The NGC 3125 Galaxy

<div style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjSHCxdLm7NReK2vriXuTAzaHKWu9hTk18EQBkBGZkCSd-sVsUGWkDtY4V80hl1TYnsJGxHHtNkECLnHb1ZCEJzTjTzWsjTzgp9aI__aXw_uoGLi1gxJdjex3d7a2qzF7VHx0CjKP_aAtZN/s1600/NGC-3125-Galaxy.jpg" imageanchor="1"><img alt="NGC 3125 Galaxy" border="0" height="536" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjSHCxdLm7NReK2vriXuTAzaHKWu9hTk18EQBkBGZkCSd-sVsUGWkDtY4V80hl1TYnsJGxHHtNkECLnHb1ZCEJzTjTzWsjTzgp9aI__aXw_uoGLi1gxJdjex3d7a2qzF7VHx0CjKP_aAtZN/s640/NGC-3125-Galaxy.jpg" title="" width="640" /></a></div><div style="text-align: center;"><br /></div><div style="text-align: center;">This NASA/ESA Hubble Space Telescope image reveals the vibrant core of the galaxy NGC 3125. Discovered by John Herschel in 1835, NGC 3125 is a great example of a starburst galaxy — a galaxy in which unusually high numbers of new stars are forming, springing to life within intensely hot clouds of gas.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">Located approximately 50 million light-years away in the constellation of Antlia (The Air Pump), NGC 3125 is similar to, but unfathomably brighter and more energetic than, one of the Magellanic Clouds. Spanning 15 000 light-years, the galaxy displays massive and violent bursts of star formation, as shown by the hot, young, and blue stars scattered throughout the galaxy’s rose-tinted core. Some of these clumps of stars are notable — one of the most extreme Wolf–Rayet star clusters in the local Universe, NGC 3125-A1, resides within NGC 3125.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">Despite their appearance, the fuzzy white blobs dotted around the edge of this galaxy are not stars, but globular clusters. Found within a galaxy’s halo, globular clusters are ancient collections of hundreds of thousands of stars. They orbit around galactic centres like satellites — the Milky Way, for example, hosts over 150 of them.</div><br />Image Credit: ESA/Hubble & NASA, Judy Schmidt<br />Explanation from: https://www.spacetelescope.org/images/potw1629a/

The NGC 3125 Galaxy

This NASA/ESA Hubble Space Telescope image reveals the vibrant core of the galaxy NGC 3125. Discovered by John Herschel in 1835, NGC 3125 is...

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Evolution, Evolutionary history of Life on Earth and Geologic Time Scale

