Los nuevos telescopios que buscarán otros mundos y vida extraterrestre

 

29 septiembre 2015 Última actualización: 11:32 GMT Mientras el mundo se entretiene viendo la rareza de un eclipse de "superluna" y la NASA nos confirma que, en efecto, agua líquida fluyó por Marte, la BBC le echa un vistazo a algunas de las innovaciones que tienen emocionados a los astrónomos. Los actuales telescopios del mundo, tanto en la Tierra como el espacio, han expandido nuestro entendimiento del Universo y nos han traído extraordinarias imágenes de nuestra galaxia y más allá. Pero, dentro de la próxima década, una nueva generación de observatorios increíblemente potentes nos permitirá estudiar más profundamente el Universo con muchísima más claridad. Lee: Por qué es tan importante que haya corrientes de agua en Marte   Contenido relacionado El telescopio Planck muestra gigantes del cosmos   http://www.bbc.com/mundo/video_fotos/2015/09/150928_video_ciencia_astronomia_telescopios_nuevos_wbm

Some see telescope as an opportunity for science education

 

Fri, 05/08/2015 Jennifer Sinco Kelleher, Associated Press   In this photo taken on Wednesday, April 22, 2015, Heather Kaluna poses for a photograph at the University of Hawaii’s Institute for Astronomy in Honolulu. Kaluna, who grew up in a rural town on Hawaii’s Big Island, is on track to become the first Native Hawaiian to earn a doctorate in astronomy from the university. While she’s busy preparing for graduation and defending her thesis, opposition is mounting against building one of the world’s largest telescopes near the summit of a mountain held sacred by Native Hawaiians. Astronomers say Mauna Kea is an ideal location for viewing the skies. (AP Photo/Caleb Jones) HONOLULU (AP) — Before going up to Mauna Kea's summit on Hawaii's Big Island, Heather Kaluna makes an offering to Poliahu, the snow goddess of the mountain. She holds it sacred, as do other Native Hawaiians. The mountain holds another important place in her life: Poised to be the first Native Hawaiian to get an astronomy doctorate from the Univ. of Hawaii, she uses the mountain to gaze at the stars. The two aspects of her identity have collided as protests have erupted in recent weeks over the construction of one of the world's largest telescopes atop the mountain, pitting her against many in her community and even her own family. "It's definitely hard not to feel torn," said Kaluna, 31. "I respect their beliefs but at the same time I think there are a lot of voices not being heard at the moment." Some opponents describe fighting the telescope as an "awakening," an issue Native Hawaiians can band together against. But their reasons vary, from preventing Mauna Kea's desecration to preserving culture to curbing development. For some, however, the telescope represents an opportunity to get Native Hawaiian children interested in science, technology, engineering and math—areas that they've lagged behind. "If you give kids opportunity, give them education, who knows what's possible. We need all the help we can get," said Richard Ha, a Native Hawaiian farmer on the Big Island who has long been supportive of the telescope. Native Hawaiians make up about 23 percent of the state's population. A push by the Univ. of Hawaii has resulted in 12% of STEM majors at its three four-year campuses being Native Hawaiian, up from 9 in spring 2009. During the early years of the $1.4 billion Thirty Meter Telescope project's planning, officials met with Big Island residents and heard there was a desire for more high-tech jobs and education, said telescope spokeswoman Sandra Dawson. "It became clear to us that supporting STEM, we can train kids and then hire them," she said. In November, the telescope launched the Hawaii Island New Knowledge Fund for STEM education. The fund will contribute $1 million annually for the 19-year Mauna Kea sublease with the University of Hawaii. The money is given to two foundations, which distribute the money to schools and nonprofit organizations. The $1 million was recently awarded, but telescope officials held off on announcing the winners. "Everybody was afraid it would get lost in all the shouting," Dawson said. The remaining funds will be disbursed as long as the project is under construction or in operation, she said. Telescope opponent Kealoha Pisciotta calls the fund "buy-off money" that will cost Hawaiians their culture. "The money they've offered is really too little, too late," she said. Construction began last month on Mauna Kea's summit after seven years of environmental studies, public hearings and court proceedings. The Univ. of Hawaii leases the land from the state and subleases it to TMT. Astronomers revere the site because its summit at 13,796 feet is well above the clouds, and provides a clear view of the sky for 300 days a year. There's also very little air and light pollution. Native Hawaiians don't oppose the telescope itself but strongly disagree with its location atop the dormant volcano. A lawsuit challenging the project's construction permit is pending before a state appeals court. "Aspiring to be an astronomer is a wonderful thing," said Kehau Watson, owner of Honua Consulting, which focuses on conservation and community engagement. "But the telescope is not the issue." Its location and the process by which it was approved was the problem, she said. The protests haven't dampened Mailani Neal's passion for astronomy. The Native Hawaiian high school senior at Hawaii Preparatory Academy started an online pro-telescope petition. She was introduced to astronomy while a seventh grader at Kamehameha Schools in Honolulu, learning about Polynesian voyaging and how Hawaiians navigated using the stars. After graduation, she's headed to Rensselaer Polytechnic Institute in Troy, New York, where she plans to major in applied physics with a concentration in space science. Someday, she'd like to return to the Big Island and work at the telescope. "I really love the Hawaiian culture ... but at the same time, I'm a scientist. I was really torn," she said. "I kind of realized that I can use this telescope to be a connection between my cultural side and the scientist in me."

