1. The total lifetime of the Sun is close to 10 billion years. Estimate the lifetime of a star three times as massive as the Sun, and explain why it is likely or unlikely for complex, multi-cellular...

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    1. The total lifetime of the Sun is close to 10 billion years. Estimate the lifetime of a star three times as massive as the Sun, and explain why it is likely or unlikely for complex, multi-cellular life to be able to evolve on a planet in the habitable zone around that star.
    “Cycle / second limits evolve through the stellar post MS, each in an effective stellar flux at the height of the planet's atmosphere, additionally as an orbital distance from the star because of the dynamic SED of the star's property and physical property, several times. we tend to derive a parameterization to encrypt the post-main sequence “The HZ distances to grid stars old enough to be currently in the post-main sequence mistreatment (Sun - A5) the constants provided in the table Our parameterization includes only the dynamic portion of RGB, over most planets it retains its atmospheres wherever D is the distance (in AU) and t is stellar age for star metallic stars (in Gyr). The effective stellar flow at the limits of the post-MS-HZ discussed in the diagram decreases across the RGB by ~ 22% for F1 and five hitter in the M1 stellar type. These two stellar types support the maximum and minimum modification of physical property for our grid of stars in several ways. The correspondent will increase over the helium flash and reduce over the subsequent AGB, several times, the area unit forty-two and sixty-nine for the M1 and eight for the stellar type F1. Note that the time scales of stellar evolution differ for the various stars. The orbital distance of the post-MS-HZ limits changes with time. The internal associate at the outer edges of the Tending of the post-MS / second cycles for an A5 star is initially fixed at three and seven AU, at the beginning of RGB, before moving to twenty-eight and seventy-two AU at the top. RGB (total duration: ~ fifty Myr). when argon flashes, the unit area of the inner and outer edges is at half a dozen and fourteen AU, several times at the beginning of the AGB, extending to seventy-two and 192 AU across the top of the AGB (total duration: ~ 183Myr) . As internal and external edges of our Sun post MS unit cycles / second area are recorded for the first time in the first.3 and 3.3 AU before increasing to a few and six and 123 AU over the top of the RGB (total duration: ~ 850 Myr). Throughout the AGB, the post-MS / second cycles are moved to five and three AU for thirty-nine and ten and ten AU, in a variable manner (total duration: ~ one hundred and sixty Myr). the post-MS / unit area cycles of the second parts in the first configuration at zero.3 and 0.9 AU and double increase in thirteen and thirty-four AU by the upper part of RGB (total duration: ~ nine Gyr). Second, it is not necessary for all times to evolve over the post-MS part. Life could have started in the Nursing Associate in the first habitable atmosphere (for example, throughout the pre-MS part of the star, so as to be a captive surface surface, or remain asleep until the surface conditions allow it to move towards planet surface again, as in stars excessively «post-EM part.”(Бонев and Александров, 1993)
D= at4 +bt3 +ct2 +dt +e
    
    2. What were the factors that may have contributed to the remarkable explosion of diversity and functionality during the Cambrian Era? Why did this happen only in the Cambrian period, some 3 billion plus years after life first arose on the planet? That is, why did it take so long?
    “The Cambrian Explosion can be a development that encompasses the dramatic appearance of various metazoans with bi-mineralized skeletons, an increase in the complexity and behavior of animals, a revolution of substrates that organized the registration of matter and also the development of marine biodiversity ecosystems with complicated food networks.The relative importance of external factors, such as the increase in the element or the chemistry of salt water changes6–9, biological factors, such as the influence of animal irrigation and feedbacks between the two, are still unclear. Likewise, the connection between the Ediacaran and Cambrian biotas remains unsolved, with some arguments that the Cambrian explosion includes a 'deep root' within the Ediacaran terminal or that the main part of the 'Cambrian explosion' was the assembly of Nama (~ 550– 541 Ma), or appeared even earlier on the Avalon-White ocean boundary at ~ 561 Ma14. In addition, although it has been conjectured that metazoan extinction or turnover events occurred at ~ 551 Ma13.15 and at the Ediacaran / Cambrian border at ~ 541 - 540 Ma there is no agreement on the precise type of these dynamics, that is, their temporal order, or causes the duration of the beginning of the Cambrians to the Siberian Platform in Russia, with important radiometric dates (numbered; radiometric dates from Siberia are in bold), international chronostratigraphy (ICS) and stages and zones accepted by the Siberian Platform. Radiometric dates of 127.93; 294; 395, 496; 597; 698–100; 730; 8101 The right column shows numbered time units, each c. 2.5 Myr in length. dysfunction = Ediacaran. three = Cambrian Series three, pars. Changed.”(Zhuravlev and Wood, 2018)
    
