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#esa

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Tom Hayward<p>I'm listening to a talk at EPS-DPP by someone from <a href="https://mastodon.social/tags/esa" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>esa</span></a><br>Can anyone tell me the secret of how the flags along the bottom of the slides are sorted?<br>🇩🇪🇦🇹🇧🇪🇩🇰🇪🇸...🇨🇦</p><p>I'd love to know!</p><p>(<span class="h-card" translate="no"><a href="https://feddit.nl/c/esa" class="u-url mention" rel="nofollow noopener" target="_blank">@<span>esa</span></a></span> <span class="h-card" translate="no"><a href="https://mastodon.social/@vicgrinberg" class="u-url mention" rel="nofollow noopener" target="_blank">@<span>vicgrinberg</span></a></span> et al.?)</p>
Starry Time Podcast<p>This is the Needle Galaxy (IC 2233) located 40 million LY in the <a href="https://universeodon.com/tags/constellation" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>constellation</span></a> <a href="https://universeodon.com/tags/Lynx" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>Lynx</span></a> 🤩 </p><p>to learn more about the amazing <a href="https://universeodon.com/tags/astronomy" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astronomy</span></a> within the <a href="https://universeodon.com/tags/constellation" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>constellation</span></a> lynx, check out our <a href="https://universeodon.com/tags/podcast" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>podcast</span></a> episode here: <a href="https://starrytimepodcast.podbean.com/e/cosmic-background-lynx/" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">starrytimepodcast.podbean.com/</span><span class="invisible">e/cosmic-background-lynx/</span></a></p><p>📷 :<a href="https://esahubble.org/images/potw1251a/" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">esahubble.org/images/potw1251a</span><span class="invisible">/</span></a></p><p><a href="https://universeodon.com/tags/AstroDon" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>AstroDon</span></a> <a href="https://universeodon.com/tags/Astronomy" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>Astronomy</span></a> <a href="https://universeodon.com/tags/space" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>space</span></a> <a href="https://universeodon.com/tags/science" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>science</span></a> <a href="https://universeodon.com/tags/Hubble" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>Hubble</span></a> <a href="https://universeodon.com/tags/ESA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>ESA</span></a> <a href="https://universeodon.com/tags/NASA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>NASA</span></a> <a href="https://universeodon.com/tags/astrophotography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astrophotography</span></a></p>
Dr. Victoria Grinberg<p>Call for Expression of Interest to become a member of the European Space Agency Science Advisory Structure:</p><p>▶️ <a href="https://www.cosmos.esa.int/web/expression-of-interest-for-science-advisory-members-2025" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://www.</span><span class="ellipsis">cosmos.esa.int/web/expression-</span><span class="invisible">of-interest-for-science-advisory-members-2025</span></a></p><p>Through the present Call, the <a href="https://mastodon.social/tags/ESA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>ESA</span></a> Director of Science invites scientists affiliated with institutions in the ESA Member States to express their interest in being a member of the Space Science Advisory Committee (SSAC), Astronomy Working Group (AWG), or the Solar System and Exploration Working Group (SSEWG).</p><p><a href="https://mastodon.social/tags/astrodon" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astrodon</span></a> <a href="https://mastodon.social/tags/SpaceScience" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>SpaceScience</span></a></p>
grobi<p>As seen from Earth, the comet was in the northern sky from September until mid-November. It crossed the ecliptic plane on 26 October near the star Regulus, and the celestial equator on 13 November 2019, entering the southern sky. On 8 December 2019, the comet reached perihelion (closest approach to the Sun) and was near the inner edge of the asteroid belt. In late December, it made its closest approach to Earth, 1.9 au, and had a solar elongation of about 80°. Due to its 44° orbital inclination, 2I/Borisov did not make any notable close approaches to the planets. 2I/Borisov entered the Solar System from the direction of Cassiopeia near the border with Perseus. This direction indicates that it originates from the galactic plane, rather than from the galactic halo. It will leave the Solar System in the direction of Telescopium. In interstellar <a href="https://defcon.social/tags/space" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>space</span></a>, 2I/Borisov takes roughly 9000 years to travel a light-year relative to the Sun</p><p>2I/Borisov's trajectory is extremely hyperbolic, having an orbital eccentricity of 3.36. This is much higher than the 300+ known weakly hyperbolic comets, with heliocentric eccentricities just over 1, and even ʻOumuamua with an eccentricity of 1.2.<br>2I/Borisov also has a hyperbolic excess velocity ( v ∞ {\displaystyle v_{\infty }}) of 32 km/s, much higher than what could be explained by perturbations, which could produce velocities when approaching an infinite distance from the Sun of less than a few km/s. These two parameters are important indicators of 2I/Borisov's interstellar origin. For comparison, the Voyager 1 spacecraft, which is leaving the Solar System, is traveling at 16.9 km/s (3.57 AU/a). 2I/Borisov has a much larger eccentricity than ʻOumuamua due to its higher excess velocity and its significantly higher perihelion distance. At this larger distance, the Sun's gravity is less able to alter its path as it passes through the Solar System.</p><p>From Wikipedia</p><p><a href="https://defcon.social/tags/comets" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>comets</span></a> <a href="https://defcon.social/tags/astrophotography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astrophotography</span></a> <a href="https://defcon.social/tags/photography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>photography</span></a> <a href="https://defcon.social/tags/science" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>science</span></a> <a href="https://defcon.social/tags/astronomy" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astronomy</span></a> <a href="https://defcon.social/tags/nature" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>nature</span></a> <a href="https://defcon.social/tags/NASA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>NASA</span></a> <a href="https://defcon.social/tags/ESA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>ESA</span></a></p>
