Word of the day THE HINDU IN SCHOOL I MONDAY I SEPTEMBER 29 I 2014 Intricate (adj): Complicated or detailed Used in a sentence: Kashmir carpets have intricate patterns. Suggested by: Zaki Mazhar Kaify. Your turn! Pick a word from today’s The Hindu in School whose meaning you do not know and send it to us at [email protected] SCIENCE & TECH (Subject: Word of the day) 3

Jonathan Freundlich Did you know? Have you ever tried to count the Water found in ● Ancient Greeks stars in the night sky? Have you named our Galaxy ever wondered how many worlds the Milky Way like our Solar System could exist Faraway, exoplanet's in the vastness of the Universe? because it appears Most shining dots you see in the as a milky white night sky are stars like our Sun. glowing band across Some are bigger, some are small- the night sky, and atmosphere er. But they are all part of our so close “galaxy” actually Galaxy, the Milky Way. A galaxy is means “milky” in a group of many stars, dust and ancient Greek. gas held together by the gravita- ● Seen from outside, tional force. The same force that holds you to the ground and pre- our Milky Way looks vent Earth to escape from the vi- like a flat disk made cinity of the Sun. There are more of stars, whose than hundred billion stars in the diameter is about Milky Way! 100,000 light-years: Earth and the other planets of light itself takes our Solar System, like Mars or Ju- 100,000 years to piter, orbit around the Sun. Simi- travel from one side larly, there could also be planets to the other! around other stars. A planet orbit- ing around a star which is not our ● As most other stars, Sun is called an exoplanet, and the our Sun rotates first one was discovered in 1995 around the center of FOR THE FIRST TIME An artist's concept of the from a telescope in the South of An artist’s impression of a sunset on Gliese 667 Cc. The planet orbits around the brightest the Milky Way. The silhouette of the exoplanet planet HAT-P-11b as it France. We have now detected star, but two other suns are visible in the sky. CREDIT: ESO/L. CALCADA nearest star to our passes its parent star. PHOTO: AFP over 1800 exoplanets, and we are Sun is named yet only looking at nearby stars. Proxima Centauri As there are billions and billions liquid water on the surface! But and is already 4 Ian Sample of stars in the Milky Way, there ASTROPHYSICAL SERIES: PART- 2 there are also major differences: light-years away could also be billions and billions the full round of seasons only last from us. Astronomers have detected water vapour in the atmo- of exoplanets. thus indicates the presence of a Since it therefore receives more 28 days instead of a year, and sphere of a planet that orbits a star far beyond our solar planet, and also enables to calcu- light from the star, it is very hot three suns should be visible in the ● 51 Pegasi B is system. Detections are indirect late its size. Moreover, the parent and the temperature reaches day sky. This definitively changes named after its host Observations of the Neptune-sized planet, which lies 120 But detecting exoplanets is not star is attracted to the planet in around 1000°C. But like Jupiter, the vista! constellation, light years from Earth in the constellation of Cygnus, easy. Planets don't emit visible the same way that the planet is you wouldn't be able to set foot on We will surely discover more Pegasus, while revealed that its atmosphere was mostly hydrogen with light on their own, and we are attracted to the star. So, as the this planet, as it is entirely made exoplanets in the future, and one Gliese 667 Cc bears around 25 per cent made up from water vapour. blinded by the extreme brightness planet turns around the of the key questions is whether the name of the Until now, researchers have been frustrated in their of the stars around which they or- star, the star also moves life happened in other planets German astronomer efforts to study the atmospheres of planets much smaller bit. Observing an exoplanet is like a little. As the star is than Earth. As we expect to find Wilhelm Gliese, who than Jupiter because their skies were thick with clouds. spotting a firefly in the direction much more massive many more exoplanets, that is catalogued the The problem was so persistent that astronomers had begun of the sun during a bright sunny than the planet, the quite possible! Besides, we are yet planet's parent stars to think that all warm, small planets formed with sub- day. movement is very faint, only probing a small area of our in 1957. stantial cloud cover. This is why most detections of but still detectable, and Milky Way. What about other gal- But writing in the journal Nature, scientists in the U.S. exoplanets are indirect. For ex- it even permits to