    3. Why have most SETI searches been carried out at radio wavelengths?
     “Research by Extraterrestrial Intelligence (SETI) on radio frequencies concentrated - historically on normal slowly astronomical modulated band signals. The assumption of activating the Nursing Associate is that each of the robust radio sources (> 1Jy) is already being used by astronomers with a natural origin. The statement is not fully supported by existing exhibitions. Some robust radio sources may display a message hidden, disguised, or hitchhiking, a robust natural supply. While several different pulses and sources can be tested for repetitive power modulation, the authors do not appear to be alert to previous work tests for codings that use, for example, constant power modulation from displayed sources. The last is the focus here. Suppose the ET builds strong information about the cause, transmitting a small rate between 103 and 109 cycles per second. For most radio telescopes, this transmitter is indistinguishable from a natural time supply as a result of square time fluctuations, too small to be seen in normal detectors. However, these same signals can be detectable by the car, correlating an amplitude and a section of the electric field, also called field autocorrelation detection (FAC). Here, we have a tendency to present or what we believe to be the main radio exploration for detecting advanced signals for abuse in the TSI.
Hypothesis1. The electric fields emitted from the many robust radio sources previously discovered with flow> 1 Jy of square measure modulated with a continuation pattern directly by extraterrestrials or thanks to some physics still unknown.
.Hypothesis2. Many exoplanets emit artificial signals of moderate bandwidth (for example, one MHz) that were not verified in time surveys or in initiated ETI band searches. If these signals contain repetitive structure, they will be detected by autocorrelation.”(Harp et al., 2018)
    
     4. What is a stromatolite, and why is it important for our understanding of the evolution of life on Earth?
    “Stromatolytes normally found in carbonaceous sequences of the aeon are one of the evidences of aeon life. they are varied, found in abundance, and sometimes graphics associated with them produce microscopic fossils. These microfossils are an excellent supply of our information about childhood. Stromatolites have been used together in biostratigraphy. In India, structures similar to those currently considered stromatolites were observed by McClelland in the early 19th century (1834, registered as ring characteristics). As a peculiar isolated and laminated sedimentary rock, while W. H. Auden documented and recorded these structures in the Vindhyan Basin only as ellipsoidal bodies. No systematic study was carried out until the 1960s. Investigations in the late 1960s uncovered records of deep stromatolite occurrences within the Asian country's eon rocks. LED continued research for stromatolite discoveries, even in younger Gondwana sediments from the marginal Talchir Maritime Formation later inferred to be of H2O origin. Despite the profound occurrences of stromatolytic structures in the Asian nation and together in alternative elements of the planet, efforts were not made to verify them consistently in the middle of the 20th century. the purpose of this article is to trace the studies of stromatolites in the Asian nation and the way the Indian team qualified the developments that take place in the field of stromatolite studies in alternative elements of the planet. It jointly summarizes Indian contributions during this field of study. Despite the various aspects of studies in the past,stromatolites, even at the moment, are the maximum enigmatic quantity they were not at the beginning of part of the last century. in his book "stromatolites", comment that Kalkowasky "coined and outlined a stromatological word; however, there is a growing concern and concern about its use., nature (biogenic / a biogenic), formation (addition / production), abortive organisms ( bacteria / cyanobacteria; prokaryotes / eukaryotes), permanent (general fossil / fossil index), biostratigraphic potential (mileage), classification (binomial phytological system / sediment / geometric nomenclature) and economic importance (primary / secondary improvement), commercial performance indicator (rods / real / proxy) etc., far from solution. Earth's history is involved in hypotheses, exhibitions and awards. Understanding the Sun-Earth-Moon, as well as in the Earth's rotation. earth science ages.”(Sharma, 2008)
    