grobi<p>From Wikipedia, the free encyclopedia</p><p>2I/Borisov</p><p>2I/Borisov, originally designated C/2019 Q4 (Borisov), is the first observed rogue comet and the second observed interstellar interloper after ʻOumuamua. It was discovered by the Crimean amateur astronomer and telescope maker Gennadiy Borisov on 29 August 2019 UTC (30 August local time).</p><p>2I/Borisov has a heliocentric orbital eccentricity of 3.36 and is not bound to the Sun. The comet passed through the ecliptic of the Solar System at the end of October 2019, and made its closest approach to the Sun at just over 2 AU on 8 December 2019. The comet passed closest to Earth on 28 December 2019.</p><p>In November 2019, astronomers from Yale University said that the comet's tail was 14 times the size of Earth, and stated, "It's humbling to realize how small Earth is next to this visitor from another solar system."</p><p>The comet is formally called "2I/Borisov" by the International Astronomical Union (IAU), with "2I" or "2I/2019 Q4" being its designation and "Borisov" being its name, but is sometimes referred to as "Comet Borisov", especially in the popular press. As the second observed interstellar interloper after 1I/ʻOumuamua, it was given the "2I" designation, where "I" stands for interstellar. The name Borisov follows the tradition of naming comets after their discoverers. Before final designation as 2I/Borisov, the object was referred to by other names: <br>gb00234<br>C/2019 Q4 </p><p><a href="https://en.wikipedia.org/wiki/2I/Borisov#Nomenclature" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">en.wikipedia.org/wiki/2I/Boris</span><span class="invisible">ov#Nomenclature</span></a></p><p><a href="https://defcon.social/tags/space" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>space</span></a> <a href="https://defcon.social/tags/comets" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>comets</span></a> <a href="https://defcon.social/tags/astrophotography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astrophotography</span></a> <a href="https://defcon.social/tags/photography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>photography</span></a> <a href="https://defcon.social/tags/science" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>science</span></a> <a href="https://defcon.social/tags/astronomy" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astronomy</span></a> <a href="https://defcon.social/tags/nature" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>nature</span></a> <a href="https://defcon.social/tags/NASA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>NASA</span></a> <a href="https://defcon.social/tags/ESA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>ESA</span></a></p>
grobi<p>From Contributors to Wikimedia projects</p><p>1I/ʻOumuamua<br> <br>is the first confirmed interstellar object detected passing through the Solar System. Formally designated 1I/2017 U1, it was discovered by Robert Weryk using the Pan-STARRS telescope at Haleakalā Observatory, Hawaii, on 19 October 2017, approximately 40 days after it passed its closest point to the Sun on 9 September. When it was first observed, it was about 33 million km (21 million mi; 0.22 AU) from Earth (about 85 times as far away as the Moon) and already heading away from the Sun.</p><p>ʻOumuamua is a small object estimated to be between 100 and 1,000 metres (328 and 3,280 ft) long, with its width and thickness both estimated between 35 and 167 metres (115 and 548 ft). It has a red color, like objects in the outer Solar System. Despite its close approach to the Sun, it showed no signs of having a coma, the usual nebula around comets formed when they pass near the Sun. Further, it exhibited non‑gravitational acceleration, potentially due to outgassing or a push from solar radiation pressure.<br>It has a rotation rate similar to the Solar System's asteroids, but many valid models permit it to be unusually more elongated than all but a few other natural bodies observed in the solar system. This feature raised speculation about its origin. Its light curve, assuming little systematic error, presents its motion as "tumbling" rather than "spinning", and moving sufficiently fast relative to the Sun that it is likely of extrasolar origin. Extrapolated and without further deceleration, its path cannot be captured into a solar orbit, so it will eventually leave the Solar System and continue into interstellar space. Its planetary system of origin and age are unknown. [...]</p><p><a href="https://en.wikipedia.org/wiki/1I/%CA%BBOumuamua" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">en.wikipedia.org/wiki/1I/%CA%B</span><span class="invisible">BOumuamua</span></a></p><p>Image Credit:<br>By Tomruen <a href="https://commons.wikimedia.org/w/index.php?curid=64846159" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">commons.wikimedia.org/w/index.</span><span class="invisible">php?curid=64846159</span></a></p><p><a href="https://defcon.social/tags/space" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>space</span></a> <a href="https://defcon.social/tags/comets" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>comets</span></a> <a href="https://defcon.social/tags/astrophotography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astrophotography</span></a> <a href="https://defcon.social/tags/photography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>photography</span></a> <a href="https://defcon.social/tags/science" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>science</span></a> <a href="https://defcon.social/tags/astronomy" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astronomy</span></a> <a href="https://defcon.social/tags/nature" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>nature</span></a> <a href="https://defcon.social/tags/NASA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>NASA</span></a> <a href="https://defcon.social/tags/ESA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>ESA</span></a></p>
grobi<p>Four Years Of Nasa Neowise Data</p><p>NASA's Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE) mission has released its fourth year of survey data. Since the mission was restarted in December 2013, after a period of hibernation, the asteroid- and comet-hunter has completely scanned the skies nearly eight times and has observed and characterized 29,375 objects in four years of operations. This total includes 788 near-Earth objects and 136 comets since the mission restart.</p><p>Near-Earth objects (NEOs) are comets and asteroids that have been nudged by the gravitational attraction of the planets in our solar system into orbits that allow them to enter Earth's neighborhood. Ten of the objects discovered by NEOWISE in the past year have been classified as potentially hazardous asteroids (PHAs). Near-Earth objects are classified as PHAs, based on their size and how closely they can approach Earth's orbit.</p><p>"NEOWISE continues to expand our catalog and knowledge of these elusive and important objects," said Amy Mainzer, NEOWISE principal investigator from NASA's Jet Propulsion Laboratory in Pasadena, California. "In total, NEOWISE has now characterized sizes and reflectivities of over 1,300 near-Earth objects since the spacecraft was launched, offering an invaluable resource for understanding the physical properties of this population, and studying what they are made of and where they have come from."</p><p>[...]</p><p>More than 2.5 million infrared images of the sky were collected in the fourth year of operations by NEOWISE. These data are combined with the year one through three NEOWISE data into a single publicly available archive. That archive contains approximately 10.3 million sets of images and a database of more than 76 billion source detections extracted from those images.</p><p><a href="https://www.jpl.nasa.gov/news/four-years-of-nasa-neowise-data/" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://www.