Top five astronomical targets for your new telescope

 

Gizmag's top five astronomical targets for small telescopes (Photo: Shutterstock) Image Gallery (21 images) If you received a telescope for Christmas, or bought one for your kids, your adventures in amateur astronomy are just beginning. Astronomy is the art and science of actually looking at the heavens and even a small telescope will let you find a host of celestial wonders. So where do you begin? Here are our suggestions for five of the most rewarding and spectacular objects with which to start your adventure in amateur astronomy ... plus some important tips on using a telescope. What is a "small" telescope? Roughly speaking, small "beginner" telescopes have an objective (main optic) diameter between about 2.4 and 4.5 inches (60 and 115 mm). These are the scopes for which the sights of our list are intended. If you have a larger scope, your views will be that much better. Before getting to our list of objects, here's a few tips on how to use your new telescope. The single most important tip is to go easy on magnification. Some small "department store" scopes come with eyepiece combinations that will give 500X magnification or more. Using such magnification on a small scope will result in a dim, blurry, and very narrow view. This is too much magnification for the scope, for your scope's mount (vibrations), and for the atmosphere through which you are viewing (turbulence). A rule of thumb is to use magnification between about four and twenty-five times the diameter in inches (between 1 and 0.16 times the diameter in mm) of your scope's objective lens. On rare occasion you can use twice this magnification IF your mount is steady enough. If you have an GOTO mount, don't expect too much of it. These mounts automatically point your scope at a selected object, but while computer pointing is a useful tool, GOTO accuracy on inexpensive scopes is not always the best. Pointing accuracy depends on the setup (usually aiming the scope at three bright stars) and the quality of the gears, which are usually plastic in inexpensive GOTO mounts. As a result, if using the GOTO capabilities of your scope, always use an eyepiece that gives your scope its lowest magnification. This gives you a large field of view, and greatly increases the chance of finding your target. When observing faint objects, give your eyes a chance to adjust to the dark. After 20-30 minutes in the dark, your eyes will be thousands of times more sensitive than when you first go outside. Also, when observing very faint objects, you will see more if you look a bit to the side (averted vision). In this way the light of the object hits the more sensitive rods of the retina. Another factor to keep in mind is light pollution. In crowded cities it is often difficult to see even the brightest stars owing to streetlights and car headlights. There are two main ways to combat this. The best is to take your telescope to a location that has darker skies, typically to rural areas outside of town, although suburban parks may be dark enough to observe many objects. The other approach is to at least set up your telescope in a dark area, say, in the shadow of trees or a building. The lack of direct light will allow your eyes to become dark adapted, and more able to examine the objects you want to see. If neither of these is possible, remember that the Moon and planets can be seen in almost any situation. If you have trouble finding any of the objects listed below, examine the area of the sky using a pair of binoculars. All of them show up clearly in binoculars, and this gives you a quick way to get your bearings. Now let's get down to observing! First, a safety note – NEVER point your telescope at the Sun! While watching the Sun can be done safely with a telescope, you need dedicated equipment to do so. 1. The Moon The best object for examination with a small scope, bar none, is Earth's Moon. The Moon will fill your field of view at about 60 power, and even the smallest telescope will reveal the craters, rills, shadows, ejecta plumes, and other details on the Moon's surface. Lunar map showing the major features of the Moon's surface (Photo: NASA) An excellent beginner's guide for learning the Moon's surface features is the Lunar 100, a list of features in order of increasing difficulty. When you work through this list with a high-quality Lunar map, you will never again look at the Moon in the same way. My favorite Lunar feature is the dual crater Messier/Messier A, #25 on the list, the result of a glancing impact by a pair of small asteroids. 2. Jupiter Right after darkness falls, the brightest object high in the eastern sky is Jupiter, the largest planet in the solar system. Jupiter and its four largest moons roughly as they will appear in a small telescope (Photo: Don Stewart) Even though Jupiter is currently about 630 million km (390 million miles) away from Earth, 40X magnification will make it appear the size of the Moon in the night sky. You should easily be able to see the bands of clouds which circle Jupiter, and Jupiter's four largest moons are easy targets that change position from night to night. The Great Red Spot has been a bit dim in recent years, so the smaller scopes will probably not show it. As a bonus, Jupiter is currently surrounded by the Hyades star cluster, a loose assortment of dozens of stars you will be able to see best using your lowest magnification. The Pleiades photographed using a 90 mm (3.5 in) telescope (Photo: Rochus Hess) Also, about 10 degrees north and slightly west of Jupiter lies the Pleiades star cluster, visible as a tiny "Big Dipper" without your telescope. (Your fist at the end of your outstretched arm is about 10 degrees wide.) Viewed through a telescope, dozens of stars appear in a smaller area than that covered by the Hyades. These are two of the closest star clusters to Earth, at about 150 and 300 light years, respectively. 