    5. What is a “hot Jupiter”? How do hot Jupiters violate the expectations that we might have for Jovian planets, based on the nebular hypothesis for the formation of the solar system? How might we preserve the nebular hypothesis and still be able to explain hot Jupiters?
    “Since the primary traffic detections of the Tending Associate extra solar planet, the nearby large extra solar planet, or hot Jupiter, the population has shown itself to be enigmatic. it had been recognized early that many of these hot Jupiter’s had radii greater than expected in the usual models, considering only the cooling of an initial state of high entropy (for reviews, the main traffic detections of the extra solar planet Associate in Nursing, the nearby extra solar planet The population of a large planet, or "hot Jupiter", proved to be enigmatic, it was recognized from the beginning that many of these hot Jupiter’s have radii greater than expected in the usual models, considering only the cooling from of a high entropy initial state. radius diagram of the hot-Jupiter sample is shown in the figure with cooling models presumed variable amounts of stellar incident over-plotted.”(Komacek and Youdin, 2017)
    
     6. What is a “super-Earth” and in what ways might it present a more challenging environment for complex life to subsist than the Earth. Are there any ways in which a super-Earth might be a better habitat than the Earth?
    “A substantial amount of analysis is conducted and resources are spent to search for planets that could be habitats for greater stellar life. Engineers and astronomers developed expensive instruments and huge ground-based telescopes, such as the HARPS (High Precision Speed Spectrograph) on the 3.6 m ESO telescope, and therefore the Spectrograph Echelle Ultraviolet-Visual Echelle (UVES) on the terribly massive telescope (VLT) , and launched the domestic telescopes of painters and uranologists with the specific objective of perceiving and characterizing Earth-sized planets. Even bigger facilities are being planned or built, like the extraordinarily massive ecu Telescope (E-ELT) and therefore James Webb's Telescope house (JWST), associated that a growing community of scientists is operating to unravel not just the empirical, but in addition to the theoretical and laboratory challenges. On the theoretical front, the stellar habitable zone (HZ) design has been widely used to determine habitable planets without a doubt. To the confusion of some, planets that reside at intervals of one star cycle per second are generally called habitable planets. However, a planet within the cycle per second does not need to be habitable in the sense that there are at least some niches that leave the existence of liquid surface water. Naturally, since the Earth is the only populated world that we all know, this object is sometimes a reference for studies on habitability.” (Fowler, 2019)
    
    7. Can interstellar travel be seriously considered as a viable solution to overpopulation on the Earth? Why or why not? What might be other, reasonable motives to undertake interstellar travel?
    “The instruments are being designed a lot thanks to the discovery and characterization of Earth-like planets and spectroscopic signatures of life in Earth-like atmospheres. However, alternative worlds offer conditions that are very suitable for all times to emerge and evolve. In addition to the planets, the moons may well be habitable, to search for a habitable ultimately associated with an established world, a conception of characterization that is bio central rather than geo or partial is necessary. Many reliable international thermostats, which prevent states associated with the ice ages, would prevent an existing scheme from undergoing mass extinctions, which can slow or frustrate devolution. There should be part and processes of earth sciences whose interaction constitutes a thermostat that creates a super habitable planet. Triggered by recent discoveries of super-terrestrial planets in or near stellar Hertz, mechanisms for using atmospheric CO2 and CH4 are designed for probably water-rich planets. freezes and although it does not have direct contact with the rocky interior. In these worlds, the associated Earth-like carbon silicate cycle is unlikely to operate, as there would be no weathering with carbon dioxide. As an alternative, networks of aggressive water molecules can attract carbon dioxide gas as guest molecules, a chemical known as carbon clathrate and provide a good environmental condition thermostat, moderating the levels of H2O and carbon dioxide gas in super- water-rich land. . similar clathrate mediation was achievable for CH4 instead of carbon dioxide that is, alkane series clathrate. Clathrate convection may well be a good mechanism for moving CH4 and / or carbonic acid gas from the iron-silicate core of a water-rich planet through an aggressive ice sheet in the ocean and, finally, into the atmosphere.”(Fowler, 2019)
    