</span><span class="ellipsis">jpl.nasa.gov/news/four-years-o</span><span class="invisible">f-nasa-neowise-data/</span></a></p><p>CREDIT<br>Jet Propulsion Laboratory</p><p><a href="https://defcon.social/tags/space" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>space</span></a> <a href="https://defcon.social/tags/comets" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>comets</span></a> <a href="https://defcon.social/tags/astrophotography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astrophotography</span></a> <a href="https://defcon.social/tags/photography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>photography</span></a> <a href="https://defcon.social/tags/science" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>science</span></a> <a href="https://defcon.social/tags/astronomy" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astronomy</span></a> <a href="https://defcon.social/tags/nature" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>nature</span></a> <a href="https://defcon.social/tags/NASA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>NASA</span></a> <a href="https://defcon.social/tags/ESA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>ESA</span></a></p>
grobi<p>June 30, 2017</p><p>NASA Planetary Defense:<br>Backyard Asteroid Observer</p><p>Backyard astronomer Robert Holmes of Westfield, Illinois, is part of NASA's army of observers scanning the night sky for asteroids.</p><p>"We do follow-up observations with NASA's near-Earth observations program. All night long, I'm running big telescopes. One's a 24-inch, a 30-inch, and a 32-inch. And then the 50 inch is my… my biggest telescope [...]."</p><p>"[...] We do follow-up observations for the discoveries that are made by the large sky surveys. By looking at these asteroids, and measuring these asteroids, we can determine what their possibilities of actually hitting the Earth in the future are going to be.</p><p>NASA provides coordinates of specific objects that they need observations on. I'm gonna punch in the coordinates here, and I'm doing this remotely from inside a control room, not at the telescope. And so, we look these objects up and then use those coordinates to look at a tiny piece of the sky that this object happens to be in. And then we follow those objects, and define and refine orbits for those objects, and reduce the uncertainty of where it's going to go in the near future.</p><p>I started off as a volunteer in 2006. It's just blossomed into a full-time opportunity to work for NASA under their grant program, where I'm now doing this every single clear night.</p><p>Now we're starting the observing run for 2017 KK3. You don't build a telescope that's this big without having… being passionate about what you do. I'm really driven to be a part of a program that's important and has importance to the future. And we're not talking about next year or the year after, We're talking about asteroids that could potentially hit the Earth 100 years from now. And the work we do today may make a difference 100 years from now."</p><p><a href="https://www.jpl.nasa.gov/videos/nasa-planetary-defense-backyard-asteroid-observer/" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://www.</span><span class="ellipsis">jpl.nasa.gov/videos/nasa-plane</span><span class="invisible">tary-defense-backyard-asteroid-observer/</span></a></p><p>FYI:<br><a href="https://science.nasa.gov/planetary-defense/" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">science.nasa.gov/planetary-def</span><span class="invisible">ense/</span></a></p><p>CREDIT<br>Jet Propulsion Laboratory</p><p><a href="https://defcon.social/tags/space" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>space</span></a> <a href="https://defcon.social/tags/comets" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>comets</span></a> <a href="https://defcon.social/tags/astrophotography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astrophotography</span></a> <a href="https://defcon.social/tags/photography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>photography</span></a> <a href="https://defcon.social/tags/science" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>science</span></a> <a href="https://defcon.social/tags/astronomy" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astronomy</span></a> <a href="https://defcon.social/tags/nature" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>nature</span></a> <a href="https://defcon.social/tags/NASA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>NASA</span></a> <a href="https://defcon.social/tags/ESA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>ESA</span></a> <a href="https://defcon.social/tags/security" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>security</span></a> <a href="https://defcon.social/tags/tech" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>tech</span></a></p>
grobi<p>Nov. 20, 2017</p><p>Solar Systems First Interstellar Visitor Dazzles Scientists </p><p>Astronomers scrambled to observe an intriguing asteroid that zipped through the solar system on a steep trajectory from interstellar space-the first confirmed object from another star.</p><p>Now, new data reveal the interstellar interloper to be a rocky, cigar-shaped object with a somewhat reddish hue. The asteroid, named 'Oumuamua by its discoverers, is up to one-quarter mile (400 meters) long and highly-elongated-perhaps 10 times as long as it is wide. That aspect ratio is greater than that of any asteroid or comet observed in our solar system to date. While its elongated shape is quite surprising, and unlike asteroids seen in our solar system, it may provide new clues into how other solar systems formed.</p><p>The observations and analyses were funded in part by NASA and appear in the Nov. 20 issue of the journal Nature. They suggest this unusual object had been wandering through the Milky Way, unattached to any star system, for hundreds of millions of years before its chance encounter with our star system.</p><p>"For decades we've theorized that such interstellar objects are out there, and now - for the first time - we have direct evidence they exist," said Thomas Zurbuchen, associate administrator for NASA's Science Mission Directorate in Washington. "This history-making discovery is opening a new window to study formation of solar systems beyond our own."</p><p>Immediately after its discovery, telescopes around the world, including ESO's Very Large Telescope in Chile, were called into action to measure the object's orbit, brightness and color. Urgency for viewing from ground-based telescopes was vital to get the best data.</p><p>Combining the images from the FORS instrument on the ESO telescope using four different [...]</p><p><a href="https://www.jpl.nasa.gov/news/solar-systems-first-interstellar-visitor-dazzles-scientists/" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://www.</span><span class="ellipsis">jpl.nasa.gov/news/solar-system</span><span class="invisible">s-first-interstellar-visitor-dazzles-scientists/</span></a></p><p>CREDIT<br>Jet Propulsion Laboratory</p><p><a href="https://defcon.social/tags/space" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>space</span></a> <a href="https://defcon.social/tags/comets" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>comets</span></a> <a href="https://defcon.social/tags/astrophotography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astrophotography</span></a> <a href="https://defcon.social/tags/photography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>photography</span></a> <a href="https://defcon.social/tags/science" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>science</span></a> <a href="https://defcon.social/tags/astronomy" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astronomy</span></a> <a href="https://defcon.social/tags/nature" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>nature</span></a> <a href="https://defcon.social/tags/NASA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>NASA</span></a> <a href="https://defcon.social/tags/ESA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>ESA</span></a></p>
