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4 Science Wednesday, April 20,1988 THE GAMECOCK 3 I r~~ ?2E2IMfir*r^^n Supernovae in to many astro By JIM NEWMAN this Science editor mass Imagine being able to read by the nal 1 light of a distant star, an intense, fusin point-like source of light so bright in Bu the night sky that the full moon paled solar by comparison. This would be no or- quire dinary star, but one that is dying. In life. its place, a supernova has been born. ply, Though no supernova as tremen- ygen dously powerful as the one portrayed fuse in this scenario has been observed in that recorded history, the possibility beca always exists. A supernova is produc- stabl ed during the final moments in the put, life of a massive star. * r As it exhausts its remaining supply * of nuclear fuel, the star collapses on itself, violently detonating in a titanic outburst of electromagnetic energy I1110? that may rival the luminosity emitted '|sc by the entire galaxy within which it UCMI & lies. A' An enormous quantity of the star's ana' mass is then expelled in all directions to as it flares with the brilliance of a som< billion suns. Within time, it will fade ^or ' and become even less conspicuous dule than before the explosion. f?ur Supernovae have been a fascina- a^,ei tion of many amateur and profes- P?,n sional astronomers through the ^ years. Perhaps that is because not ^u'c even one has been sighted within the SUPC Milky Way in more than 300 years. ^ Many have been detected in a ?. . * number of external galaxies such as SI'1C Andromeda and most recently, in ler ; 1987, within the Large Magellanic ^ron Cloud, a satellite galaxy of the Milky app' Way. Aside from the latter, however, B most were particularly unimpressive forr as seen from Earth and required ., Wa; telescopic aid to see them at all. hyd What distinguished the Large dev< Magellanic Cloud supernova, known bab as Sanduleak -69*202, from other thes similar extragaiactic events was that it is it was brighter and closer than any tain detected since Kepler's supernova of ing 1604. This fortuitous proximity per- heli mitted astronomers their best chance trar ever to study a star in the process of supi tearing itself apart and put current A theories of stellar evolution to the idez acid test. dee* The first few days of observations, pric however, began to unfold into a its theorist's nightmare as Sanduleak win -69'202 seemed to confound long ac- not cepted beliefs regarding stellar death. star ? Trouble with color Jen The problem was not sufficient ^S:> mass, but color. Prior to detonation 8,V( Sanduleak -69*202 resembled a ^aC( perfectly youthful blue supergiant a ^ star. f A star about to undergo a super- not nova explosion is usuall} of a class of eno stars known as red supergiants. us These stars have long since exhausted c|?l their once abundant supply of t10' hydrogen and now fuse heavier rea elements to produce ever higher in- ^or ternal temperatures in order to main- no> tain equilibrium. out Such was the case with Sanduleak 1 -69'202. After fusing most of its re- sue maining hydrogen supply into be helium, a thin outer layer of des hydrogen remained where nuclear It i reactions could still occur because of tha increased temperatures created by the helium now fusing into carbon. A or star like the sun will never get past sin The Crab Nebula in Taurus represents tti ploded In the year 1054. By Scie / stu< fish age anii ! t bio JH9IH9BHIIIH ma off i triguing "} mil nomers am cha stage bccausc of insufficient tiin and the inability to create inter- to i lemperatures sufficient for the or g of even heavier elements. 1 it Sanduleak -69*202, being of 20 on| masses, more than met the re- gro :mcnts for a violent end to its f,s| After exhausting its helium sup- i it went on to fuse carbon, ox- prc , silicon and finally attempted to on] iron. It was at this final point SDe fusion processes were to cease Gtc use iron possesses an exceedingly La e nucleus that requires energy in- tha but returns none. the wring the end ?ft ith its fuel supply effectively ter- anj tted, Sanduleak -69*202 found on the threshold of self- ^1 uetion. to, fter a year of painstaking ysis, astrophysicists have come co' ic conclusion that, though being _ cwhat more compact than usual ||| a star about to supernova, Sanak -69'202 did not tear down the l&| idations of stellar astrophysics h - all, but merely refined a few its. [i ne likely explanation for Sanak -69'202 exploding as a blue {j :rgiant star was its probable lack imvu plpmpnls t aror> mmnlilipc E leavy elements such as carbon, on and oxygen would tend to bet- p absorb electromagnetic radiation b n the core, allowing the surface to r ear cooler and redder. ecause the galaxy within which it a ned, as compared to the Milky * y, ~is. far-.richer in gaseous 1 rogen and helium for star a jlopment, Sanduleak -69'202 pro ly possessed a great deal less of e heavier elements to start with. a possible, therefore, that it main- c ed its bluish color even after leavthe Main Sequence (hydrogenum fusion stage) and went on to isform into a so-called red ergiant. k more popular theory extends the i