3. Orion Nebula Next is the sword of Orion. The Orion Nebula (also known as M42) hangs like a sword below the belt of Orion, which is high in the southern sky after dark. Orion's belt and sword. The bright fuzzy spot on the sword is the Orion Nebula, a diffuse nebula that appears about twice the size of the full moon Easily visible to the unaided eye, the Orion Nebula is a stellar nursery where stars are being born at a rapid pace, the nearest such region to Earth at a distance of about 1340 light years. The light of the Orion Nebula comes from an assortment of very hot stars within it. These stars excite some of the gas in the nebula to emit their characteristic spectral lines, while the dust in the nebula reflects their light. Even in a small scope, M42 is a delightful sight. There is a quadruple star called the Trapezium within M42 that can be seen at a magnification of 40 or 50X. This is actually an asterism, an accidental alignment of unrelated stars, but they are unusually close together, with a spread about the same size as Jupiter. It has been suggested that an intermediate mass black hole may reside in the general vicinity of the Trapezium. 4. Andromeda and Triangulum galaxies All of the objects above can be observed from either the northern or southern hemispheres. Now we're going to split our attention to look at a pair of galaxies for each hemisphere. Northern Hemisphere: A little over 10 degrees southwest of the "W" shaped Cassiopeia lies an easily visible white patch in the sky. This is M31, the Andromeda galaxy. The Andromeda galaxy, M31, also showing the satellite galaxies M32 and M110 (Photo: Adam Evans) M31 is very nearly the same size as is our galaxy, and is about 2.5 million light years distant, making it the closest large galaxy to ours. In fact it will collide with our galaxy in a mere four billion years or so. Use your lowest magnification and averted vision to trace out the fringes of the galaxy – in a larger scope and a dark sky it can be traced out to nearly three degrees across. On a good night you may see M31's satellite galaxies M32 and M110 to either side of the flat disk. M33, the Triangulum galaxy, clearly showing the face-on spiral structure (Photo: Hewholooks) The other Northern Hemisphere galaxy is found about 10 degrees southeast of M31, near the tiny arrow-like asterism of Triangulum. This is M33, the third largest member of the Local Group of galaxies that includes M31 and our galaxy. At a distance of about three million light years, M33 can be glimpsed in a very dark sky without optical aid, but from most observing sites binoculars allow it to be easily located. M33 is about double the size of the full moon, and again calls for low magnification and averted vision to make the most of the object. It is a spiral galaxy viewed nearly from atop the spiral, leading to interesting patterns of dark lanes in larger telescopes. 5. Large and Small Magellenic Clouds Southern Hemisphere: At this time of year, southern viewers are fortunate to have the Milky Way's companion galaxies, the Large and Small Magellenic Clouds (LMC and SMC, respectively), in prime position for an early night's observation. The Large and Small Magellanic Clouds. Note the enormous NGC104 globular cluster to the left of the SMC (Photo: ESO/S. Brunier) The LMC is visible as a faint "cloud" in the night sky of the southern hemisphere straddling the border between the constellations of Dorado and Mensa. In total it is nearly as bright as is Alpha Centauri, but is spread over a region of the sky the size of your fist, so appears far fainter. Once again this is a subject for your smallest magnification, but even so the entire LMC will not fit in your field of view. Fortunately there is a great deal of smaller structure to be seen, including the Tarantula Nebula. The SMC is about 20 degrees to the west of the LMC. It is dimmer than the LMC, but also is smaller in extent. As a result, the surface brightness (total brightness/area) is about the same for the SMC and LMC. The SMC has several open clusters and areas of nebulosity, the brightest of which might be glimpsed using a small telescope. Examining the SMC brings an additional award in the form of the second brightest globular cluster, NGC104. NGC104 contains roughly a million stars within a 120 light year sphere. In a small telescope it appears about half the size of the Moon, and with larger magnifications (perhaps 20-25 X) some of the stars will be resolved around the edges of the cluster. Wherever on Earth you live, your adventures in amateur astronomy are just beginning. Even your small telescope will let you find a host of celestial wonders. Source: Astronomical League