<div style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhyOcrZnyQDaLnQFXJGAkrrsol7wuGgWx78Esd5__By9pfWGJrzGbroqzIBQOfF-ntcV_eXh07ywrtgPyZQSASYtzT9wmIyZOpMRILJ7dHGFcRxekAhx6NZhL-YF6mJacg-cSOd1DW8mJ2d/s1600/Evolution.png" imageanchor="1"><img alt="Evolution, Evolutionary history of Life on Earth and Geologic Time Scale" border="0" height="566" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhyOcrZnyQDaLnQFXJGAkrrsol7wuGgWx78Esd5__By9pfWGJrzGbroqzIBQOfF-ntcV_eXh07ywrtgPyZQSASYtzT9wmIyZOpMRILJ7dHGFcRxekAhx6NZhL-YF6mJacg-cSOd1DW8mJ2d/s640/Evolution.png" title="" width="640" /></a></div><div style="text-align: center;"><br /></div><div style="text-align: center;"><span style="font-family: "georgia" , "times new roman" , serif; font-size: x-large;">Evolution</span></div><div style="text-align: center;"><br /></div><div style="text-align: center;">Evolution is change in the heritable characteristics of biological populations over successive generations. Evolutionary processes give rise to biodiversity at every level of biological organisation, including the levels of species, individual organisms, and molecules.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">All life on Earth shares a common ancestor known as the last universal common ancestor (LUCA), which lived approximately 3.5–3.8 billion years ago, although a study in 2015 found "remains of biotic life" from 4.1 billion years ago in ancient rocks in Western Australia. In July 2016, scientists reported identifying a set of 355 genes from the LUCA of all organisms living on Earth.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">Repeated formation of new species (speciation), change within species (anagenesis), and loss of species (extinction) throughout the evolutionary history of life on Earth are demonstrated by shared sets of morphological and biochemical traits, including shared DNA sequences. These shared traits are more similar among species that share a more recent common ancestor, and can be used to reconstruct a biological "tree of life" based on evolutionary relationships (phylogenetics), using both existing species and fossils. The fossil record includes a progression from early biogenic graphite, to microbial mat fossils, to fossilized multicellular organisms. Existing patterns of biodiversity have been shaped both by speciation and by extinction. More than 99 percent of all species that ever lived on Earth are estimated to be extinct. Estimates of Earth's current species range from 10 to 14 million, of which about 1.2 million have been documented. More recently, in May 2016, scientists reported that 1 trillion species are estimated to be on Earth currently with only one-thousandth of one percent described.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">In the mid-19th century, Charles Darwin formulated the scientific theory of evolution by natural selection, published in his book On the Origin of Species (1859). Evolution by natural selection is a process demonstrated by the observation that more offspring are produced than can possibly survive, along with three facts about populations: 1) traits vary among individuals with respect to morphology, physiology, and behaviour (phenotypic variation), 2) different traits confer different rates of survival and reproduction (differential fitness), and 3) traits can be passed from generation to generation (heritability of fitness). Thus, in successive generations members of a population are replaced by progeny of parents better adapted to survive and reproduce in the biophysical environment in which natural selection takes place. This teleonomy is the quality whereby the process of natural selection creates and preserves traits that are seemingly fitted for the functional roles they perform. Natural selection, including sexual selection, is the only known cause of adaptation but not the only known cause of evolution. Other, nonadaptive evolutionary processes include mutation, genetic drift and gene migration.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">In the early 20th century the modern evolutionary synthesis integrated classical genetics with Darwin's theory of evolution by natural selection through the discipline of population genetics. The importance of natural selection as a cause of evolution was accepted into other branches of biology. Moreover, previously held notions about evolution, such as orthogenesis, evolutionism, and other beliefs about innate "progress" within the largest-scale trends in evolution, became obsolete scientific theories. Scientists continue to study various aspects of evolutionary biology by forming and testing hypotheses, constructing mathematical models of theoretical biology and biological theories, using observational data, and performing experiments in both the field and the laboratory.