    8. What are the underlying assumptions of the “Fermi Paradox”?
    “To debate Fermi's contradiction, a minimum of one definition must agree: sometimes it is life, intelligence or civilization. However, creating distinctions between these ideas could, in itself, associate unjustified assumptions. A system is taken into account alive if it decreases or maintains its internal entropy, increasing the entropy of its surroundings. A system is considered intelligent if its actions aim to maximize its future freedom of action. A living system aims to attenuate the dispersion of its detected states, while victimizing these sensations to infer external states of the planet. The three definitions above the square measure the equivalent on scales relevant to Fermi's contradiction. Proof: Initial, allow us to take into account a system that maximizes your future freedom of action. once given a set of alternative methods, this system can select the track that maximizes an average of short-term directions, weighted by the variety of long-term methods that they create accessible. However, accurate integration on semi-permanent methods needs complete data on all factors that are likely to affect the system, that is, zero dispersion of the detected states. as dispersion will increase, the accuracy of path integration will only decrease. Therefore, as of the Second, maintaining or decreasing the interior entropy of a system needs a continuous increase in its external entropy. Therefore, the system ceases to live when its energy reservoir runs out or seeks additional energy within the external environment. And, as any action will increase entropy, seeking additional energy long enough is to love maximizing future freedom of action. Therefore, follows from a pair of. the semi-permanent average of surprise (also known as "free energy") is entropy ", wherever" periodicity implies that the average time of any measurable system operation converges (almost certainly) over a sufficient amount of time ". Considering the time scales relevant to Fermi's contradiction, we tend to conclude that a pair of 1 follows a pair of 3. An agent is an associated entity that complies with any of the equivalent definitions and A is the set of all agents potential. Civilization is then described as an associated whimsical non-empty set of A.”(Berezin, 2019)
    
    9. If the Galilean satellites of Jupiter always keep the same face pointed toward Jupiter because they are tidally “locked on” to Jupiter, how can they be heated by tidal friction?
    “However, now there is a game changer: after years of timid insinuations, NASA is, for the first time, seriously planning to send humans to Mars after 2030 (First Landing Site/Exploration Zone Workshop for Human Missions to the Surface of Mars, 2015; Obama, 2016; National Aeronautics and Space Administration Transition Authorization Act, 2017), including chartering a previous planning study to support Mars water in situ resource utilization for eventual human missions (ME- PAG, 2016). In addition, given the rapid advances in space flight technologies by other national space programs as well as within the private sector, it is not out of the realm of possibilities that other stakeholders may precede NASA in completing human missions to Mars and the moment that an astronaut sets foot on Mars, Planetary Protection policies as we conceive them today will no longer be valid as microbial contamination from the human visitors will be unavoidable humans will increase not only the number (a human being is a collection of roughly 70 trillions of cells and bacteria; however, microbial invasion is not simply a matter of numbers) but also most importantly the diversity of microorganisms flying to Mars”(Fairén et al., 2017)
    
    10. What are the advantages of liquid water over other possible liquids as a medium in which life might have arisen?
    “Water is the most abundant liquid on Earth and, together, the substance with the greatest variety of anomalies in its properties. it is a requirement to maintain and intrinsically an almost vital subject of current analysis in chemical and chemical physics. Despite its simplicity as a liquid, it is an incredibly rich section diagram in which different types of ice cream, amorphous phases and anomalies reveal a path that points to physical science distinct from its supercooled liquid state that also hides several undisclosed secrets . are designed to clarify the abnormal properties that increase powerfully within the supercooled region. Among them, the second critical state of affairs has been investigated extensively and, at this point, most experimental evidence experiences the current state of affairs. ranging from terribly low temperatures, an existence line between a high density amorphous section and a low density amorphous section would continue on a very close existence line between a high density and low density liquid section, ending at a liquid-liquid junction , LLCP. When approaching this LLCP from the region of a phase, an intersection is found in the science and dynamics of physics. this is often mentioned, supporting an image of a temperature-dependent equilibrium between a high-density liquid and a low-density liquid, favored by various entropy and total heat, resulting in the same image as the physical science of bulk water. The nucleation of ice is mentioned further, as this is often what severely impedes experimental investigation of the planned LLCP neighborhood..”(Gallo et al., 2016)
    