that Sanduleak -69'202 had ind become a red supergiant, but >r to detonation had shed much of outer layers in a massive solar d. If so, this loss of mass would only have reduced the size of the , but decreased its surface area, erefore, nuclear reactions erated in the core would have far distance to cover, being able to ; Sanduleak -69*202 a hotter surs temperature and, consequently, luer color. til conjecture aside, this event has laid all questions to rest. An irmous distance still lies between and the supernova remnant, no ibt creating gaps in the informal originally gathered. For this din VMIUIMLI ,-) iiiiiaujr jtai 11 the opportunity to study a super/a at relatively close range within own galaxy. t may seem somewhat morbid that h celebrated anticipation would involved with observing the miction of an entire star system, is this very destruction, however, t would provide astronomers with uues wnn wihcii 10 ueiermine 11 when other stars may suffer lilar fates. e tangled remains of a star that ex rofessor work JIM NEWMAN nee editor k. USC marine science professor is jymg uiv uiuci cai 5(imiuic ui i and how it can help determine logy and marine science, hopes tion necessary for better maintain- I fisheries and estuarine ecosystems the South Carolina coast and ~o estimate production in a given " ?' lei y it has been necessary to deterle the growth rates of those fish This cutaway of the hin it. However, many fish ex- mine the age of fish pi ined never appeared to exhibit a inge in length over a period of figure out the annual a e. This has often been attributed but we've now learned a confusion-causing influx of new nual marks are made u recently hatched fish. of smaller marks form t soon became apparent that the Dean said. y way to precisely determine the The technique is so J iwth characteristics of particular is possible to backtrac i was to find out their ages. day a fish was born, ro do this requires the use of a "This tells you a cerl >cess dating back to the 1600's, but history of events in fisl ly rcccntly refined to provide they move from one e icific data on fish ages. The another," he said. >lith, meaning "ear-stone" in Of particular interes tin, is the inner ear component fish found only off tli it makes it possible to determine U.S. coast. This fish 1 : age of a fish by counting a series mined to possess an a' marks or "rings" deposited on it, of around two to th ich in the same way a tree grows displays spawning riti tiual ring layers. other fish species. rhis is a trait apparently found on- "We now know t in most species of fish, but is alien generally three spav mammals. (groupings) that mov< "We've known for years that you course of a year, whicl iild use marks in the otolith to ble by the age study [JSC's biotech program eads state in research EX rom staff reports , with more than 5ZO million in federal and tT~?~~J rivate grants and 150 scientists and staff, USC's iotechnology program leads the state in esearch. This si The Commission on Higher Education recently South Ct pproved creation of the USC Institute for biological Research and Technology, increasing he visibility of biotechnology research programs ind enhancing opportunities for funding and colaborative research with business and industry. g** "The revolution in biological technology will ittect the health and lifestyle or each ot us and is ertain to dominate all other technological ac- By JIM ivities well into the 21st century," said Dr. Frank Science e lerger, director of the newly formed institute. Abou "Recognizing this, USC has made a major ply lies :ommitment to the development of biotechnology spread esearch and looks forward to collaborating with surface. )usiness and industry on research projects that And i lot only will benefit the people in this state, but How ilso have a direct impact on the economy." percent. Already, the center is working with the Green- ly will a vood Genetics Center, Upjohn Company and the fessor I savannah River Laboratory. always 1 Its four laboratories support a number of "Out iiverse research projects, many of which have some ir ong-term applications for genetics, cancer treat- dry, an nent and diagnostic medicine. on," C< "The institute has already had an impact on The ( research in this state and USC," Berger said. face soi "As the center continues to grow, its visibility beneath will increase, becoming a hub for biotechnology quhoun in the Southeast and boosting USC's profile water r< among major research universities in the nation." This proport Researchers investigating ??nert'hse side effects of diabetes '|iatdo1 the wat A husband-wife team of researchers at USC is said. trying to find out why many diabetics go blind, in 3C need kidney transplants or develop vascular but disease at a rate far higher than non-diabetics. quhour The two biochemists, Drs. John Baynes and Alth< Suzanne Thorpe, are focusing on proteins, com- on surl plex combinations of amino acids that are essen- much t tial parts of all living cells. ant* P They have received more than $2 million in underg research funding for their work from several where t sources, including the Diabetes and Kidney