Nemesis ,the name of our Sun's possible evil twin! Yes, our very own sun could have a twin brother who might have been the reason for major destructions, even the demise of our beloved Dinosaurs. So who is this 'Nemesis'?
According to the research done by Sarah et al. on Embedded binaries and Their dense cores which is a planetary model on how stars are formed and after countless investigations done on dust clouds in the Perseus constellation they've concluded that all stars are born with a companion. To explain further, we need to know what Star system is. Star system or stellar system is a small number of stars that orbit each other bound by gravitational attraction. A star system of two stars is know as Binary star and so on (Triple system, quaternary,etc,.)
For many years, astronomers have wondered if the large number of binary and triple systems of stars in our galaxy are created so close to each other or if they just fall together after they're formed. From many previous researches it was vaguely clear that almost all the stars are born as multiples that often spin away on their own. But this new analysis fixates the claim of born-together hypothesis. Stahler, an astronomer working with Sarah quotes " Our work is a step forward in understanding both how binaries form and also the role that binaries play in early stellar evolution". As a part of the VANDAM survey (The VLA nascent disk and Multiplicity survey) done out of a dense cocoon of dust about 600 light years away that contained a whole nursery of young stars it was clear that all stars are born as binaries. To know more about VANDAM click here
Even if our sun's theoretical sibling cease to exist we cannot see it in our neighbourhood, not until now at least. But their is another hypothesis where some believe that Nemesis pay us a visit every now and then. This could explain the 27-million year cycle of extinctions on earth. So that explains the death of dinosaurs. If not asteroids it has to be this estranged twin !
Richard Muller, another astronomer who studied a red dwarf star about 1.5 light years away found that when this star travels through the icy outer limits of our solar system, it stirs up all the planetary bodies within it's gravity !
Could this be it? On contrary it could just be a dying star manifesting its rage. It's not uncommon for a passing by star to mess things up in a planetary system.  However there is still a fair amount of time for the next cycle of extinction to pop in. We shouldn't overlook the possibilities of an indignant Nemesis destroying life as we know it.. hope not !

The Final Solution


"Those who forget the past are condemned to repeat it."

Nearly 6 million European Jews were ruthlessly killed by Adolf Hitler during the second World War. From 1941 to 1945, Jews were methodically murdered in which is still considered to be one of the 'deadliest genocide in human history' Nearly 42,500 detention facilities were used by the Nazis to imprison Jews and carry out flagrant violations of Human rights. Over 200,000 people are estimated to have been Holocaust perpetrators.  Adolf Hitler managed to manipulate his whole nation, that extermination of Jews is the only solution. Giving his nation a notorious tag called 'Nazi Germany'. Personally, Hitler's persona doesn't bother me a lot. The fact that an estimated number of 200,000 odd Nazis involved directly in massacring 6 million Jews was alarming.
Why did Hitler and Nazis hate Jews? 
According to many historians, Jews are merely the victims of 'Scapegoating'. Hitler blamed that Jews ,are responsible for major events like Germany's loss in World war-1 and economical crisis.But by putting the blame on Jews, Hitler created an enemy. Germans believed him blindly, and assumed that Jews are the real problem. It is a perfect example of Mass Hysteria.
"Believing something blindly" That's something us, humans do a lot. Either its religion or king or a dictator. Humans are the victims of manipulation. We keep proving it throughout our recorded history.
Many believe Hitler invented Antisemitism, Its a No. Of course, he didn't invent it. Hitler built on and used Antisemitic ideas that already existed. He was an Austrian and grew up in Vienna where the Mayor was extremely antisemitic and where hatred of Jews was widespread. These episodes led  Hitler and two hundred thousand people to conclude that Jews are destroying their livelihood. They thought its their 'final' solution. During the era of Holocaust, Nazis also targeted other groups because of their perceived "racial inferiority" : Gypsies, the disabled, some of the slavic people (russians), While some persecuted on political,ideological and behavioral grounds; among them communists, Jehovah's witnesses and Homosexuals.  Killing is unacceptable. We don't have any right to take someone's life.
The holocaust is a history of enduring horror and sorrow. It seems as though there was no spark of human concern, no act of humanity, to lighten that dark history.
Auschwitz-Birkenau Belzec Bergen-Belsen,etc and all other concentration camps where millions cried for help, stuck inside those doomed walls, awaiting their fate. They will be remembered forever.
The Holocaust survivor Abel Herzberg has said: "There were not six million Jews murdered; there was one murder, six million times.".
The words of Elie Wiesel, the Nobel laureate and Holocaust survivor, stand as a testament to why we must never forget this dark period of human history:
"For the survivor who chooses to testify, it is clear: his duty is to bear witness for the dead and the living. He has no right to deprive future generations of a past that belongs to our collective memory. To forget would be not only dangerous but offensive; to forget the dead would be akin to killing them a second time. The witness has forced himself to testify. For the youth of today, for the children who will be born tomorrow. He does not want his past to become their future." Elie Wiesel, Night, Preface to the New Translation (New York: Hill and Wang, c2006), page xv.
RIP- to those who died.
 * -  Photo taken at Yad Vashem, the Holocaust museum in Jerusalem. This image shows a young Jew looking up into the Hall of Names, an exhibit in the museum.

