Jupiter’s Bruises

(In 1994 the comet Shoemaker-Levy 9 collided with the planet Jupiter, causing great excitement in the world of astronomy. The article which follows was written after the first impact.)

Shoemaker-Levy 9 has plunged into Jupiter, and the Hubble Space Telescope has moved away to look at other objects in space. Amateur astronomers, however, are still watching Jupiter to see what bruises were left on the mighty planet by the comet crash of 1994. There was tremendous excitement in astronomical circles during the collision of comet and planet. It is now time to see what has been learned from this impact.

One question which may never be answered: Was Shoemaker-Levy 9 really a comet, or was it an asteroid instead ? Comets tend to be a mixture of ice, rock and dust, along with other substances, like carbon monoxide, that evaporate quickly to form a halo and a tail. Scientists studying the chemical composition of the spots on Jupiter where Shoemaker Levy 9 (S-L 9) hit thought they might see evidence of water and oxygen, two of the expected products when an icy comet vaporises. But except for one unconfirmed report, researchers have found only ammonia, hydrogen sulphide and sulphur gas.

Asteroids are rockier than comets. Yet it is possible for an asteroid to have a halo or a tail, made mostly of dust. Says Hal Weaver of the Space Telescope Institute: 'The only real evidence that SL-9 was a comet is that it broke apart, and we've never seen that in an asteroid. But maybe this was a fragile asteroid'.

Amateur astronomer David Levy, who with Eugene and Carolyn Shoemaker discovered SL-9, points out that comets were originally distinguished by their appearance. They are objects that look like fuzzy stars with tails, and in any previous century astronomers would have called this discovery a comet. On that basis, argues Levy, 'S-L 9 is a comet, period'.

The apparent absence of water at the impact sites provides a clue about how far the SL-9 fragments penetrated Jupiter's atmosphere before exploding. Theorists think that a layer of water vapour lies some 95 km below the visible cloud tops; above the vapour layer, about 50 km down, are clouds believed to consist of a sulphur compound. Since no water seems to have been stirred up, the explosion probably took place in the presumed sulphide layer.

If researchers confirm‎ that the sulphur rose up from Jupiter, it will be 'a major discovery,' says University of Arizona astronomer Roger Yelle. 'We've always believed that much of the colour in Jupiter's clouds comes from sulphur compounds, but we've never detected them.'

No one knows why the points of impact are so dark, but it is clear that they are very high up in Jupiter's atmosphere, since the planet's stripes can be seen through them. Astronomers believe the collisions will provide an opportunity to study the winds above Jupiter's cloud tops. The mark left by the first impact is already starting to be spread around. There are also hints of seismic waves - ripples that may have travelled all the way to a dense layer of liquid hydrogen thousands of kilometers down and then bounced back up to the surface, creating rings half the size of the planet's visible face. These waves may offer clues to Jupiter's internal structure.

The spots that were made by the collision will undoubtedly blow away eventually, but it's much too soon to tell if there will be any permanent changes in Jupiter. There is still every chance that the impacts, especially from the four fragments that hit in nearly the same place, will destabilise the atmosphere and create a new, permanent cyclone like Jupiter's Great Red Spot.

It's also possible that the show isn't quite over. Theorists using a computer model argue that debris has lagged behind the original 21 major fragments. These stragglers, they predict, will keep hitting Jupiter for months to come. Unlike the previous fragments the latecomer will smash into the near side of the planet, giving astronomers a chance to watch some strikes directly. Is the theory plausible? Says one astronomer, 'We've had so many surprises from S-L 9 already that I wouldn't rule anything out'.

Drugs and Obesity

Thin is in, in America. Not only fashion magazines, but also doctors proclaim the importance of a slim, healthy body. Yet despite the current obsession with the trim, taut and terrific body, Americans are putting on weight. In studies conducted in 1980, one quarter of Americans were found to be overweight. Fifteen years later, that number had risen to one third of the population.

In the past, doctors have always recommended a combination of diet and exercise to combat obesity. With the increase in the number of people who are overweight, however, this solution is increasingly being seen to be ineffective.

Given that diet and exercise often do not help produce weight loss, scientists are becoming convinced that, for many, obesity is a genetic disorder. In 1994 a research group at Rockefeller University discovered in experiments on mice what is now called the obesity, or "ob" gene. In turn this discovery led to the identification of a hormone, termed leptin, that signals to the brain the amount of fat stored in the body. When injected into the rodents, the hormone reduced appetite and increased the body's utilisation of calories, the energy produced by food which the body may convert to fat. With findings like these, a large number of medical experts are turning to a selection of drugs which appear to be safe and effective in reducing weight and maintaining lower weight levels.

Because they see obesity as an illness, these authorities claim that treatment should involve not only diet and exercise but drugs as well. What they have in mind is not just a short course of medication to produce small degrees of weight loss. They want to prescribe long-term, perhaps lifetime, drug therapies, just as they might for high blood pressure or diabetes. Obesity's victims, these doctors hope, will not only be able to lose weight, but will also keep that weight off forever.

Not everyone in the medical community is satisfied with the new therapies. Conservatives are seriously worried that the new drugs are, in fact, merely placebos ("medicines" that have no medical effect but may benefit the patient psychologically), or, worse, are actually detrimental to patients' health. Their concerns are understandable. A few decades ago amphetamines - nicknamed "uppers" or "speed" - were widely prescribed to control weight. Patients became slimmer, but suffered from tension and irritability, high pulse rates, and sleepless nights, side effects that may have outweighed the medical benefits of lower body weight. Conservatives also point out that risky as amphetamines were, they were generally prescribed only for temporary use. Advocates of new drug treatments leave open the possibility that the medications will be prescribed for a lifetime.

