Explore the Large Magellanic Cloud

Explore the Large Magellanic Cloud The Large Magellanic Cloud is a satellite galaxy of the Milky Way. It lies some 168,000 light-years away from us in the direction of the southern hemisphere constellations Dorado and Mensa. There is no one discoverer listed for the LMC (as its called), or its nearby neighbor, the Small Magellanic Cloud (SMC). Thats because they are easily visible to the naked eye and have been known to skygazers throughout human history. Their scientific value to the astronomical community is immense: watching what happens in the Large and Small Magellanic Clouds offers rich clues to understanding how galaxies that are interacting change over time. These are relatively close to the Milky Way, cosmically speaking, so they offer detailed information about the origins and evolutions of stars, nebulae, and galaxies.   Key Takeaways: Large Magellanic Cloud The Large Magellanic Cloud is a satellite galaxy of the Milky Way, located some 168,000 light-years from our galaxy.Both the Small Magellanic Cloud and the Large Magellanic Cloud are visible to the naked eye from southern hemisphere locations.The LMC and SMC have interacted in the past and will collide in the future. What Is the LMC? Technically, astronomers call the LMC a Magellanic spiral type galaxy. This is because, while it looks somewhat irregular, it does have a spiral bar, and it was very likely a smaller dwarf spiral galaxy in the past. Something happened to disrupt its shape. Astronomers think it was probably a collision or some interaction with the Small Magellanic Cloud. It has the mass of about 10 billion stars and stretches across 14,000 light-years of space. A portion of the Large Magellanic Cloud showing its many clusters and gas and dust lanes set against a nebula backdrop.   NASA/ESA Hubble Space Telescope The name for both the Large and Small Magellanic Clouds comes from the explorer Ferdinand Magellan. He sighted the LMC during his voyages and wrote about it in his logs. However, they were charted long before Magellans time, most likely by astronomers in the Middle East. There are also records of its sighting in the years before Magellans voyages by various explorers, including Vespucci.   The Science of the LMC The Large Magellanic Cloud is filled with different celestial objects. Its a very busy site for star formation and has many protostellar systems. One of its largest starbirth complexes is called the Tarantula Nebula (due to its spidery shape). There are hundreds of planetary nebulae (which form when stars like the Sun die), as well as star clusters, dozens of globular clusters, and countless massive stars.   Astronomers have identified a large central bar of gas and stars stretching across the width of the Large Magellanic Cloud. It seems to be a rather misshapen bar, with warped ends, likely due to the gravitational pull of the Small Magellanic cloud as the two interacted in the past. For many years, the LMC was classified as an irregular galaxy, but recent observations have identified its bar. Until relatively recently, scientists suspected that the LMC, SMC, and Milky Way would collide sometime in the distant future. New observations show that the orbit of the LMC around the Milky Way is too fast, and it may not ever collide with our galaxy. However, they could pass close together, the combined gravitational pull of both galaxies, plus the SMC, could further warp the two satellites and change the shape of the Milky Way.   A view of the Large Magellanic Cloud and all its star formation regions (in red). The central bar stretches across the entire galaxy. NASA/ESA/STScI Exciting Events in the LMC The LMC was the site in 1987 of an event called Supernova 1987a. That was the death of a massive star, and today, astronomers are studying an expanding ring of debris moving away from the site of the explosion. In addition to SN 1987a, the cloud is also home to a number of x-ray sources which are likely x-ray binary stars, supernova remnants, pulsars, and x-ray bright disks around black holes. The LMC  is rich with hot, massive stars that will eventually blow up as supernovae and then likely collapse to create neutron stars and more black holes.  Ã‚   The expanding cloud of material spreading out from the site of Supernova 1987a as seen in visible light from Hubble Space Telescope and x-rays from the Chandra X-Ray satellite. NASA/Chandra/Hubble   The Hubble Space Telescope has been used often to study small areas of the clouds in high detail. It has returned some very high-resolution images of star clusters, as well as star-forming nebulae and other objects. In one study, the telescope was able to peer deep into the heart of a globular cluster to discern individual stars. The centers of these tightly packed clusters are often so crowded that its nearly impossible to make out individual stars. Hubble has enough power to do that and reveal details about the characteristics of individual stars inside the cluster cores.   Hubble Space Telescope looked at the globular cluster NGC 1854 in the Large Magellanic Cloud. It was able to see individual stars at the heart of the cluster. NASA/ESA/STScI   HST is not the only telescope studying the LMC. Ground-based telescopes with large mirrors, such as the Gemini Observatory and Keck observatories, can now make out details inside the galaxy.   Astronomers have also known for quite some time that there is a bridge of gas that connects both the LMC and the SMC. Until recently, however, it wasnt clear why it was there. They now think that the bridge of gas shows that the two galaxies have interacted in the past. This region is also rich in star-forming sites, which is another indicator of galaxy collisions and interactions. As these objects do their cosmic dance with each other, their mutual gravitational pull tugs gas out into long streamers, and shock waves set off spasms of star formation in the gas.   The globular clusters in the LMC are also giving astronomers deeper insights into how their starry members evolve. Like most other stars, the members of globulars are born in clouds of gas and dust. However, for a globular to form, there must be a lot of gas and dust in a relatively small amount of space. As stars are born in this tight-knit nursery, their gravity keeps them close to each other.   At the other ends of their lives (and stars in globulars are very, very old), they die in much the same way other stars do: by losing their outer atmospheres and puffing them off to space. For stars like the Sun, its a gentle puff. For very massive stars, its a catastrophic outburst. Astronomers are quite interested in how stellar evolution affects cluster stars throughout their entire lives.   Finally, astronomers are interested in both the LMC and the SMC because they are likely to collide again in about 2.5 billion years. Because theyve interacted in the past, observers now look for evidence of those past meetings. They can then model what those clouds will do when they do merge again, and how it will look to astronomers in the very distant future.   Charting the Stars of the LMC For many years, the European Southern Observatory in Chile scanned the Large Magellanic Cloud, capturing images of the stars in and around both Magellanic Clouds. Their data were compiled into the MACS, the Magellanic Catalog of Stars.   This catalog is mainly used by professional astronomers. A recent addition is the LMCEXTOBJ, an extended catalog put together in the 2000s. It includes clusters and other objects within the clouds.   Observing the LMC The best view of the LMC is from the southern hemisphere, although it can be glimpsed low on the horizon from some southerly parts of the northern hemisphere. Both the LMC and the SMC look like ordinary clouds in the sky. They are clouds, in a sense: star clouds. They can be scanned with a good telescope, and are favorite objects for astrophotographers.   Sources Administrator, NASA Content. â€Å"Large Magellanic Cloud.† NASA, NASA, 9 Apr. 2015, www.nasa.gov/multimedia/imagegallery/image_feature_2434.html.â€Å"Magellanic Clouds | COSMOS.† Centre for Astrophysics and Supercomputing, astronomy.swin.edu.au/cosmos/M/Magellanic Clouds.Multiwavelength Large Magellanic Cloud - Irregular Galaxy, coolcosmos.ipac.caltech.edu/cosmic_classroom/multiwavelength_astronomy/multiwavelength_museum/lmc.html.