grobi<p>2017 November 22</p><p>'Oumuamua: Interstellar Asteroid<br> * Illustration Credit: European Southern Observatory, M. Kornmesser<br><a href="http://www.eso.org/public/" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">http://www.</span><span class="">eso.org/public/</span><span class="invisible"></span></a></p><p>Explanation: <br>Nothing like it has ever been seen before. The unusual space rock 'Oumuamua is so intriguing mainly because it is the first asteroid ever detected from outside our Solar System -- although likely many more are to follow given modern computer-driven sky monitoring. Therefore humanity's telescopes -- of nearly every variety -- have put 'Oumuamua into their observing schedule to help better understand this unusual interstellar visitor. Pictured is an artist's illustration of what 'Oumuamua might look like up close. 'Oumuamua is also intriguing, however, because it has unexpected parallels to Rama, a famous fictional interstellar spaceship created by the late science fiction writer Arthur C. Clarke. Like Rama, 'Oumuamua is unusually elongated, should be made of strong material to avoid breaking apart, is only passing through our Solar System, and passed unusually close to the Sun for something gravitationally unbound. Unlike a visiting spaceship, though, 'Oumuamua's trajectory, speed, color, and even probability of detection are consistent with it forming naturally around a normal star many millions of years ago, being expelled after gravitationally encountering a normal planet, and subsequently orbiting in our Galaxy alone. Even given 'Oumuamua's likely conventional origin, perhaps humanity can hold hope that one day we will have the technology to engineer 'Oumuamua -- or another Solar System interloper -- into an interstellar Rama of our own. <br><a href="https://www.eso.org/public/news/eso1737/" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://www.</span><span class="">eso.org/public/news/eso1737/</span><span class="invisible"></span></a><br><a href="https://www.jpl.nasa.gov/news/solar-systems-first-interstellar-visitor-dazzles-scientists/" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://www.</span><span class="ellipsis">jpl.nasa.gov/news/solar-system</span><span class="invisible">s-first-interstellar-visitor-dazzles-scientists/</span></a><br><a href="https://en.wikipedia.org/wiki/1I/%CA%BBOumuamua" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">en.wikipedia.org/wiki/1I/%CA%B</span><span class="invisible">BOumuamua</span></a><br><a href="https://arxiv.org/abs/1711.04927" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="">arxiv.org/abs/1711.04927</span><span class="invisible"></span></a><br><a href="https://arxiv.org/abs/1710.11364" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="">arxiv.org/abs/1710.11364</span><span class="invisible"></span></a></p><p><a href="https://apod.nasa.gov/apod/ap171122.html" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">apod.nasa.gov/apod/ap171122.ht</span><span class="invisible">ml</span></a></p><p><a href="https://defcon.social/tags/space" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>space</span></a> <a href="https://defcon.social/tags/comets" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>comets</span></a> <a href="https://defcon.social/tags/astrophotography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astrophotography</span></a> <a href="https://defcon.social/tags/photography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>photography</span></a> <a href="https://defcon.social/tags/science" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>science</span></a> <a href="https://defcon.social/tags/astronomy" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astronomy</span></a> <a href="https://defcon.social/tags/nature" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>nature</span></a> <a href="https://defcon.social/tags/NASA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>NASA</span></a> <a href="https://defcon.social/tags/ESA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>ESA</span></a></p>
grobi<p>List of TOPICS&gt; No1</p><p>Hey Friends Of Space,<br>Would you like to accompany me through the time/space continuum, through the archives of NASA, ESA and on their missions? <br>Or do we want to watch atmospheric or electrostatic light shows on our home planet together? <br>Join me on my journey and feel free to bookmark or even boost the first of my following "TOPIC&gt; lists" <br>This list will be updated and edited regularly.</p><p>1. TOPIC&gt; Airglows<br><a href="https://defcon.social/@grobi/114617603184721208" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">defcon.social/@grobi/114617603</span><span class="invisible">184721208</span></a></p><p>2. TOPIC&gt; Stars On A Trail<br><a href="https://defcon.social/@grobi/114538103004457677" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">defcon.social/@grobi/114538103</span><span class="invisible">004457677</span></a><br>++ Starting Music Video<br><a href="https://defcon.social/@grobi/114541184131537630" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">defcon.social/@grobi/114541184</span><span class="invisible">131537630</span></a></p><p>3. TOPIC&gt; Auroras<br><a href="https://defcon.social/@grobi/114646611195811889" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">defcon.social/@grobi/114646611</span><span class="invisible">195811889</span></a></p><p>4. TOPIC&gt; Face On<br><a href="https://defcon.social/@grobi/114645916621233026" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">defcon.social/@grobi/114645916</span><span class="invisible">621233026</span></a></p><p>5. TOPIC&gt; On The Edge<br><a href="https://defcon.social/@grobi/114492980977318959" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">defcon.social/@grobi/114492980</span><span class="invisible">977318959</span></a></p><p>6. TOPIC&gt;<br>Supermassive Black Holes<br><a href="https://defcon.social/@grobi/114448092463278757" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">defcon.social/@grobi/114448092</span><span class="invisible">463278757</span></a></p><p>7. TOPIC&gt; Novae<br><a href="https://defcon.social/@grobi/114787530730178263" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">defcon.social/@grobi/114787530</span><span class="invisible">730178263</span></a></p><p>8. TOPIC&gt; <br>Formations Nebulae Pillars<br><a href="https://defcon.social/@grobi/114696771234606419" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">defcon.social/@grobi/114696771</span><span class="invisible">234606419</span></a></p><p>9. TOPIC&gt; <br>In The Neighbourhood<br><a href="https://defcon.social/@grobi/114555536815890569" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">defcon.social/@grobi/114555536</span><span class="invisible">815890569</span></a></p><p>10. TOPIC&gt;<br>Gravitational