ant* Disease Institute of the National Institutes of siderab Health and the American Diabetes Association. "S"1 ihey are investigating how a process called glycation, the interaction between sugar and pro- coa tein in the blood and tissues, can alter and nature damage the structure and function of body plain," proteins. "Thi "Protein is the functional material in the thicken body," Thorpe said. "Muscles, hair, blood and P?edm< the brain are full of protein. So these are depths molecules that make things happen since many of ^he the functions of the body are determined by the layers activities of protein." aquifei Most of the complications of diabetes are caus- capable i i* * .. i _* A a i arp nnl eu indirectly oy cnanges in protein structure, saiu ",v ,,v" Baynes, who also teaches in USC's School of The Medicine. fresh v "The lens of the eye, for example, is supposed shallov to be clear," he said. "A change in the lens pro- depenc tein can bring on cataracts, a leading cause of hard, blindness." these f By understanding the chemistry involved in glycation, Baynes and Thorpe hope to find out were I why diabetics are subject to age-related complica- mount tions and perhaps develop ways to prevent or *"e vo reverse them. a,c 51,1 They are combining basic and clinical research wat with the cooperation of Dr. Kay McFarland, a The USC medical professor and diabetes specialist. depem McFarland provides samples of blood and stream urine from diabetic patients who have agreed to a sevei participate in the study. Baynes uses these samples to prove that the same chemistry that re*y 01 goes on in the test tubes also goes on in people becaus with diabetes. to ?^1 from A s to help S \ Photo courtesy o otolith shows the many layers that help sclent upuiHiions. igc of the fish, "When we just studied that those an- couldn't tell how many coh p of hundreds in because of overlap in fi ed each day," of (fish) length." The most complex speci iccur^,e that it studied so far are marlin a k to the actual fish. Their otolith structur be more difficult to :ain critical life however, because of their h such as when small size. For example, a livil IMIlllClll IU till UlUlllll IIIC thumbnail while a martin's ;t is the spot, a be the "size of the point e southeastern point pen," Dean said, las been deter- A further peculiarity of i verage lifespan why large ones tended to ree years and while smaller marlin were uals similar to automatic conclusion was I the fish, the younger it w< hat there are The aging technique vning cohorts this, however. : in during the "When we compared th i is made possi- the fish to its age we discc Dean said. males could have the same SEA LEVEL y LAND SURFACE / / TERTIARY SAND AQUIFER PL ANATION ^?STc ' *? ??? | CONFINING UNITS (etch details the extent and depth of both tfi irolina. ibsurface watei >t be as plentil NEWMAN ditor t 97 percent of the entire world's water suplocked within several huge basins that over almost three-fourths of the Earth's it's all completely undrinkable. then can a world dependent on such a small ige of fresh water be assured that the suppIways be in abundance? USC geology proDonald Colquhoun indicates this may not be the case. near the Ogalla aquifer there have been istances where irrigation wells have gone d those people have been forced to move olquhoun said. Dgalla aquifer is one of the largest subsurlrces of fresh water in the world and spans i several central U.S. Plains states. As Colpoints out, however, this massive fresh :source too seems to be endangered, problem may also be reaching worldwide ions. Some regions that now contain were once considerably more hospitable. : Middle East, there were once civilizations n't exist anymore because they consumed all er, which destroyed the land," Colquhoun ?uth Carolina, the situation is not as severe, future could be a cause for concern, Col1 said. jugh some sections of the state rely largely face water, such as here in the Midlands, )f the state is heavily dependent on stable UntSfnl UfOtAr rocAnr^or /Iroufn frr*m 'iviiiii ui ? uivi i uai/iu wva uiavrit iiuiu round aquifers. But to determine precisely hese aquifers are located, how deep they are >w much water they contain requires conle analysis. ce about 1976, I've had a number of te students doing geological cross sections in istal plain of South Carolina to outline the of the sediments that underly the coastal ' Colquhoun said. e coastal plain is essentually a wedge of ling sediments that thins out to zero near the "?nt anrl thirkpnc in a cpawflrrl Hirprtinn tr? of 2,000 feet around Myrtle Beach." composition of these sediments and rock are what determine whether or not an is present. "Sands and sandstones are e of holding water whereas clays and muds t," Colquhoun said. Piedmont has some difficulty iri obtaining vater simply because the coastal plain is so v throughout the area. "The Piedmont is lent on fracture systems present within very consolidated rock," he said. "It is within ractures that ground water is found." juhoun said that many of these fractures probably created by past seismic activity, ain building and various other stresses. But ids created