Galaxy Merger

NGC 7714 is a spiral galaxy 100 million light-years from Earth — a relatively close neighbour in cosmic terms. The galaxy has witnessed some violent and dramatic events in its recent past. Tell-tale signs of this brutality can be seen in NGC 7714's strangely shaped arms, and in the smoky golden haze that stretches out from the galactic centre — caused by an ongoing merger with its smaller galactic companion NGC 7715, which is out of the frame of this image.
Credit: ESA,NASA
The gravitationally bound system that binds all the stars visible is referred to as galaxy. It also consists of various other components such as stellar remnants, interstellar gas, dust, and dark matter. Galaxies are categorized according to their visual morphology as elliptical, spiral and irregular. Many galaxies are thought to have black holes at their active centres, for example; The Milky Way's central black hole, known as Sagittarius A*, has a mass four million times greater than the Sun. Our main aim at this passage is to understand why different galaxies could merge, interact together or form starburst galaxies, to this day we people have come across the theory of their probability to collide with one another due to their large separation. This process is their basic way to growth, to become bigger leading to heavy expansion. When the two colliding galaxies both have central black holes, they will tend to sink toward the common centre and eventually join together. This process even provides enough energy for the black holes to cause active nucleus. Further process suggests that the gravitational field of the stars produced in the bulge influences how much mass can be collected in the centre and assembled into the black hole. It has also been observed that jets and winds from the active nucleus can disrupt the star formation in the rest of the galaxy, and that this happens in a fashion that helps regulate the mass in stars to stay proportional to that in the black hole. Taking a closer look at individual galaxies; The Magellanic Clouds are two small galaxies (LMC & SMC) within the Local Group and very close to the Milky Way (Galactic Plane). It is likely that the Milky Way is in the early stages of such an event with them, where it has been set to begin the process of absorption of the two local galaxies. A similar fate may await many other small members of the Local Group, merging either with the Andromeda Galaxy or with the Milky Way. Andromeda lies approximately 220,000 light years across, and it is the largest galaxy of the Local Group, which also contains the Milky Way, the Triangulum Galaxy, and other smaller galaxies. Andromeda galaxy is a spiral galaxy 780 kiloparsecs away from Earth. Andromeda galaxy and Milky Way themselves are speeding towards each other at 300 miles per hour. This might even change the way our sky appears to be, replacing the way it already looks with an image of merging galaxies might feed a possible data to our imagination at this point. When elliptical galaxies collide with each other, the smaller galaxy losing its energy as a whole, tends to come closer and at reaching its maximum, gets captured within and starts to spiral inwards. As a result, they often tend to have multiple nuclei. Various other results from their collision involve large amounts of star formation, high density gas production that provides a lot of fuel for star formation, nucleus absorbs energy hence absorbing young stars which makes it brighter at the infrared region, Because of the dust, the star forming region is hidden in the optical, etc. All of these results comprise, to be known as “starburst galaxies”. Examples; Stephan's Quintet (visual grouping of five galaxies of which four form the first compact galaxy group ever discovered) is one of the famous examples of interacting galaxies, theories of merging of disc galaxies (galaxy characterized by a disc, a flattened circular volume of stars), etc. On a recent note, NuSTAR (NASA's Nuclear Spectroscopic Telescope Array; NuSTAR is a Small Explorer mission led by Caltech and managed by JPL for NASA's Science Mission Directorate in Washington, NuSTAR was developed in partnership with the Danish Technical University and the Italian Space Agency (ASI)) mission, observed theories contrary to our understanding about merging galaxies till date. It gave information over merging of large galaxy 49b and dwarf galaxy 49a, where 49a consists of supermassive black hole that is way powerful than ever imagined. Normally, when two galaxies start to merge, the larger galaxy's central black hole becomes active, voraciously gobbling gas and dust, and spewing out high-energy X-rays as matter gets converted into energy. That is because, as galaxies approach each other, their gravitational interactions create a torque that funnels gas into the larger galaxy's central black hole. But in this case, the smaller galaxy hosts a more energetic and luminous X-rays with a highly active supermassive black hole, and the larger galaxy's central black hole remained relatively quiet. This study should be considered important along with the other theories stated above because it may give new insight into how supermassive black holes form and grow in such huge systems that collide with one another. By examining these formed galaxies, we may also find clues as to how our own galaxy’s supermassive black hole is formed. In several hundred million years, yet another hypothesis states that the black holes of the large and small galaxies will merge into one enormous beast, leaving more room for further discovery.