European Extremely Large Telescope gets final go-ahead

 

An artist's impression of the E-ELT (ESO/L. Calçada) The ESO has given its European Extremely Large Telescope (E-ELT) the final green light, allowing construction to go ahead at the Chilean site. The telescope is expected to take around a decade to complete, with the final installation expected to facilitate discoveries in fields such as galaxy composition and exoplanets. Construction of the E-ELT was preliminarily confirmed in June 2012, but with the proviso that 90 percent of the required funding (more than €1 billion or around US$1.3 billion) for the project be secured before main construction could begin. With the accession of Poland to the ESO, that line has now been crossed, and 11 of the 14 member states voted in favor of going ahead with project earlier this week (the remaining three members were absent and are expected to continue to support the project). While work on the telescope itself was unable to begin until now, an exception was made for the groundbreaking ceremony, which took place in June of this year. Civil works, such as the construction of an access road, were also permitted to go ahead at the site. The contract for the telescope’s main structure and dome construction – the largest ever from the ESO – will be awarded in late 2015. An image of the E-ELT site as taken from ESO's Paranal Observatory in November 2014, showing site itself in the top left and the under-construction road stretching across the shot (ESO/J. Girard) The E-ELT site is located in Chile’s Atacama Desert, 20 miles (36 km) from the existing Very Large Telescope (VLT), which itself has been instrumental in many important discoveries and observations. These include the mysterious alignment of quasars and the ceasing of star formation in galaxy clusters. The 39-meter aperture optical and infrared telescope is expected to vastly expand our knowledge in a number of areas – studying planets around other stars, the distribution of dark matter and dark energy throughout the Universe, and more. One of its key aims will be to track down and study Earth-like planets, searching for places where life could exist. While 90 percent of the required funds have been obtained, 10 percent of the project cost has been shifted to a second stage, which will include the construction of an adaptive optics system and parts of the main mirror. The telescope will however be functional at the end of the first phase of the construction process. Source: ESO

Giant Gamma Ray Detector Searches for Two Home Sites

 

The Cherenkov Telescope Array will track high-energy photons to probe black holes, dark matter and relativity

 

The telescope array (artist’s impression) will be split across the Northern and Southern hemispheres.
Credit: DESY/Milde Science Comm./Exozet

When very-high-energy gamma-rays slam into Earth’s atmosphere, they trigger particle showers that emit a faint blue light. With this light, astronomers want to trace the rare gamma-rays — only a few strike each square meter of the atmosphere each month — back to their sources, violent objects such as supermassive black holes. But first researchers must find a home for the planned €200-million (US$277-million) Cherenkov Telescope Array (CTA) — or rather, two homes. The telescope will be made up of a 19-dish array in the Northern Hemisphere and a 99-dish array in the south.
At a meeting in Munich, Germany, on 10 April, representatives from the 12 CTA partner countries inched closer to picking the sites. In the Southern Hemisphere, they narrowed the list down to two possibilities: Aar, in southern Namibia; and Cerro Armazones in Chile’s Atacama Desert. In the north, four sites remain in the running: two in the United States and one each in Mexico and Spain.

Some had hoped the panel would pick firm favorites. Last year, a committee of CTA scientists came up with a broader list of sites based on environmental factors such as weather and earthquake risk. The latest decision adds considerations such as political stability and the financial contributions of host nations. “The process is going slower than we’d like, but it’s going, and that’s great,” says Rene Ong, a physicist at the University of California, Los Angeles, who has helped to plan for the CTA.

The array would study photons in an as-yet unexplored energy region: up to 100 teraelectronvolts. Cosmic rays — protons and other nuclei — emit these photons when they are accelerated at the surface of neutron stars and black holes, and when they collide in stellar winds.

The CTA would focus on the center of the Milky Way because of the dark matter thought to lurk there; many theories predict that dark-matter particles could annihilate each other and emit gamma-rays that the CTA should detect. The array would explore physics at energy scales well beyond the scope of most powerful accelerators.

The CTA would also probe theories of quantum gravity, which try to reconcile quantum mechanics with Einstein’s theory of gravity. Some theories predict that very-high-energy photons, with wavelengths approaching the foamy quantum scale of space-time, will travel slightly slower than lower-energy photons from the same source. Observations of gamma-rays at different energies could reveal arrival-time lags.

The CTA panel aims to pick a final southern site by the end of the year. Choosing the northern site may take longer, says panel chair Beatrix Vierkorn-Rudolph, deputy director-general of Germany’s Federal Ministry of Education and Research. Astronomers hope to be ready to start construction by the end of 2015 and to begin full operations in around 2020.

This article is reproduced with permission from the magazine Nature. The
article was first published on April 15, 2014.