    11. What lines of strong evidence led investigators to conclude that the KT extinction occurring 65 million years ago was caused by the impact of a large body, perhaps an asteroid, 10 – 15 km in diameter? How do we know that this event occurred exactly 65 million years ago?
    “To be habitable, a world (planet or moon) cannot be placed within the stellar habitable zone (HZ), and the worlds within the cycle do not appear to be essentially habitable. Here, we tend to illustrate, however, the recurrent warming of events will make terrestrial or icy worlds on the other side of the stellar cycle habitable. Scientists have developed language that neglects the potential existence of worlds that provide life with many more benign environments than Earth. We tend to decide these objects as super-habitable and discuss in which contexts this term can be used, that is, that the worlds tend to be much more habitable than the Earth. In the appendix Associate in Nursing, we tend to show why the principle of mediocracy does not usually logically justify why the Earth should be a very habitable planet or why different haunted worlds should look like the Earth. Super habitable worlds must be thought of for future observations of accompanying signs of extraterrestrial life. Considering a variety of physical effects, we tend to conclude that they tend to be a little older and much larger than Earth, where their host stars are possibly K dwarfs.”(Heller and Armstrong, 2014)
    
    12. How is RNA different from DNA and how is it similar? What is the usual role of RNA? … of DNA? What are some of the reasons why many scientists think
that life may have started with RNA as the carrier of genetic information, rather than DNA?
    “Deoxyribonucleic acid or DNA is the hereditary material of most of the organisms. A majority of DNA is located in either the nucleus or nucleoid. Some may remain inside mitochondria and chloroplast as well. DNA carries the genetic Sugar phosphate backbone in DNA is formed by nitrogenous bases and phosphate groups attached to the sugar deoxyribose. CH bonds in deoxyribose sugar are less reactive. Therefore, DNA is considerably stable in alkaline conditions. Four different nitrogenous bases can be identified in DNA: cytosine (C), guanine (G), adenine (A) and thymine (T). The two polynucleotide strands are held together by hydrogen bonds, forming between complement bases. Adenine (A) pairs with thymine (T) whereas cytosine (C) pairs with guanine (G). Thus, each strand is complementary. The two polynucleotide strands are further coiled to form a double helix. “Each strand in the double helix run in opposite directions, making the two strands antiparallel. The asymmetric ends of the strand are identified as 5′ and the 3′ ends. Major groove (22 Å wide) and minor groove (12 Å wide) can be found within the double helix.B form is the most common conformation of DNA within all organisms. The order which the four bases are arranged along the backbone encodes biological information within DNA stretches called genes. DNA synthesizes an identical copy of the original DNA, for reproduction. DNA can be easily damaged by ultraviolet light Ribonucleic acid or RNA is mostly found in the cytoplasm. Some may be also found in the nucleus. Many viruses store their genetic information in RNA genomes. RNA has a vital role in the regulation and expression of genes. RNA is a polynucleotide composed of nucleotide monomers same as DNA. RNA has a much shorter strand compared to DNA. Ribose is the sugar which forms the sugarphosphate backbone. Ribose is much reactive due to the hydroxyl group at 2′ position of the pentose ring. Therefore, RNA is not stable in alkaline conditions. Due to the presence of 2′OH group, RNA exists in Aform. Aform geometry generates a deep, narrow major groove and a shallow, wide minor groove. The four nitrogenous bases found in RNA are cytosine (C), guanine (G), adenine (A) and uracil (U). Unlike DNA, RNA exists as a single Stranded molecule most of the times but it can form double Stranded secondary structures such as hairpin loops by complementary base pairing; Adenine (A) pairs with uracil (U) whereas cytosine (C) pairs with guanine (G).” (Panawala, 2017)
    