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">In terms of practical application, an understanding of evolution has been instrumental to developments in numerous scientific and industrial fields, including agriculture, human and veterinary medicine, and the life sciences in general. Discoveries in evolutionary biology have made a significant impact not just in the traditional branches of biology but also in other academic disciplines, including biological anthropology, and evolutionary psychology. Evolutionary computation, a sub-field of artificial intelligence, involves the application of Darwinian principles to problems in computer science.</div><div style="text-align: center;"><br /></div><div style="text-align: center;"><br /></div><div style="text-align: center;"><span style="font-family: "georgia" , "times new roman" , serif; font-size: x-large;">Evolutionary history of Life on Earth</span></div><div style="text-align: center;"><br /></div><div style="text-align: center;">The evolutionary history of life on Earth traces the processes by which living and fossil organisms have evolved since life appeared on the planet, until the present day. Earth formed about 4.5 Ga (billion years) ago and there is evidence that life appeared within 0.5 billion years. The similarities between all present-day organisms indicate the presence of a common ancestor from which all known species have diverged through the process of evolution. More than 99 percent of all species, amounting to over five billion species, that ever lived on Earth are estimated to be extinct. Estimates on the number of Earth's current species range from 10 million to 14 million, of which about 1.2 million have been documented and over 86 percent have not yet been described.</div><div style="text-align: center;"><br /></div><div style="text-align: center;"><br /></div><div style="text-align: center;"><span style="font-family: "georgia" , "times new roman" , serif; font-size: x-large;">Geologic Time Scale</span></div><div style="text-align: center;"><br /></div><div style="text-align: center;">The geological time scale (GTS) is a system of chronological dating that relates geological strata (stratigraphy) to time, and is used by geologists, paleontologists, and other Earth scientists to describe the timing and relationships of events that have occurred during Earth’s history. The table of geologic time spans, presented here, agrees with the nomenclature, dates and standard color codes set forth by the International Commission on Stratigraphy.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">Evidence from radiometric dating indicates that Earth is about 4.54 billion years old. The geology or deep time of Earth’s past has been organized into various units according to events which took place in each period. Different spans of time on the GTS are usually marked by changes in the composition of strata which correspond to those, and indicate major geological or paleontological events, such as mass extinctions. For example, the boundary between the Cretaceous period and the Paleogene period is defined by the Cretaceous–Paleogene extinction event, which marked the demise of the non-avian dinosaurs and many other groups of life. Older time spans, which predate the reliable fossil record (before the Proterozoic Eon), are defined by their absolute age.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">Some other planets and moons within the Solar System have sufficiently rigid structures to have preserved records of their own histories, for example, Venus, Mars and the Earth's Moon. Dominantly fluid planets, such as the gas giants, do not preserve their history in a comparable manner. Apart from the Late Heavy Bombardment, events on other planets probably had little direct influence on the Earth, and events on Earth had correspondingly little effect on those planets. Construction of a time scale that links the planets is, therefore, of only limited relevance to the Earth's time scale, except in the whole-solar-system context. The existence, timing, and terrestrial effects of the Late Heavy Bombardment is still debated.</div><br /><br />Image Credit: United States Geological Survey<br />Explanation from: https://en.wikipedia.org/wiki/Evolution and https://en.wikipedia.org/wiki/Evolutionary_history_of_life and https://en.wikipedia.org/wiki/Geologic_time_scale

