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One more planet?
New Products and Discoveries Prof Yash
Pal
PROF YASH PAL |
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One more planet?
THE announcement that scientists have discovered the 10th planet in the solar system has rekindled the old debate: what exactly constitutes a planet? Curiously, no formal definition exists. It is just that any object that revolves around the sun and is large enough can qualify to be called a planet. But there are hundreds of such tiny objects made up of ice and rock in the outer solar system. How do we keep a majority of them out of the list? A similar controversy had arisen in 1930 also when the Pluto was identified. Many had thought that it was too small to be called a planet. Now that a new name —actually it has only been assigned a number (2003-UB313) although the title “Xena” is informally doing the rounds — has been added to the list, there are two choices. Either it may be recognised as the 10th planet, or it may replace Pluto as the ninth planet. The chances of the second option being exercised are remote because of historical reasons. That means that school students may very well have to mug up a new name, as and when it is actually assigned. Coming to the new planet, it was actually imaged unknowingly on October 31, 2003, at Palomar Observatory, by planetary scientists Dr Mike Brown of the California Institute of Technology in Pasadena (California), Chad Trujillo (Gemini Observatory) and David Rabinowitz (Yale University), whose research is partly funded by NASA, but didn’t see it move in the sky until reimaging the same area 15 months later on January 8 this year. Brown and his associates had burnt their fingers in March last year when they announced the discovery of a red planetary body, christened Sedna. Sedna failed the test, since it was likely to be one member of a large population or group of planetary bodies rather than a solitary object. In any case, Sedna was also smaller than Pluto, which has come to be recognised as some sort of a benchmark. Any planetary body smaller than Pluto is not even considered to be called a planet. So, this time they waited patiently to crosscheck the authenticity of their discovery. Even the announcement on July 29 came only when Brown received a phone call claiming that unknown hackers had stolen some of his data and planned to publish it. What also forced their hands was the fact that Spanish astronomers independently discovered one of the two other big new Kuiper Belt objects and on July 28, the Minor Planet Center at the Harvard-Smithsonian Center for Astrophysics in Massachusetts published an orbit based on their data for the object it designated 2003EL61. The new planet is believed to be bigger than Pluto and the largest object found in our solar system ever since Neptune was discovered in 1846. Its diameter may be 3000 km, as compared to the 2300-km Pluto and the 12,756-km earth. We can infer the size of a light bulb far away if we know its wattage. Scientists similarly infer the size of a solar system object by its brightness. According to Brown, even if it reflected 100 per cent of the light reaching it, it would still be as big as Pluto. “I’d say it is probably one and a half times the size of Pluto, but we are not sure yet of the final size,” he adds. Astronomers will take at least six months to determine its exact size. In astronomical matters, distances are measured taking the distance of the earth from the sun as a unit. On that scale, the new planet happens to be 97 units away — nearly 9.7 billion miles and about three times Pluto’s current distance from the sun. It is the farthest-known object in the solar system and the third brightest of the Kuiper Belt objects. (Kuiper Belt is a large ring of icy objects that orbit beyond Neptune and considered to be remnants of the material that formed the solar system.) It is so far away that if one looked at the sun from its surface, the head of a pin held at arm’s length would blot out the sun. It goes round the sun every 560 years and is now at its farthest point from the earth. In about 280 years it will be as close as Neptune. Why was it not noticed earlier? Only because its orbit is at a 45-degree angle to the rest of the solar system — an oddity. The scientists have submitted a name to the International Astronomical Union (IAU) and say that they are confident that their discovery will be designated a planet. The address of the webpage of Mike Brown gives some clue about what the name could be. It refers to a Planet Lila. In their personal interactions, astronomers have been calling it “Xena” after the TV series about a Greek warrior princess. Even Brown says “we’ve always wanted to name something Xena”. At such a great distance, its temperature is only 30 degrees above absolute zero. At least the astrologers have announced that it happens to be so small and distant that it will not make any difference to their predictions. But children surely have more homework to do, and scientists more calculations! |