    13.If intelligence has obvious survival advantages for a species, why didn’t it emerge more quickly during the course of evolution? What are some of the costs of advanced intelligence?
    “Behavior and characteristics learned in the extension of people affected considerably the evolution in the extension of species. Baldwin's impact on applications as individual responses to processes can damage targeted, non-random processes. Open comments from prominent peers postures conflict completely differently in relation to Baldwin's impact and definition. The operational definition of Baldwin's impact used this article: malleability can be a positive impact on evolution that affects the pressure of choice. This “permanent genetic variation is often chosen so that evolution proceeds in the direction of the induced plastic response. According to this definition, or Baldwin's impact describes an evolution of the target genotypic attribute that corresponds to the plastic response induced by the environment at the composition level. In other words, an induced plastic response determines a direction in which the genotype evolves. This definition is particularly relevant when considering biologically galvanized optimization techniques. Plasticity is understood to influence the speed with which evolution converges to some "target" configuration. This work, in distinction, addresses the question of whether or not malleability during an alternately alternative scenario will cause the evolution of several genetic characteristics of the existence of Baldwin's result during a cyclical scenario and will determine the novel "Baldwin's deviation effect", that is, an attribute (generalist configuration) evolves as a result of malleability that does not correspond to the plastic response evoked by a configuration that changes cyclically (specialized configuration) and also by the conditions under which it exists. A mathematical model verifies that the introduction of malleability in the composition alters the scenario of physical conditioning in a way that the configuration of the Renaissance man becomes the world ideal in the area of ​​genotypes. These results are relevant to the literature on the biological process Biology, as they expand the understanding of how phenotypic malleability influences evolution and presents a completely unique result caused by the interaction between learning and evolution. These results can also facilitate knowledge of the result of a rapid learning method in a slow learning method in another context, which includes an alternative element, for example, forming opinions in contexts where learning mediates speed from exposure to completely different. opinions”(Id, Bennati and Helbing, 2019)
    
    14. What are the three branches on the tree of life, and which branch are we on? What characteristics differentiate the organisms on our branch from the others?
    “Early approaches to describe the tree of life distinguished organisms based on their physical characteristics and metabolic features. Molecular methods dramatically broadened the diversity that could be included in the tree because they circumvented the need for direct observation and experimentation by relying on sequenced genes as markers for lineages. Gene surveys, typically using the small subunit ribosomal RNA (SSU RNA) gene, provided a remarkable and novel view of the biological world but questions about the structure and extent of diversity remain. Organisms from novel lineages have eluded surveys, because many are invisible to these methods due to sequence divergence relative to the primers commonly used for gene amplification. Furthermore, unusual sequences, including those with unexpected insertions, may be discarded as artefacts. The tree of life as we know it has dramatically expanded due to new genomic sampling of previously enigmatic or unknown microbial lineages. This depiction of the tree captures the current genomic sampling of life, illustrating the progress that has been made in the last two decades following the first published genome. What emerges from analysis of this tree is the depth of evolutionary history that is contained within the Bacteria, in part due to the CPR, which appears to subdivide the domain. Most importantly, the analysis highlights the large fraction of diversity that is currently only accessible via cultivation-independent genome-resolved approaches.” (Hug et al., 2016)
    
    16. Mars is a barren planet with no standing liquid water anywhere on its surface. Why, then, is there so much interest in Mars as an abode for life? What kind of life might be present there, and where might it reside?
    “Currently, neither liquid water nor the liquid brine unit is stable on the surface of Mars; however, they may be present briefly in very few areas of the earth. It is unlikely that pure liquid water will be present on the surface of Mars, even if briefly, as a result of evaporation in the very dry atmosphere, inhibiting the formation of the liquid part, whenever the area of ​​temperature and pressure is high enough that the water do not freeze or boil. The exception to the current is that liquid water monolayers, called sub-cooled liquid surface water, can exist on most of the Martian surface. in very few places, there may be liquid brine briefly on the surface, as a result of the type of refrigerant temperature, close to ice or frost deposits, whenever sublimation can be stifled by the presence of almost saturated air.”(Martínez and Renno, 2013)
    
    17. What characteristics define a “life” form?
    “To be habitable, a world (planet or moon) cannot be placed within the stellar habitable zone (HZ), and the worlds within the cycle do not appear to be essentially habitable. Here, we tend to illustrate, however, the recurrent warming of events will make terrestrial or icy worlds on the other side of the stellar cycle habitable. Scientists have developed language that neglects the...