Using the Spanish Verb Venir

Using the Spanish Verb Venir Venir is a common Spanish verb with a variety of meanings. Fortunately, many of them can be translated using the English verb to come, which also has numerous meanings. Venir is a cousin of English -vent words such as invent and convent as well of venue and venire (a legal term). Keep in mind that venir  is conjugated irregularly, having forms such as vengo (I come) and vendrn (they will come). Using Venir To Refer to Coming From a Place Most commonly, venir is used to talk about coming to or arriving at a place: Cuando yo vine a California fui a Disneylandia. (When I came to California, I went to Disneyland.)Venimos en bus con un maestro y pagamos por nuestro transporte. (We came by bus with a teacher and paid for our own transportation.)Tenà ­a sà ³lo un aà ±o cuando vino desde Espaà ±a. (He was only a year old when he came from Spain.) ¡Ven aquà ­! (Come here!)No vienen hasta las 14.30. (They arent coming until 2:30 p.m.) In context, venir can convey the idea of coming back or returning: No vengas a mà ­. (Tà ­tulo de cancià ³n) (Dont come back to me. (song title))Es importante que vengas temprano. (Its important you come back early.) Using Venir To Point Out Qualities Venir can mean to include, to be, or to have, often in a way that can be translated by to come: El primer iPad no viene con webcam. (The first iPad doesnt come with (include) a webcam.)Estas bicicletas vienen de Surinam. (These bicycles are (come) from Suriname.)El à ºnico que viene con excusas eres tà º. (The only one who comes with (has) excuses is you.)Las servilletas vienen en distintos tamaà ±os. (The napkins come (are) in different sizes.)Viene en caja sellada. (It comes (is) in a sealed box.) Especially when used with bien or mal, venir can be used to indicate suitability: No ser muy famoso me viene bien. (Not being very famous is fine with me.)A ningà ºn paà ­s le viene mal la globalizacià ³n. (Globalization doesnt serve any country poorly.)Al libro le venà ­a bien la promocià ³n. (The promotion was good for the book.) Using Venir With a Gerund Venir can be used as an auxiliary verb with the gerund (also known as the present participle) to indicate a continuing action, often in an increasingly intense way. Hace mucho tiempo que se viene hablando de la necesidad de una nueva constitucià ³n. (The need for a new constitution has been talked about and talked about for a long time.)El presidente viene sufriendo derrota tras derrota. (The president continues to suffer defeat after defeat.)El chofer del camià ³n venà ­a hablando por telà ©fono. (The truck driver kept on talking on a telephone.)   Using Venirse The reflexive form, venirse, like the standard form, can mean to come from a place. But it places more emphasis on where the thing or person has come from. La rumba se vino de Miami. (The rumba came from Miami. La rumba vino de Miami might be translated the same way, but making the verb reflexive calls extra attention to Miami, perhaps because the fact of the sentence may be surprising.)Los turistas se vienen de otros paà ­ses. (The tourists are coming from other countries.)Necesitaremos agua por quà © nos venimos del desierto. (We will need water because we are coming from the desert.) The reflexive can also suggest that the verbs action was sudden or unexpected: Era lo primero que se vino a cabeza. (It was the first thing that came to mind.)Otra hipà ³tesis es que el puente se vino abajo por la fragilidad de sus pilares. (Another theory is that the bridge came down because of the fragility of its pillars.)Los vientos se vinieron de un solo golpe. (The winds came suddenly in a single blow.) Key Takeaways Venir can usually be translated as to come, whether it is used to mean coming from a place or to have a certain quality.Venir can be used with gerunds to indicate continuous action.The reflexive venirse can be used to emphasize the origins of where someone is coming from or to emphasize the suddenness of an action.