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New Products and Discoveries THE Inasmet Technology Centre has participated in the METAFLEX project. The aim of this project is to research photovoltaic solar cells to use in building, transport and space sectors. The main innovation of this project is the flexibility that materials by which cells are manufactured provide, and the additional advantage is a weight reduction, comparing to other materials already used, such as glass. The secret of this flexibility consists on the combination of substrata and layers that compose the material for its manufacturing. In both aspects, especially in preparing substrata, the team of INASMET- Tecnalia -member of this project- has provided a great part of the added value this innovative technology implies. Faster supercomputer The Pittsburgh Supercomputing Center (PSC) has switched sports, but its newest and most powerful system, the Cray XT3, is another black-and-gold superstar, say officials. With a nod to the Pittsburgh Steelers quarterback, Big Ben is Cray XT3 serial #1 — the newest stage in the evolution of high-performance computing technology and a major boost for computational science in the United States. Acquired via a $9.7 million grant from the National Science Foundation (NSF) in September 2004, Big Ben — the first XT3 system to ship from Cray — comprises 2,090 processors with an overall peak performance of 10 teraflops: 10 trillion calculations per second. If every person on earth, about 6.5 billion people, held a calculator and did one calculation per second, they would altogether still be 1,500 times slower than Big Ben. Big Ben, whose name also refers to Ben Franklin, will serve as a leading-edge computing resource on the TeraGrid. Built by NSF over the past four years, the TeraGrid is the world’s largest, most comprehensive cyberinfrastructure for open scientific research. The current lead system at PSC, LeMieux (evoking the Pittsburgh Penguins’ owner and star player), has been one of the most productive TeraGrid systems, and although LeMieux remains lively and available for the foreseeable future, Big Ben is expected to take over LeMieux’s role as the TeraGrid resource best suited for very large-scale, demanding projects. Toxic algae On a warm, sunny day, you can hear the presence of a “red tide” of toxic algae on popular Florida beaches, says Barbara Kirkpatrick. It’s not the roar of coastal waves or the gurgle of flowing water, she explains, but “one continuous cough,” as thousands of sunbathers and swimmers respond to airborne irritants that the algae expel in the surf. Kirkpatrick, manager of environmental health at the Mote Marine Laboratory in Sarasota, Fla., heard the sound last February when she visited Siesta Key Beach. Southwest Florida was in the throes of a red tide-in this case, a misnomer because the algae causing it, Karenia brevis, turns water yellow-green. Some traditional signs of the bloom were in evidence on beaches and in canals. Most obviously, manatees were dying. By the end of spring, officials had retrieved more than four dozen sea cow carcasses, weighing up to 1,000 pounds apiece. |
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PROF YASH PAL Electricity is supposed to be a silent server. So why do transformer hum? I do not know whether this is meant to be a clever saying or the questioner really does not know why transformers hum. While recognising the interesting way of asking the question I will hazard an answer to the humming part of the question. You would recognise that nearly all transformers in our country, big ones and those not very big, hum in the same tone. The reason for this remarkable synchrony is that it is not so remarkable - the ac current we use changes direction 50 times a second - it is a 50 cycle alternating current. In a transformer the primary and secondary coils are wound around a laminated soft iron core and the voltage in the secondary is generated through the oscillating magnet field produced by the primary. This 50-cycle oscillation is shared by the laminations of the transformer. It is not surprising, therefore that they would vibrate a little, even when tightly held together, and produce sound at the same frequency. We call this transformer humming. 50-cycle tone is easily recognised even by those who are not very musically inclined. I usually see an appliance in many eateries and sweet shops that has one or two fluorescent tubes in a box like structure with a grid. They are usually kept on the floor. Are they used against flies and mosquitoes? The appliances you have referred to are definitely against flying insects, but more specifically against the moths that multiply in numbers and become troublesome at some times in the year. We all know that moths are attracted by light. In Urdu and Hindi poetry we often talk of the bhanwara, the lover that madly goes on circling its beloved the candle or diya flame till it is singed and dies. The light tubes in the appliance are also to attract the moths. But the poor things fall into a lethal trap produced by an electrified fence around the lights. Moths are big enough to simultaneously touch the live and the neutral wires of the fence and are instantly incinerated. I think these contraptions are placed near the floor to avoid a rain of incinerated remains of moths on tables where the guests are eating. When we enter an airconditioned hotel or store we often encounter a strong gust of air coming down over our heads. What is the purpose of this game? The main objective is to provide a curtain of strong air stream that comes from the top and goes into the vents below while stopping the outside warm, dusty and sometimes smelly air from rushing in through the open door. The air stream is also useful in air washing those who come in from outside. |