Evolution, Evolutionary history of Life on Earth and Geologic Time Scale

Evolution Evolution is change in the heritable characteristics of biological populations over successive generations. Evolutionary processes...

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Moonrise seen from the International Space Station

<div style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjmx3wVeTXuvjPCSrshd2L3FaqxQ8Ucw-VueomelyVrZ5c72MkSz0-hjQG6T7oevgPERbAVH67gJoN9-PSZGSTulq9A2whxm2Khrc_BnT_I-QuAWBJxTrUtIMJZi7VIkxgNO8mfME6ri8vV/s1600/moonrise-iss-01.JPG" imageanchor="1"><img alt="Moonrise" border="0" height="213" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjmx3wVeTXuvjPCSrshd2L3FaqxQ8Ucw-VueomelyVrZ5c72MkSz0-hjQG6T7oevgPERbAVH67gJoN9-PSZGSTulq9A2whxm2Khrc_BnT_I-QuAWBJxTrUtIMJZi7VIkxgNO8mfME6ri8vV/s320/moonrise-iss-01.JPG" title="" width="320" /></a><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi8VUps_EgzTmdnrwvxbR7b4bsxmBfVSVQGZfFjlzMJzXJmjLnQEXn9v2htMb3AjqGSPo0RKEYVqI6bnEJAnbmYjUlz7ulkNE3zgEjk3oRX1Broh02fvJky9cjXbn2qb6qE8gzX2Io22Eir/s1600/moonrise-iss-02.JPG" imageanchor="1"><img alt="Moonrise ISS" border="0" height="213" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi8VUps_EgzTmdnrwvxbR7b4bsxmBfVSVQGZfFjlzMJzXJmjLnQEXn9v2htMb3AjqGSPo0RKEYVqI6bnEJAnbmYjUlz7ulkNE3zgEjk3oRX1Broh02fvJky9cjXbn2qb6qE8gzX2Io22Eir/s320/moonrise-iss-02.JPG" title="" width="320" /></a><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj6nSqHmFByhVSnrhM3bi51UbclV9BFnw2OmMNramLMcJKjmpCtY9vJF-WafcA7O0877-Nuvn4lHjygO-N5kuv6g9nlNr1EvTpykKAixfZl53AoXwq9dSNEbZAW2wTp2PIeSP3HTdr5NbWs/s1600/moonrise-iss-03.JPG" imageanchor="1"><img alt="Moon" border="0" height="213" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj6nSqHmFByhVSnrhM3bi51UbclV9BFnw2OmMNramLMcJKjmpCtY9vJF-WafcA7O0877-Nuvn4lHjygO-N5kuv6g9nlNr1EvTpykKAixfZl53AoXwq9dSNEbZAW2wTp2PIeSP3HTdr5NbWs/s320/moonrise-iss-03.JPG" title="" width="320" /></a><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh1Az-ccZ-hLlUZTWfgjhWYfIxs1o-ptAJgUUHuwb6LgfpEtZJu5Y9F2fiCWpqk6Q2jOKmbEJgZnYxQchQY84audxEE5-tVcDE68Eisy3X674avB_QMzRrN_AT0pdhNbbnx-AXBeYLYTrTv/s1600/moonrise-iss-04.JPG" imageanchor="1"><img alt="Moonrise" border="0" height="213" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh1Az-ccZ-hLlUZTWfgjhWYfIxs1o-ptAJgUUHuwb6LgfpEtZJu5Y9F2fiCWpqk6Q2jOKmbEJgZnYxQchQY84audxEE5-tVcDE68Eisy3X674avB_QMzRrN_AT0pdhNbbnx-AXBeYLYTrTv/s320/moonrise-iss-04.JPG" title="" width="320" /></a><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgTUn5mAw0tH85l-eV5Sy8X4vQHxRaFyLHJGcHAIEe1z41tljBD2PDJjLzOs-JCCG2cNziz_PJvEXLybnb9-0UhhodyYe90BvwH9utnZz7eQGP0-R70Troa189fYmm2UL6CGQLmpU2CSJtd/s1600/moonrise-iss-06.JPG" imageanchor="1"><img alt="Moonrise ISS" border="0" height="213" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgTUn5mAw0tH85l-eV5Sy8X4vQHxRaFyLHJGcHAIEe1z41tljBD2PDJjLzOs-JCCG2cNziz_PJvEXLybnb9-0UhhodyYe90BvwH9utnZz7eQGP0-R70Troa189fYmm2UL6CGQLmpU2CSJtd/s320/moonrise-iss-06.JPG" title="" width="320" /></a><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiLGHuMe87BamayFaq0vhaDTWuWA7K_z4U4lvSniR8JiKJQkKcXU2e3-0aejJ6uzG4zDFqj7SToPt0TojoMvHSCQ1UczrJBABsIflMMBUoRwkQmQ1-coL1s2mIlhSfKSU13Kl2WETgaW7jj/s1600/moonrise-iss-07.JPG" imageanchor="1"><img