Lensing<br><a href="https://defcon.social/@grobi/114374350096488478" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">defcon.social/@grobi/114374350</span><span class="invisible">096488478</span></a></p><p>11. TOPIC&gt; "Bull's Eye" into the Center of our Galaxy<br><a href="https://defcon.social/@grobi/114498597554595255" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">defcon.social/@grobi/114498597</span><span class="invisible">554595255</span></a></p><p>12. TOPIC&gt; Interstellar Visitors</p><p><a href="https://defcon.social/@grobi/114810072977625219" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">defcon.social/@grobi/114810072</span><span class="invisible">977625219</span></a></p><p>13. TOPIC&gt; Mars<br><a href="https://defcon.social/@grobi/114685732221738874" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">defcon.social/@grobi/114685732</span><span class="invisible">221738874</span></a></p><p>14. TOPIC&gt; Jupiter<br><a href="https://defcon.social/@grobi/114553098434558723" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">defcon.social/@grobi/114553098</span><span class="invisible">434558723</span></a></p><p>15. TOPIC&gt; Moons Of Saturn<br><a href="https://defcon.social/@grobi/114442269890667602" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">defcon.social/@grobi/114442269</span><span class="invisible">890667602</span></a></p><p>16. TOPIC&gt; About Pluto<br><a href="https://defcon.social/@grobi/114509950451766236" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">defcon.social/@grobi/114509950</span><span class="invisible">451766236</span></a></p><p>17. TOPIC&gt; Space Culture Club<br><a href="https://defcon.social/@grobi/114663418339078163" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">defcon.social/@grobi/114663418</span><span class="invisible">339078163</span></a></p><p>18. TOPIC&gt; Useful Code<br><a href="https://defcon.social/@grobi/114797042323081686" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">defcon.social/@grobi/114797042</span><span class="invisible">323081686</span></a></p><p><a href="https://defcon.social/tags/space" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>space</span></a> <a href="https://defcon.social/tags/astrophotography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astrophotography</span></a> <a href="https://defcon.social/tags/photography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>photography</span></a> <a href="https://defcon.social/tags/sience" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>sience</span></a> <a href="https://defcon.social/tags/astronomy" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astronomy</span></a> <a href="https://defcon.social/tags/nature" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>nature</span></a> <a href="https://defcon.social/tags/fediverse" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>fediverse</span></a> <a href="https://defcon.social/tags/mastodon" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>mastodon</span></a> <a href="https://defcon.social/tags/NASA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>NASA</span></a> <a href="https://defcon.social/tags/ESA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>ESA</span></a> <a href="https://defcon.social/tags/nobot" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>nobot</span></a> <a href="https://defcon.social/tags/noai" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>noai</span></a> <a href="https://defcon.social/tags/list" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>list</span></a></p>
grobi<p>What We Know About Interstellar Comet 3I/ATLAS</p><p>An interstellar traveler has been discovered passing through our solar system. The NASA-funded ATLAS (Asteroid Terrestrial-impact Last Alert System) survey telescope in Rio Hurtado, Chile, first reported observations of comet 3I/ATLAS on July 1, 2025. Since the first report, additional observations from before the discovery were gathered from the archives of three ATLAS telescopes around the world and Caltech’s Zwicky Transient Facility at the Palomar Observatory in San Diego County, California. These “pre-discovery” observations extend back to June 14. The fast-moving comet, which originated outside our solar system around a different star, was discovered as a tiny speck moving across the vastness of space. When discovered it was about 410 million miles (670 million kilometers) away from the Sun, within the orbit of Jupiter. </p><p>This is the third interstellar object ever discovered, hence its name begins with the number 3 and the letter I. Scientists will have several months to observe and study the comet as it passes through our solar system and before it exits. As of July 3, 2025, the comet is just inside the orbit of Jupiter and in late October 2025 it will make its closest approach to our sun from just inside the orbit of Mars. It poses no threat to Earth but offers a fascinating and rare opportunity for scientists to study these interstellar interlopers.</p><p><a href="https://science.nasa.gov/solar-system/comets/3i-atlas/" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">science.nasa.gov/solar-system/</span><span class="invisible">comets/3i-atlas/</span></a></p><p>CREDIT:<br>NASA Jet Propulsion Laboratory</p><p><a href="https://defcon.social/tags/space" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>space</span></a> <a href="https://defcon.social/tags/comets" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>comets</span></a> <a href="https://defcon.social/tags/astrophotography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astrophotography</span></a> <a href="https://defcon.social/tags/photography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>photography</span></a> <a href="https://defcon.social/tags/science" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>science</span></a> <a href="https://defcon.social/tags/astronomy" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astronomy</span></a> <a href="https://defcon.social/tags/nature" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>nature</span></a> <a href="https://defcon.social/tags/NASA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>NASA</span></a> <a href="https://defcon.social/tags/ESA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>ESA</span></a></p>
grobi<p>Where did this interstellar object come from?</p><p>3I/ATLAS formed in another star system and was somehow ejected into interstellar space, which is the space between the stars. For millions or even billions of years, it has drifted until it recently arrived at our solar system. It has been approaching from the general direction of the constellation Sagittarius, which is where the central region of our galaxy, the Milky Way, is located. When discovered, 3I/ATLAS was about 410 million miles (670 million kilometers) away from the Sun, within the orbit of Jupiter.</p><p>How was it determined that 3I/ATLAS didn’t originate in our solar system?</p><p>Observations of the comet’s trajectory show that it is moving too fast to be bound by the Sun’s gravity and that it's on what is known as a hyperbolic trajectory. In other words, it does not follow a closed orbital path around the Sun. It is simply passing through our solar system and will continue its journey into interstellar space, never to be seen again.</p><p>How many interstellar objects have been discovered?