within the rock by these events iply not big enough to hold great quantities er. Piedmont is therefore rendered largely ient on surface water such as lakes and is where shortages are usually realized when re drought strikes. y recently has the Midlands been forced to lore heavily on subsurface water resources ?e, unlike in the Piedmont, it is much easier :ain. Columbia, for instance, draws water both the Middendorf and Black Creek .C. fisheries annuli as females, but weigh 180 pounds where the female could weigh 4C7&4 pounus, uean saiu. wnai nas happened is the males reach the size * of sexual reproduction and then stop growing, but the otolith keeps adding these features." Dean feels it's important to know age and growth data for every fish because it's difficult to understand firsthand which types are important N to the ecosystem. Spot, for example, are used more as an "indicator" fish for monitoring the estuarine ecosystem than for their commercial if John Dtan value. ists deter- "This fish is very abundant, and we believe it plays an integral role in how ecosystems function such as how 'sizes we they capture and transfer energy," lorts came Dean said. requencies Another difficulty facing researchers is the ongoing problem of overif*c r?f fish fishinp rrrtnin fish nnnnlnf inns nd sword- Marlin and swordfish, for example, es tend to caught off the South Carolina coast analyze, were a top dollar commodity a few relatively years ago, but now have been spot may significantly overfished. size of a This has occurred because many ; may only were being caught before they were on a ball- sexually mature. These age studies will likely be useful to those who marlin was manage these types of fish because be female specific sexual and growth-related male. An characteristics can now be determinthe smaller ed, Dean said. is. He stressed the need for a better disproved understanding of fish groups, using the aging method, to prevent e weight of fisheries from having such dif jvered that ficulties with their fish populations in number of the future. SURF1CIAL AQUIFER ?\ / B' IGE\ / CHARLESTON - ? . FLORIOAN AQUIFER -J _ SYSTEM Graphic courtcsy of W. R. Aucotl and G. K. Speiran ie Middendorf and Black Creek aquifer systems in r resources may ful as believed "Out near the Ogalla aquifer there have been some instances where irrigation wells have gone dry, and those people have been forced to move on." Donald Colquhoun USC geology professor aquifers, systems so extensive they reach toward the coast. Colquhoun said, however, that the ease at which fresh water can be obtained from these aquifers changes dramatically as you approach the coast. "The Middendorf aquifer is contaminated by salt water in the Myrtle Beach area, and so they only have the Black Creek aquifer to rely on," he said. Hilton Head has become an area of major concern and has even been classified as an impacted : area. "We're very concerned about this area because if they do use too much, it's quite possible that they will draw in the salt water from the sea," Colauhoun said. "Once that happens your fresh water supply is wrecked." Severe droughts can certainly have hard-hitting effects on these aquifers, especially one like the drought during the summer of 1986. "Droughts can have a very short term, very bad effect, particularly in the areas where the water feeds into the subsurface aquifer system," Colquhoun said. He said a number of creek and river systems feed the Middendorf aquifer. "So if there's a lack of rainfall, anybody in these updip areas starts running into trouble because they are still drawing water and it's not being replenished." This also further reduces flow to the aquifer which lessens its rate of replenishment. The effects of droughts can vary from point to point in a general region, Colquhoun said. "Even when we had the bad drought last summer, people were still filling their swimming pools in Columbia. But it was terrible in certain sections of the Piedmont where they had wells that went and stayed dry for three to four months." The option of converting salt water to fresh has been explored and is a process used extensively on isolated islands such as those in the Caribbean. Colquhoun said, however, the cost overrides the benefits of this method and is not an economical solution. Another potentially more serious danger may affect aauifers in the future. With South Carolina as a prime target for toxic waste dumping in recent years, is there the possibility that some of these hazardous materials could find their way into the state's aquifer network? "I think there's been a lot of realization of the possibility, but obviously you would want to put hazardous waste facilities of any type in areas where they would do the least damage to ground water," Colquhoun said. These would be located in areas called "aquicludes," or regions barren ol aquifers. Colquhoun said that great care should be taken in the vears to come as aquifers come under heavier use in some portions of the state. "We do have state agencies set up to study the water situation and presumably are going to see these problems developing as they come," he said.