alt="Moon" border="0" height="213" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiLGHuMe87BamayFaq0vhaDTWuWA7K_z4U4lvSniR8JiKJQkKcXU2e3-0aejJ6uzG4zDFqj7SToPt0TojoMvHSCQ1UczrJBABsIflMMBUoRwkQmQ1-coL1s2mIlhSfKSU13Kl2WETgaW7jj/s320/moonrise-iss-07.JPG" title="" width="320" /></a><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgncsKo8KsJX7BaDS7zE8FloDXYFW7ndLt3edEt-ZRRO6rQuJo-qhkn1IVGrOssOhrxaxf0liUYUEpLQsU7_qf7aCWLrm_aZ6Lz87Q59uTJw77UsOahNSlKjNB8YIFD-jZJ5XYdOj4WrLAI/s1600/moonrise-iss-08.JPG" imageanchor="1"><img alt="Moonrise" border="0" height="213" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgncsKo8KsJX7BaDS7zE8FloDXYFW7ndLt3edEt-ZRRO6rQuJo-qhkn1IVGrOssOhrxaxf0liUYUEpLQsU7_qf7aCWLrm_aZ6Lz87Q59uTJw77UsOahNSlKjNB8YIFD-jZJ5XYdOj4WrLAI/s320/moonrise-iss-08.JPG" title="" width="320" /></a><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhTuDMZGpoczG6cD264uhYxl1ec647sBB4K5Wl-fpifJbaaMcsMJwnBFjz10akExzNTBASoVy3b50_vpkZ9fgiBEQFwB8b60l_HDNoP0xUTKBMaDB4UjPcDTOcPPN-JfBIpIJ8muFvQKgl8/s1600/moonrise-iss-09.JPG" imageanchor="1"><img alt="Moonrise ISS" border="0" height="213" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhTuDMZGpoczG6cD264uhYxl1ec647sBB4K5Wl-fpifJbaaMcsMJwnBFjz10akExzNTBASoVy3b50_vpkZ9fgiBEQFwB8b60l_HDNoP0xUTKBMaDB4UjPcDTOcPPN-JfBIpIJ8muFvQKgl8/s320/moonrise-iss-09.JPG" title="" width="320" /></a><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi2InYqihYoyYzQ4fw0rB4lwKVUkw-1iTEEJss0kRaVFsZXs5vuUQ2NiWpwtDEA1T6itL5oLD-1vB8DmPmkDkVF8WXjYr97N7iSUnVnB_PXR-imKJvZPOzQDggaNbZxqjN8ibkTka51JGrE/s1600/moonrise-iss-10.JPG" imageanchor="1"><img alt="Moonrise" border="0" height="213" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi2InYqihYoyYzQ4fw0rB4lwKVUkw-1iTEEJss0kRaVFsZXs5vuUQ2NiWpwtDEA1T6itL5oLD-1vB8DmPmkDkVF8WXjYr97N7iSUnVnB_PXR-imKJvZPOzQDggaNbZxqjN8ibkTka51JGrE/s320/moonrise-iss-10.JPG" title="" width="320" /></a><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi-6jqhRCpUSpOndLyeiWzuFdZpVywTtPYrfxT22Tda0t3fN_WUVez5zndbW6V-vKKHlwKHkkWi7PCvbrv1b3YcnQucrLOISInP3gH4j_Q8uNklqFhDn-36yXPxxpLbH8bgPIBeE0HtcW_v/s1600/moonrise-iss-11.JPG" imageanchor="1"><img alt="Moonrise" border="0" height="213" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi-6jqhRCpUSpOndLyeiWzuFdZpVywTtPYrfxT22Tda0t3fN_WUVez5zndbW6V-vKKHlwKHkkWi7PCvbrv1b3YcnQucrLOISInP3gH4j_Q8uNklqFhDn-36yXPxxpLbH8bgPIBeE0HtcW_v/s320/moonrise-iss-11.JPG" title="" width="320" /></a><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh-Xm7kyjRuod0B4GefDZcWc48x6GBk3SxrGLLH2MNcgOiLCHM_c4GzvOTdEwvlJFkBc2B8OHEqyFjoTLgpYYG10dgEfGDHzuveMWx7g7qZy1a8TwVl-yO5zN0lAFlB2ynF-Srdq2qje35U/s1600/moonrise-iss-12.JPG" imageanchor="1"><img alt="Moonrise ISS" border="0" height="213" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh-Xm7kyjRuod0B4GefDZcWc48x6GBk3SxrGLLH2MNcgOiLCHM_c4GzvOTdEwvlJFkBc2B8OHEqyFjoTLgpYYG10dgEfGDHzuveMWx7g7qZy1a8TwVl-yO5zN0lAFlB2ynF-Srdq2qje35U/s320/moonrise-iss-12.JPG" title="" width="320" /></a><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhky7hyphenhyphen06qQu6_fOClsXdCas8XbY1hFFJDTHUOR2bKOA2FT27yKcaX7YslYghAzmHtWdxvpPk0Bl7wJ12eDGSAoZWQvZtCcyrxvpRev887MT23ks-jHlq202We34n2K0Skbebix7IWZhyphenhyphenn5/s1600/moonrise-iss-13.JPG" imageanchor="1"><img alt="Moonrise" border="0" height="213" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhky7hyphenhyphen06qQu6_fOClsXdCas8XbY1hFFJDTHUOR2bKOA2FT27yKcaX7YslYghAzmHtWdxvpPk0Bl7wJ12eDGSAoZWQvZtCcyrxvpRev887MT23ks-jHlq202We34n2K0Skbebix7IWZhyphenhyphenn5/s320/moonrise-iss-13.JPG" title="" width="320" /></a></div><div style="text-align: center;"><br /></div><div style="text-align: center;">ISS, Orbit of the Earth</div><div style="text-align: center;">August 2016</div><br />Image Credit: NASA/ESA