</p><p>This is the third known interstellar object to have been observed. Discovered in 2017, ‘Oumuamua was the first known interstellar object; the second was 2I/Borisov, which was discovered in 2019.</p><p>How big is 3I/ATLAS, and is it an asteroid or comet?</p><p>Astronomers don’t yet know how big 3I/ATLAS is, but from observations, they can see that it’s active, which means it has an icy nucleus and coma (a bright cloud of gas and dust surrounding a comet as it approaches the Sun). This is why astronomers categorize it as a comet and not an asteroid.</p><p>How fast is it moving?</p><p>Very fast. When it was discovered, the interstellar comet was traveling about 137,000 miles per hour (221,000 kilometers per hour, or 61 kilometers per second), and its speed will increase as it approaches the Sun.</p><p>CREDIT:<br>ATLAS/University of Hawaii/NASA</p><p><a href="https://science.nasa.gov/solar-system/comets/3i-atlas/" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">science.nasa.gov/solar-system/</span><span class="invisible">comets/3i-atlas/</span></a></p><p><a href="https://defcon.social/tags/space" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>space</span></a> <a href="https://defcon.social/tags/comets" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>comets</span></a> <a href="https://defcon.social/tags/astrophotography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astrophotography</span></a> <a href="https://defcon.social/tags/photography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>photography</span></a> <a href="https://defcon.social/tags/science" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>science</span></a> <a href="https://defcon.social/tags/astronomy" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astronomy</span></a> <a href="https://defcon.social/tags/nature" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>nature</span></a> <a href="https://defcon.social/tags/NASA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>NASA</span></a> <a href="https://defcon.social/tags/ESA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>ESA</span></a></p>
grobi<p>ESA tracks rare interstellar comet</p><p>Space Safety<br>03/07/2025</p><p>Astronomers have confirmed the discovery of a rare celestial visitor: a comet from beyond our Solar System.</p><p>Officially named 3I/ATLAS, this newly identified interstellar object is only the third of its kind ever observed, following the famous 1I/ʻOumuamua in 2017 and 2I/Borisov in 2019.<br>A visitor from beyond the void</p><p>The comet was first spotted on 1 July 2025 by the Asteroid Terrestrial-impact Last Alert System (ATLAS) telescope in Río Hurtado, Chile. Its unusual trajectory immediately raised suspicions that it originated from interstellar space. This was later confirmed by astronomers around the world, and the object was given its formal designation: 3I/ATLAS, indicating its status as the third known interstellar object.</p><p>3I/ATLAS is approximately 670 million kilometres from the Sun and will make its closest approach in late October 2025, passing just inside the orbit of Mars. It is thought to be up to 20 kilometres wide and is travelling roughly 60 km/s relative to the Sun. It poses no danger to Earth, coming no closer than 240 million kilometres – over 1.5 times the distance between Earth and the Sun.</p><p>CREDIT:<br>ESA<br><a href="https://www.esa.int/Space_Safety/Planetary_Defence/ESA_tracks_rare_interstellar_comet" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://www.</span><span class="ellipsis">esa.int/Space_Safety/Planetary</span><span class="invisible">_Defence/ESA_tracks_rare_interstellar_comet</span></a></p><p><a href="https://defcon.social/tags/space" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>space</span></a> <a href="https://defcon.social/tags/comets" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>comets</span></a> <a href="https://defcon.social/tags/astrophotography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astrophotography</span></a> <a href="https://defcon.social/tags/photography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>photography</span></a> <a href="https://defcon.social/tags/science" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>science</span></a> <a href="https://defcon.social/tags/astronomy" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astronomy</span></a> <a href="https://defcon.social/tags/nature" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>nature</span></a> <a href="https://defcon.social/tags/NASA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>NASA</span></a> <a href="https://defcon.social/tags/ESA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>ESA</span></a></p>
grobi<p>TOPIC&gt; Interstellar Visitors</p><p>2025 July 7<br>A drawing of our Solar System shows the orbits of Jupiter and interior planets. A white line shows the trajectory of passing comet 3I/ATLAS. </p><p>Interstellar Comet 3I/ATLAS<br> * Image Credit: NASA, JPL-Caltech<br><a href="https://www.jpl.nasa.gov/" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://www.</span><span class="">jpl.nasa.gov/</span><span class="invisible"></span></a><br><a href="https://www.nasa.gov/" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://www.</span><span class="">nasa.gov/</span><span class="invisible"></span></a></p><p>Explanation: <br>It came from outer space. An object from outside our Solar System is now passing through at high speed. Classified as a comet because of its gaseous coma, 3I/ATLAS is only the third identified macroscopic object as being so alien. The comet's trajectory is shown in white on the featured map, where the orbits of Jupiter, Mars, and Earth are shown in gold, red, and blue. Currently Comet 3I/ATLAS is about the distance of Jupiter from the Sun -- but closing, with its closest approach to our Sun expected to be within the orbit of Mars in late October. Expected to pass near both Mars and Jupiter, 3I/ATLAS is not expected to pass close to the Earth. The origin of Comet 3I/ATLAS remains unknown. Although initial activity indicates a relatively normal comet, future observations about 3I/ATLAS' composition and nature will surely continue.<br><a href="https://www.esa.int/Space_Safety/Planetary_Defence/ESA_tracks_rare_interstellar_comet" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://www.</span><span class="ellipsis">esa.int/Space_Safety/Planetary</span><span class="invisible">_Defence/ESA_tracks_rare_interstellar_comet</span></a><br><a href="https://en.wikipedia.org/wiki/3I/ATLAS" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="">en.wikipedia.org/wiki/3I/ATLAS</span><span class="invisible"></span></a><br><a href="https://science.nasa.gov/solar-system/comets/3i-atlas/" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">science.nasa.gov/solar-system/</span><span class="invisible">comets/3i-atlas/</span></a></p><p><a href="https://apod.nasa.gov/apod/ap191018.html" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">apod.nasa.gov/apod/ap191018.ht</span><span class="invisible">ml</span></a></p><p>Our Solar System:<br><a href="https://science.nasa.gov/solar-system/" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="">science.nasa.gov/solar-system/</span><span class="invisible"></span></a><br><a href="https://science.nasa.gov/jupiter/" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="">science.nasa.gov/jupiter/</span><span class="invisible"></span></a><br><a href="https://science.nasa.gov/mars/" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="">science.nasa.gov/mars/</span><span class="invisible"></span></a></p><p><a href="https://www.swri.org/newsroom/press-releases/ibex-spacecraft-measures-alien-particles-outside-solar-system-reveals-interactions-surrounding-regions" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://www.