deter- axies? There are many more gal- ● While Earth takes a describe how they found a Neptune-sized planet with ample, when a planet passes in mine the mass of the planet. of gas! axies in the Universe, and thus full year to complete cloud-free skies, enabling them to make detailed mea- front of its parent star, the lumi- Gliese 667 Cc is a rocky exopla- even more stars. So many that the its revolution around surements of a small planet’s atmosphere for the first time. Gaseous 51 Pegasi B nosity of the star slightly decreas- net that is much more similar to thought makes me dizzy! the Sun, 51 Pegasi B How did they study? es, and as the planet continues its 51 Pegasi B is the first exoplanet Earth. It is just slightly smaller (Jonathan Freundlich is a PhD circles around its orbit, this is due to happen at reg- that was ever detected. It is a gase- than our planet, and its surface student at the Paris Observatory, star in just a few The planet, named HAT-P-11b, is about four times the ular intervals. Detecting period- ous planet like Jupiter, but it is temperature might be very close in France, working on star forma- days diameter of Earth. It orbits so close to its star that surface ical drops of the star luminosity much closer to its parent star. to Earth's. There could even be tion and galaxy evolution) temperatures reach more than 600C and a year passes in five Earth days. Like our own Neptune, the planet lacks a rocky surface — it’s a ball of gas — and is thought to be lifeless. Scientists from the University of Maryland used Hub- ble’s wide field camera to analyse light from HAT-P-11b’s host star through the planet’s atmosphere. They found that It all started with a bet light with a wavelength of 1.4 micrometres was absorbed, matching the absorption spectrum of water molecules. “Although this planet is not classically habitable, it re- Tune into the story of ment on this day in 1920 in the veals to us that when we find Earth 2.0, we will be able to Pittsburgh Sun for radio receivers use this technique, transmission spectroscopy, to under- how a bet shaped the that were ready to use, his audi- stand its atmosphere and determine the quality of life ence only grew larger. available on its shores,” said Jonathan Fraine, a graduate future of a man and Harry Davis, Westinghouse Vice student and first author on the study. President, saw huge potential in If cloud cover were widespread on smaller planets be- commercial radio broadcasting, prompting him to yond the solar system, astronomers would need radically apply for a commercial license. different approaches or far more advanced technology to broadcasting The license for the arbitrary call probe their atmospheres. “Now we know that not all warm letters KDKA, which was formerly Neptunes form with high-altitude clouds, we can again A.S.Ganesh 8XK, was assigned in mid-October. explore the diversity of planet formation and gain greater KDKA went live on November 2, context for our own creation,” said Fraine. Last week, we saw how two mathe- 1920 and went on to be a pioneer maticians, Urbain Le Verrier and broadcasting station. It was the Biosignatures John Couch Adams, worked out first station to reach out to the Future studies of alien atmospheres may detect propor- the position of the planet Neptune audience with a regular schedule tions of gases that point to life below. On Earth, methane, even before it had even been ob- and achieved many more firsts as ammonia and nitrous oxide are produced mostly by bacte- served. They didn’t bet against commercial broadcast model ria, while oxygen comes from plants and other photosyn- each other as to who would arrive picked up across the globe. thesising organisms. Because the gases are not made in at it first, but if they had, that Conrad received an honorary large amounts by anything else, they are considered “bio- would have been one tough bet to degree of Doctor of Science from signatures”, or signs of life. resolve! the University of Pittsburgh and “Biosignatures are much harder to find, but with bigger, Today, we will be looking at how also the Edison Medal in 1930 exoplanet-specific telescopes and precise instruments, we a bet shaped the future of a man. In (Inset)Frank Conrad, father of radio broadcasting. (Right) Inside a commerical radio station. from the American Institute of should be able to start looking for them too,” said Fraine. — fact, it eventually went on to mark PHOTOS: WIKIMEDIA COMMONS, AFP Electrical Engineers among other © Guardian Newspapers Limited, 2014. the beginning of commercial ra- awards. As for the radio communi- dio. And maybe it is for this reason up with his mechanical abilities, signals transmitted from the Naval After helping test military radio cation that he