Moonrise seen from the International Space Station

ISS, Orbit of the Earth August 2016 Image Credit: NASA/ESA

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Spiral Galaxy NGC 24

<div style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjqMPKgTK2DLPedqaqNWGZH6M_n1h9UVVsWKGjAnKGOLs_CbyDUq7sPyuu4gb0rUSDlEMCwMJvAP6HvfzR94z0zaN8UjSWtTHV0ya69ZxvQdigQ4vj8iNPAkhS-MwPoQDTKdaNBKPfzMXts/s1600/Spiral-Galaxy-NGC-24.jpg" imageanchor="1"><img alt="Spiral Galaxy NGC 24" border="0" height="640" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjqMPKgTK2DLPedqaqNWGZH6M_n1h9UVVsWKGjAnKGOLs_CbyDUq7sPyuu4gb0rUSDlEMCwMJvAP6HvfzR94z0zaN8UjSWtTHV0ya69ZxvQdigQ4vj8iNPAkhS-MwPoQDTKdaNBKPfzMXts/s640/Spiral-Galaxy-NGC-24.jpg" title="" width="623" /></a></div><div style="text-align: center;"><br /></div><div style="text-align: center;">This shining disc of a spiral galaxy sits approximately 25 million light-years away from Earth in the constellation of Sculptor. Named NGC 24, the galaxy was discovered by British astronomer William Herschel in 1785, and measures some 40 000 light-years across.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">This picture was taken using the NASA/ESA Hubble Space Telescope’s Advanced Camera for Surveys, known as ACS for short. It shows NGC 24 in detail, highlighting the blue bursts (young stars), dark lanes (cosmic dust), and red bubbles (hydrogen gas) of material peppered throughout the galaxy’s spiral arms. Numerous distant galaxies can also been seen hovering around NGC 24’s perimeter.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">However, there may be more to this picture than first meets the eye. Astronomers suspect that spiral galaxies like NGC 24 and the Milky Way are surrounded by, and contained within, extended haloes of dark matter. Dark matter is a mysterious substance that cannot be seen; instead, it reveals itself via its gravitational interactions with surrounding material. Its existence was originally proposed to explain why the outer parts of galaxies, including our own, rotate unexpectedly fast, but it is thought to also play an essential role in a galaxy’s formation and evolution. Most of NGC 24’s mass — a whopping 80% — is thought to be held within such a dark halo.</div><br />Image Credit: ESA/Hubble & NASA<br />Explanation from: https://www.spacetelescope.org/images/potw1639a/

Spiral Galaxy NGC 24

This shining disc of a spiral galaxy sits approximately 25 million light-years away from Earth in the constellation of Sculptor. Named NGC 2...

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Abiogenesis - Origins of Life on Earth