Wow !

The signal that hit most of our vision, over its’ success of being decoded, is the Wow! signal. On August 15, 1977, a strong narrow band radio signal was received by the Big Ear Radio Telescope of the Ohio State University, United States, then assigned to a SETI project (Search for Extra-Terrestrial Intelligence). Various hypotheses have been drawn over the possibility of a natural origin that has not been completely discounted, assuming the Wow! signal to be considered the best candidate for an alien radio transmission ever received. Astronomer Jerry R. Ehman circled an alphanumeric sequence, 6EQUJ5, which represents the intensity variation of the radio signal over time, measured as unit less signal-to-noise ratio and ranging from 0 to 36, with the noise averaged over the previous few minutes. Each individual character corresponds to a sample of the signal, taken every 12 seconds. It’s strange, over how the scientists did not just think it could mean something but felt it was the utter most important subject to open up institutes and research fields that contributed to knowing the signal ratios and their rate of various other factors. In simple words, SETI wishes to explore life above us that could be benign or a threat to our existence. Prevention being better than cure may just not be for us but to other existing species that we believe in. To catch up more about this signal, its precise origin in the sky was uncertain due to the Big Ear telescope's design, which featured two feed horns, each pointing in a slightly different direction, while following Earth's rotation. The Wow! signal was detected by one of the horns but not by the other, and the data was processed in such a way that it is impossible to determine which of the two horns received the signal. Interstellar scintillation of a weaker continuous signal—similar in effect to atmospheric twinkling could be an explanation, but that would not exclude the possibility of the signal's being artificial in origin. When Ehman went through the entire system over 50 times, he said that the most likely explanation for the signal is from an extra-terrestrial civilization. The previous statement contributes to the significance of scepticism and since then several attempts were made by Ehman as well as by other astronomers to detect and identify the signal again. The signal was expected to appear three minutes apart in each of the telescope's feed horns, but that did not happen. In 1987 and 1989, Robert H. Gray searched for the event using the META array at Oak Ridge Observatory, but did not detect it. In a July 1995 test of signal detection software to be used in its upcoming Project Argus search, SETI League executive director H. Paul Shuch made several drift-scan observations of the Wow! signal's coordinates with a 12-meter radio telescope at the National Radio Astronomy Observatory in Green Bank, West Virginia, also achieving a null result. In 1995 and 1996, Gray again searched for the signal using the Very Large Array, which is significantly more sensitive than Big Ear. Gray and Simon Ellingsen later searched for recurrences of the event in 1999 using the 26m radio telescope at the University of Tasmania's Mount Pleasant Radio Observatory. Six 14-hour observations were made at positions in the vicinity, but nothing like the Wow! signal was detected. But in May 2015, a team of researchers using a Russian radio telescope spotted a strong radio signal coming from the vicinity of the sun like star HD 164595, which lies 94 light-years away from Earth. This could only mean that we could hope to have faith over its re-occurrence and sooner or later decode this mystery.