</span><span class="ellipsis">swri.org/newsroom/press-releas</span><span class="invisible">es/ibex-spacecraft-measures-alien-particles-outside-solar-system-reveals-interactions-surrounding-regions</span></a></p><p><a href="https://apod.nasa.gov/apod/ap250707.html" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">apod.nasa.gov/apod/ap250707.ht</span><span class="invisible">ml</span></a></p><p><a href="https://defcon.social/tags/space" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>space</span></a> <a href="https://defcon.social/tags/comets" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>comets</span></a> <a href="https://defcon.social/tags/astrophotography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astrophotography</span></a> <a href="https://defcon.social/tags/photography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>photography</span></a> <a href="https://defcon.social/tags/science" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>science</span></a> <a href="https://defcon.social/tags/astronomy" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astronomy</span></a> <a href="https://defcon.social/tags/nature" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>nature</span></a> <a href="https://defcon.social/tags/NASA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>NASA</span></a> <a href="https://defcon.social/tags/ESA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>ESA</span></a></p>
StellarSnap<p>📸 The Spiral North Pole of Mars<br>Each winter, Mars adds a fresh layer of carbon dioxide ice atop its North Pole. Swirling winds shaped by the planet’s rotation sculpt this spiral form, known as Planum Boreum. Data from ESA’s Mars Express and NASA’s MGS reveal the stunning structure.</p><p>📅 APOD – July 6, 2025<br>📷 ESA/DLR/FU Berlin; NASA MGS MOLA Science Team</p><p><a href="https://mastodon.social/tags/APOD" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>APOD</span></a> <a href="https://mastodon.social/tags/NASA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>NASA</span></a> <a href="https://mastodon.social/tags/ESA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>ESA</span></a> <a href="https://mastodon.social/tags/Mars" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>Mars</span></a> <a href="https://mastodon.social/tags/MarsExpress" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>MarsExpress</span></a> <a href="https://mastodon.social/tags/MGS" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>MGS</span></a> <a href="https://mastodon.social/tags/PlanumBoreum" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>PlanumBoreum</span></a> <a href="https://mastodon.social/tags/RedPlanet" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>RedPlanet</span></a> <a href="https://mastodon.social/tags/Space" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>Space</span></a> <a href="https://mastodon.social/tags/Astronomy" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>Astronomy</span></a> <a href="https://mastodon.social/tags/StellarSnap" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>StellarSnap</span></a> <a href="https://mastodon.social/tags/PlanetaryScience" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>PlanetaryScience</span></a> <a href="https://mastodon.social/tags/Astrophotography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>Astrophotography</span></a> <a href="https://mastodon.social/tags/MarsPole" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>MarsPole</span></a></p>
grobi<p>Finding globular clusters in Euclid’s view of spiral galaxy IC342 </p><p>In Euclid’s image of spiral galaxy IC342, the locations of several globular clusters are shown. Globular clusters are compact collections of hundreds of thousands of stars held together by gravity. Globular clusters tend to be old, with red colors, while star clusters may be less compact and blue. In spiral galaxies, like our Milky Way, these globular clusters are mostly found in the galactic halo.</p><p>from arxiv:</p><p>"We examine the star cluster populations in the three nearby galaxies IC 342, NGC 2403, and Holmberg II, observed as part of the Euclid Early Release Observations programme. Our main focus is on old globular clusters (GCs), for which the wide field-of-view and excellent image quality of Euclid offer substantial advantages over previous work. For IC 342 this is the first study of stellar clusters other than its nuclear cluster. After selection based on size and magnitude criteria, followed by visual inspection, we identify 111 old (&gt; 1 Gyr) GC candidates in IC 342, 50 in NGC 2403 (of which 15 were previously known), [...] "<br><a href="https://arxiv.org/abs/2503.16637" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="">arxiv.org/abs/2503.16637</span><span class="invisible"></span></a><br><a href="https://arxiv.org/pdf/2503.16637" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="">arxiv.org/pdf/2503.16637</span><span class="invisible"></span></a></p><p> * note by grobi: "Could these mass-holding clusters be useful for gravitational lensing? The Euclid team is talking about 7000 possible candidates by the end of 2026 and 100000 candidates by the end of the mission. Which would mean that very soon we will be able to look much further into the depths of space-time than we can even imagine today. <br>Exciting times from an astronomical point of view, right? Feel free to check out the following post from the TOPIC&gt; Gravitational Lensing<br><a href="https://defcon.social/@grobi/114682791891969004" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">defcon.social/@grobi/114682791</span><span class="invisible">891969004</span></a> Enjoy!"</p><p><a href="https://defcon.social/tags/space" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>space</span></a> <a href="https://defcon.social/tags/galaxy" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>galaxy</span></a> <a href="https://defcon.social/tags/astrophotography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astrophotography</span></a> <a href="https://defcon.social/tags/photography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>photography</span></a> <a href="https://defcon.social/tags/science" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>science</span></a> <a href="https://defcon.social/tags/astronomy" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astronomy</span></a> <a href="https://defcon.social/tags/nature" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>nature</span></a> <a href="https://defcon.social/tags/NASA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>NASA</span></a> <a href="https://defcon.social/tags/ESA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>ESA</span></a></p>