<div style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhf0HJ3xjl00wrcy7Bx5wiqWkjf3U17Ihyphenhyphenh_b0LYBmslFGC1drCAN_M-ejYjdYpCWSS86c3nT0sfzg3bgseGfbcp1lt6QYhdNTya3_oWhDe3wGUYQwynn9jW2Gx7GDgiJ79pXqKXxM7-21o/s1600/Abiogenesis-Origins-of-Life-on-Earth.jpg" imageanchor="1"><img alt="Abiogenesis - Origins of Life on Earth" border="0" height="420" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhf0HJ3xjl00wrcy7Bx5wiqWkjf3U17Ihyphenhyphenh_b0LYBmslFGC1drCAN_M-ejYjdYpCWSS86c3nT0sfzg3bgseGfbcp1lt6QYhdNTya3_oWhDe3wGUYQwynn9jW2Gx7GDgiJ79pXqKXxM7-21o/s640/Abiogenesis-Origins-of-Life-on-Earth.jpg" title="" width="640" /></a></div><div style="text-align: center;"><br /></div><div style="text-align: center;">Abiogenesis or biopoiesis or OoL (Origins of Life), is the natural process of life arising from non-living matter, such as simple organic compounds. It is thought to have occurred on Earth between 3.8 and 4.1 billion years ago. Abiogenesis is studied through a combination of laboratory experiments and extrapolation from the characteristics of modern organisms, and aims to determine how pre-life chemical reactions gave rise to life on Earth.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">The study of abiogenesis involves geophysical, chemical, and biological considerations, with more recent approaches attempting a synthesis of all three. Many approaches investigate how self-replicating molecules, or their components, came into existence. It is generally thought that current life on Earth is descended from an RNA world, although RNA-based life may not have been the first life to have existed. The classic Miller–Urey experiment and similar research demonstrated that most amino acids, the basic chemical constituents of the proteins used in all living organisms, can be synthesized from inorganic compounds under conditions intended to replicate those of the early Earth. Various external sources of energy that may have triggered these reactions have been proposed, including lightning and radiation. Other approaches ("metabolism-first" hypotheses) focus on understanding how catalysis in chemical systems on the early Earth might have provided the precursor molecules necessary for self-replication. Complex organic molecules have been found in the Solar System and in interstellar space, and these molecules may have provided starting material for the development of life on Earth.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">The panspermia hypothesis alternatively suggests that microscopic life was distributed to the early Earth by meteoroids, asteroids and other small Solar System bodies and that life may exist throughout the Universe. It is speculated that the biochemistry of life may have begun shortly after the Big Bang, 13.8 billion years ago, during a habitable epoch when the age of the universe was only 10 to 17 million years. The panspermia hypothesis therefore answers questions of where, not how, life came to be; it only postulates that life may have originated in a locale outside the Earth.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">Nonetheless, Earth remains the only place in the Universe known to harbour life, and fossil evidence from the Earth supplies most studies of abiogenesis. The age of the Earth is about 4.54 billion years; the earliest undisputed evidence of life on Earth dates from at least 3.5 billion years ago, and possibly as early as the Eoarchean Era, after a geological crust started to solidify following the earlier molten Hadean Eon. Microbial mat fossils have been found in 3.48 billion-year-old sandstone in Western Australia. Other early physical evidence of biogenic substances includes graphite and possibly stromatolites discovered in 3.7 billion-year-old metasedimentary rocks in southwestern Greenland, as well as "remains of biotic life" found in 4.1 billion-year-old rocks in Western Australia. According to a scientist who commented on the study, "If life arose relatively quickly on Earth … then it could be common in the universe."</div><br />Explanation from: https://en.wikipedia.org/wiki/Abiogenesis

Abiogenesis - Origins of Life on Earth

Abiogenesis or biopoiesis or OoL (Origins of Life), is the natural process of life arising from non-living matter, such as simple organic co...

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Sunset seen from the International Space Station

<div style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhljwFluVvWEnzXVHbTJ-K_alsOosPY58zQTqLOabjaQfmDq68lpaTr5IpXd0FhPN9JFkXVcWzqU69wAlDXZ7uyiC08bqoei4Xfwb57eUlHE0VjYXuaIBJbqAvgGBO8X5ZuH81JLlGAeKg8/s1600/Sunset-ISS.JPG" imageanchor="1"><img alt="Sunset seen from the International Space Station" border="0" height="426" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhljwFluVvWEnzXVHbTJ-K_alsOosPY58zQTqLOabjaQfmDq68lpaTr5IpXd0FhPN9JFkXVcWzqU69wAlDXZ7uyiC08bqoei4Xfwb57eUlHE0VjYXuaIBJbqAvgGBO8X5ZuH81JLlGAeKg8/s640/Sunset-ISS.JPG" title="" width="640" /></a></div><div style="text-align: center;"><br /></div><div style="text-align: center;">ISS, Orbit of the Earth</div><div style="text-align: center;">August 2016</div><br />Image Credit: NASA/ESA

