galaxy, becoming what's known as a rogue planet. In this case, the ejection could be the result of Jupiter moving closer to the Sun from further out in the Solar System, affecting the orbit of other planets on its way. Earlier studies had struggled to work out exactly which of the remaining planets could have done this, but in the new research, the astronomers from the University of Toronto realised that up until now, no one had factored in the effect this encounter would have had on the moons orbiting the giant planets. So the team decided to look at the trajectories of Callisto and Iapetus – two of the regular moons orbiting Jupiter and Saturn respectively. Using computer models, they investigated the likelihood of the moons having the same orbit as they do today if they'd been involved in a mass planetary ejection 4 billion years ago. "Ultimately, we found that Jupiter is capable of ejecting the fifth giant planet while retaining a moon with the orbit of Callisto," said Cloutier. "On the other hand, it would have been very difficult for Saturn to do so because Iapetus would have been excessively unsettled, resulting in an orbit that is difficult to reconcile with its current trajectory." The computer model showed that there's about a 42 percent chance that Callisto would have its current orbit around Jupiter if it had been involved in the planetary ejection. The results have been published in The Astrophysical Journal. But to be clear, this doesn't mean that we have any evidence this interaction actually took place, or even that there was an extra planet in the Solar System in the first place. This is all based off computer models, and while they can explain the current state of the planets in our Solar System, they're not the only possibilities out there. "We do know that rogue planets roam the galaxy, and they were almost certainly ejected in this manner, so the idea of a lost solar system planet isn’t crazy," wrote astronomer Phil Plait for Discover back in 2011 when the missing planet hypothesis was first proposed. "But it’s only one possible scenario." Still, it's kind of cool to think that, somewhere out there in the galaxy, a frozen ice giant is roaming, a lost remnant from the formation of our Solar System.
  12. A very interesting placement friend Maw!
  13. Saturn is the sixth planet from the Sun and the second largest planet in our solar system. Adorned with a dazzling system of icy rings, Saturn is unique among the planets. It is not the only planet to have rings, but none are as spectacular or as complex as Saturn's. Like fellow gas giant Jupiter, Saturn is a massive ball made mostly of hydrogen and helium. Surrounded by more than 80 known moons, Saturn is home to some of the most fascinating landscapes in our solar system. From the jets of water that spray from Enceladus to the methane lakes on smoggy Titan, the Saturn system is a rich source of scientific discovery and still holds many mysteries. Saturn is a gas giant made up mostly of hydrogen and helium. Saturn's volume is greater than 760 Earths, and it is the second most massive planet in the solar system, about 95 times Earth's mass. The Ringed Planet is the least dense of all the planets, and is the only one less dense than water. If there were a bathtub big enough to hold it, Saturn would float. The yellow and gold bands seen in Saturn's atmosphere are the result of superfast winds in the upper atmosphere, which can reach up to 1,100 mph (1,800 km/h) around its equator, combined with heat rising from the planet's interior. Saturn rotates about once every 10.5 hours. This means that we, amateur astrophotographers, should not film it for more than 90 seconds, under penalty of possible details running out, the longest footage should use the derrotation technique. The planet's high-speed spin causes Saturn to bulge at its equator and flatten at its poles. The planet is around 75,000 miles (120,000 kilometers) across at its equator, and 68,000 miles (109,000 km) from pole to pole. Saturn's environment is not conducive to life as we know it. The temperatures, pressures and materials that characterize this planet are most likely too extreme and volatile for organisms to adapt to. While planet Saturn is an unlikely place for living things to take hold, the same is not true of some of its many moons. Satellites like Enceladus and Titan, home to internal oceans, could possibly support life. These are just some curiosities of the Lord of the Rings!
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.