grobi<p>IC 342 <br>is located around 11 million light-years from Earth, very nearby our own galaxy (in astronomical distances). It is as large as the full Moon on the sky. And as a spiral galaxy, it is considered a look-alike of the Milky Way. “It is difficult to study our own galaxy as we are within it and can only see it edge on. So, by studying galaxies like IC 342, we can learn a lot about galaxies like our own,” adds Leslie.</p><p>Euclid is not the first to observe the Hidden Galaxy. The NASA/ESA Hubble Space Telescope has previously imaged its core. But until now it has been impossible to study the star-formation history of the entire galaxy. Additionally, scientists have already spotted many globular clusters in this image, some of which have not been previously identified.</p><p>Euclid will observe billions of similar but more distant galaxies, all distributed along a ‘cosmic web’ of dark matter filaments. In this way, it will provide a 3D view of the dark matter distribution in our Universe. The map of the distribution of galaxies over cosmic time will also teach us about dark energy, which accelerates the expansion of the Universe.</p><p>CREDIT<br>ESA/Euclid/Euclid Consortium/NASA, image processing by J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi </p><p><a href="https://defcon.social/tags/space" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>space</span></a> <a href="https://defcon.social/tags/galaxy" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>galaxy</span></a> <a href="https://defcon.social/tags/astrophotography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astrophotography</span></a> <a href="https://defcon.social/tags/photography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>photography</span></a> <a href="https://defcon.social/tags/science" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>science</span></a> <a href="https://defcon.social/tags/astronomy" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astronomy</span></a> <a href="https://defcon.social/tags/nature" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>nature</span></a> <a href="https://defcon.social/tags/NASA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>NASA</span></a> <a href="https://defcon.social/tags/ESA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>ESA</span></a></p>
grobi<p>07/11/2023<br>Euclid’s view of spiral galaxy IC 342</p><p>Over its lifetime, our dark Universe detective will image billions of galaxies, revealing the hidden influence that dark matter and dark energy have on them.</p><p>That’s why it’s fitting that one of the first galaxies that Euclid observed is nicknamed the ‘Hidden Galaxy’. This galaxy, also known as IC 342 or Caldwell 5, is difficult to observe because it lies behind the busy disc of our Milky Way, and so dust, gas and stars obscure our view.</p><p>Euclid could take this beautiful and sharp image thanks to its incredible sensitivity and superb optics. Most important here is that Euclid used its near-infrared instrument to peer through the dust and measure the light from the many cool and low-mass stars that dominate the galaxy's mass.</p><p>“That’s what is so brilliant about Euclid images. In one shot, it can see the whole galaxy in all its beautiful detail,” explains Euclid Consortium scientist Leslie Hunt of the National Institute for Astrophysics in Italy, on behalf of a broader team working on showcasing galaxies imaged by Euclid.</p><p>“This image might look normal, as if every telescope can make such an image, but that is not true. What’s so special here is that we have a wide view covering the entire galaxy, but we can also zoom in to distinguish single stars and star clusters. This makes it possible to trace the history of star formation and better understand how stars formed and evolved over the lifetime of the galaxy.”</p><p>CREDIT<br>ESA/Euclid/Euclid Consortium/NASA, image processing by J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi</p><p><a href="https://defcon.social/tags/space" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>space</span></a> <a href="https://defcon.social/tags/galaxy" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>galaxy</span></a> <a href="https://defcon.social/tags/astrophotography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astrophotography</span></a> <a href="https://defcon.social/tags/photography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>photography</span></a> <a href="https://defcon.social/tags/science" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>science</span></a> <a href="https://defcon.social/tags/astronomy" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astronomy</span></a> <a href="https://defcon.social/tags/nature" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>nature</span></a> <a href="https://defcon.social/tags/NASA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>NASA</span></a> <a href="https://defcon.social/tags/ESA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>ESA</span></a></p>
grobi<p>Multi-observatory views of M74</p><p>New images of the Phantom Galaxy, M74, showcase the power of space observatories working together in multiple wavelengths. <br> * see ALT-Text for more</p><p>Webb’s sharp vision has revealed delicate filaments of gas and dust in the grandiose spiral arms of M74, which wind outwards from the centre of the image. A lack of gas in the nuclear region also provides an unobscured view of the nuclear star cluster at the galaxy's centre.</p><p>Webb gazed into M74 with its Mid-InfraRed Instrument (MIRI) in order to learn more about the earliest phases of star formation in the local Universe. These observations are part of a larger effort to chart 19 nearby star-forming galaxies in the infrared by the international PHANGS collaboration. Those galaxies have already been observed using the NASA/ESA Hubble Space Telescope and ground-based observatories.</p><p>The addition of crystal-clear Webb observations at longer wavelengths will allow astronomers to pinpoint star-forming regions in the galaxies, accurately measure the masses and ages of star clusters, and gain insights into the nature of the small grains of dust drifting in interstellar space.</p><p>
Hubble observations of M74 have revealed particularly bright areas of star formation known as HII regions. Hubble’s sharp vision at ultraviolet and visible wavelengths complements Webb’s unparalleled sensitivity at infrared wavelengths, as do observations from ground-based radio telescopes such as the Atacama Large Millimeter/submillimeter Array, ALMA.</p><p>By combining data from telescopes operating across the electromagnetic spectrum, scientists can gain greater insight into astronomical objects than by using a single observatory – even one as powerful as Webb!</p><p>CREDIT<br>ESA/Webb, NASA &amp; CSA, J. Lee and the PHANGS-JWST Team; ESA/Hubble &amp; NASA, R. Chandar Acknowledgement: J. Schmidt</p><p><a href="https://defcon.social/tags/space" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>space</span></a> <a href="https://defcon.social/tags/galaxy" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>galaxy</span></a> <a href="https://defcon.social/tags/astrophotography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astrophotography</span></a> <a href="https://defcon.social/tags/photography" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>photography</span></a> <a href="https://defcon.social/tags/science" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>science</span></a> <a href="https://defcon.social/tags/astronomy" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>astronomy</span></a> <a href="https://defcon.social/tags/nature" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>nature</span></a> <a href="https://defcon.social/tags/NASA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>NASA</span></a> <a href="https://defcon.social/tags/ESA" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>ESA</span></a></p>