Sunset seen from the International Space Station

ISS, Orbit of the Earth August 2016 Image Credit: NASA/ESA

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Reflection Nebula BFS 29

<div style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj5OHPMyMjKkMH1DL_jV2EGe7iNvHNoVMvyzZMQi1bXNewL89DF_YcsV8FGrglqqo9i01suhh-zge4U4Zo_2xPRY0phXHqcACMjKUIDCPVYFgqPTd581h2vLjgtAxQSUcAA41XcqEFeU9b9/s1600/Reflection-Nebula-BFS-29.jpg" imageanchor="1"><img alt="Reflection Nebula BFS 29" border="0" height="506" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj5OHPMyMjKkMH1DL_jV2EGe7iNvHNoVMvyzZMQi1bXNewL89DF_YcsV8FGrglqqo9i01suhh-zge4U4Zo_2xPRY0phXHqcACMjKUIDCPVYFgqPTd581h2vLjgtAxQSUcAA41XcqEFeU9b9/s640/Reflection-Nebula-BFS-29.jpg" title="" width="640" /></a></div><div style="text-align: center;"><br /></div><div style="text-align: center;">NASA's Wide-field Infrared Survey Explorer, or WISE, captured this colorful image of the nebula BFS 29 surrounding the star CE-Camelopardalis, found hovering in the band of the night sky comprising the Milky Way. Most of the gas and dust in this image cannot be seen directly in visible light, but WISE's detectors revealed exquisite new details, and even some hidden stars.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">The nebulous interstellar gas and dust in this image is known as BFS 29. "BFS" stands for Blitz, Fich, and Stark -- the three astronomers who identified and catalogued 65 new star-forming regions in 1982 (the "29" simply means that it's the 29th object in their catalog). In visible light, BFS 29 can be seen, but only very slightly. This is because the dust scatters and reflects some of the light from nearby stars, hence its classification as a reflection nebula. The gas in BFS 29 also contains large amounts of ionized hydrogen -- referred to by astronomers as "H II." Hence, the nebula is also classified as an HII region. Reflection nebulae and HII regions are often associated with star formation.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">Most of the illumination and energy in BFS 29 is likely provided by the star CE-Camelopardalis. The "CE" in its name comes from a complex naming system for variable stars. Camelopardalis is the name of the constellation in which it is found, and means giraffe in Latin (from a camel wearing a leopard's coat). Of the three brightest stars in this image, it is the bright pink-colored star nearest to the center of the image. The other two bright stars cannot be seen in visible light; they are hidden behind the clouds of gas and dust. In infrared light, however, they shine through brilliantly. CE-Camelopardalis is a variable supergiant star, which means it will eventually end its life in a supernova, likely leaving behind a black hole. It is near the giraffe's hind foot, making a sort of ankle bracelet, as compared to the emerald necklace featured in the Nov. 9, 2010 image.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">All four of WISE's infrared detectors were used to make this image. The colors used represent specific wavelengths of infrared radiation. Blue and blue-green (cyan) represent 3.4- and 4.6-micron light, respectively. These wavelengths are mainly emitted by stars within the Milky Way. Green represents 12-micron light, which is emitted by the warm gas of the nebulae. Red represents the longest wavelength, 22-micron light emitted by cooler dust within the nebulae.</div><br />Image Credit: NASA/JPL-Caltech/UCLA<br />Explanation from: http://photojournal.jpl.nasa.gov/catalog/PIA13459

Reflection Nebula BFS 29

NASA's Wide-field Infrared Survey Explorer, or WISE, captured this colorful image of the nebula BFS 29 surrounding the star CE-Camelopar...

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