established, it that Frank Conrad is widely re- prompting his promotion to the Observatory broadcast station apparatus during World War I, reigned for decades till the advent The planet, named HAT-P-11b, is about four ferred to as the father of radio Westinghouse testing department. NAA in Virginia. He not only won Conrad resumed work with his ra- of satellite radio and podcasts. times the diameter of Earth. broadcasting. It was during this period that he the bet, but also moved on to big- dio station after the war. Radio, Write to the writer at Conrad, born to a railroad me- started out inventing, his most no- ger things. which was initially perceived as a [email protected] Like our own Neptune, the planet lacks a rocky chanic in 1874, ended his formal table contribution being the circu- two-way point to point medium, surface — it’s a ball of gas — and is thought to education when he was in his sev- lar type watt-hour metre, which Station in garage was soon turned into a medium be lifeless. enth grade. His desire to work with later became a household item to After the crude receiving device, wherein a single transmitter could tools began to take shape when he measure the consumption of elec- he built his own transmitter, en- be used to reach out to a large Scientists used Hubble’s wide field camera to started out as a bench-hand in the tricity. abling him to open an amateur ra- audience with receivers. analyse light from HAT-P-11b’s host star through Westinghouse Electric Company His interest in radio sparked dio station from his Wilkinsburg He started playing music from the planet’s atmosphere. They found that light in Pittsburgh at the age of 16. from an incident in 1912. In order garage. Licensed as 8XK, Conrad gramophone records in his station, with a wavelength of 1.4 micrometres was to settle a $5 bet (over $100 in started broadcasting and soon be- and he soon started receiving re- absorbed, matching the absorption spectrum of Notable contribution today’s money) regarding the ac- came extremely popular in the quests for specific music. And water molecules. What he lacked through formal curacy of his watch, Conrad built a Pittsburgh area where he could be when the Joseph Horne depart- training, Conrad more than made wireless receiver to hear the time heard. ment store placed an advertise- AN EYE FOR AN I

New insights into Stone Age tools The invisibility cloak Ī Cloaking is the process by which an object They could have been developed in Eurasia and not just in becomes hidden from view, while everything else around the cloaked object appears Africa, says a study. undisturbed...... WASHINGTON: Innovative study published Thursday from the Nor Geghi site in Ī The Rochester Cloak looks like equipment Stone Age tools may have found. Armenia. used by an optometrist. When an object is been developed by people Research published in Research honed in on a placed behind the layered lenses it seems to in Eurasia and contrary to the journal Science shows type of technology known disappear. widely held views that they evidence that refined stone as Levallois, where stone ...... were invented in Africa, a weapons were developed flakes were used to make Ī It provides three-dimensional, continuously in Armenia about 325,000 items like pointed hunting multi-directional cloaking years ago, challenging the weapons. The technology ...... Disclaimer: Readers are requested to verify & theory held by many ar- was an improvement over Ī A simple instruction on how to create a make appropriate enquiries to satisfy themselves about the veracity of an adver- chaeologists that such a more primitive type of Rochester Cloak at home for under $100 is tisement before responding to any published in technology came from stone shaping called available at http://www.rochester.edu/ this newspaper. Kasturi & Sons Limited, the Publisher & Owner of this newspaper, does not Africa then spread to Eu- biface. newscenter/watch-rochester-cloak-uses- I SEE YOU, YOU DON’T SEE ME Scientists at the vouch for the authenticity of any advertisement or advertiser or for any of the advertiser’s pro- rasia as the human popula- ordinary-lenses-to-hide-objects-across- University of Rochester have discovered a way to ducts and/or services. In no event can the tion expanded. continuous-range-of-angles-70592/ hide large objects from sight using inexpensive and Owner, Publisher, Printer, Editor, Director/s, Employees of this newspaper/company be held Experts studied thou- Levallois and biface ...... readily available lenses. PHOTO: REUTERS responsible/liable in any manner whatsoever for any claims and/or damages for advertisements sands of stone artefacts tools. PHOTO: AFP in this newspaper.

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