While there are at least 5 new diet drugs waiting approval by the us Drug and Food Administration, at the moment, the only diet medication that is normally used in the US is "fen-phen" , a combination of the drugs fenfluramine and phentermine. Fenfluramine boosts serotonin, which elevates mood, while phentermine mimics other substances in the brain. Together, the drugs suppress appetite and increase the rate of burning of calories. As its success becomes more widely known, demand for this medication is increasing. Prescriptions for fenfluramine in 1995 were expected to be four times what they were the previous year.

For several reasons, however, fen-phen is not the perfect diet medication. First, there is some debate over safety, although most fen-phen researchers say the drugs pose minor health risks compared with amphetamines. For most patients the short-term side effects are negligible; phentermine heightens alertness while persuading the body to burn more calories, and fenfluramine, thought to cut cravings for starches and sweets, can cause drowsiness. But some users experience a racing heartbeat and, although rarely, high blood pressure. While its effects are milder than those of amphetamines, the feeling of higher energy that fen-phen stirs can be habit-forming. Used alone, phentermine has enough kick to appeal to recreational drug users, who call it "bumblebee". Perhaps even more importantly for dieters, while the drug may cause initial weight loss, over a period of several years, subjects taking the drugs tended to regain some of the weight they had lost - although at a slower rate than those who did not take fen-phen.

Many conservative doctors, moreover, still remain reluctant to diagnose obesity as a disease. In a 19814 survey of 318 physicians, two thirds said their obese patients lacked self-control, and 39% described them as lazy. This traditional view holds that obesity results from a lack of discipline, correctable by diet and exercise. Since studies show that most dieters eat more than they say - or even think - they do, there is probably some truth in seeing a much simpler cause.

On the other hand, the traditional view is challenged by the discovery of the ob gene, which would seem to place significant weight loss outside the individual's control. Then there is the problem of the ever-increasing numbers of obese people, with the resulting increase in hypertension, and diabetes, leading to kidney failure and heart disease. All of these conditions require medication, if not costly equipment and surgery. If all of these effects of obesity must be treated with medication, why refuse medical treatment to help control body weight? Is not prevention better than a cure?

Introduction of the Aged Pension in Australia

Australia was settled by Europeans in 1788, mainly to house criminals, but with a few independent farmers and business men. The settlements were not wealthy, and there was little help available to those in need: the poor, the sick, the unemployed, the aged. To begin with, what little help was available came in the form of charity: donations of money, accommodation or medical treatment to selected needy. A second approach that began to emerge in the late nineteenth century was that of "universalism". It stressed that all people in society should be entitled to certain benefits -up to a minimum level and across a restricted range of services. This approach was eventually used to argue for the introduction of a pension for the aged poor.

It was an area of welfare which had been the subject of active debate in England since the mid-1880s or earlier. A number of proposals were discussed in England, and by the mid-1890s, in Sydney. These included schemes based on voluntary contributions of money to an insurance fund during working years, on various proportionate compulsory contributions from employer and employee, or on the payment from the state to a defined category of people. The German scheme of compulsory health and unemployment insurance payments from worker, employer and the state, was also examined.

It should be noticed that the proportion of the colonies' populations over 65 years of age was rising steadily. In 1861 in New South Wales it had been 1.4 per cent; by 1891 this had risen to 2.5 per cent, and by 1901 was 3.4 per cent. In absolute numbers in 1901, that was over 46,500 people. In general terms, there was a 60 per cent increase in the ten years from 1891 to 1901 in the number of people over the age of 65 living in the colonies, a rate of growth about twice as fast as that of the general population of the colonies. This demographic fact set the scene for consideration of the problem of the aged poor.

In New South Wales the difficulties of the depression of the 1890s encouraged the Benevolent Society, the largest charity in the state, to support the idea of an age pension because this would ease its own burden. However, it took the positive action of humanitarians to get the movement going. J.C. Neild was both a free- trade politician and an insurance company officer with some experience of the actual conditions of poverty of working-class people struggling to maintain respectability as the implications of age loomed large in their lives. He knew at first hand how difficult it was for such people to maintain insurance policies, however modest. He pressed for action in 1895 to "empty the barracks" (large dormitories to house the poor) of their aged inmates, barracks already so full and overcrowding rapidly. Canon Bertie Boyce and Sir Arthur Renwick added Christian support and energy, convening an important public meeting and promoting the idea in the press. Then the Labor (socialist) Party took up the idea early in 1896.

Government administrators involved in poor relief, such as Sydney Maxted, supported the idea too, because they believed it would be cheaper than institutional care. In 1896 the government therefore selected a group of politicians, a Select Committee, to examine the question of state insurance, old age pensions and invalidity. The Committee found government and voluntary organisers welcoming a pension for the aged as another means of helping the poor, as well as emptying the barracks and saving money. But the chairman of the committee, E. W. O'Sullivan, put an entirely different interpretation on the matter. He did not regard an aged pension as an addition to the instruments of selective charity. He argued in the report for a pension funded by specific community taxes, not one tied to employment or to voluntary contributions. He wanted a pension which, moreover, would be:

A free gift from the State... [to those] who have for a fair period assisted to create our civilisation, aided in the development of the resources of the country, and helped to bear the public burdens of the community by the payment of taxes.

Here was a firm assertion of the universal principle of entitlement based on citizenship. The Select Committee's report also contained enough limitations about potential recipients to make it politically acceptable. It was, with all its ambiguities and qualifications, the working basis of a universalist approach to the problem of caring for the aged poor which asserted a clear claim on their behalf to some degree of dignity and independence as a right. Instead of chancy selective charity leading to early institutionalisation and consequent physical decay, here was an opportunity for social action on a consistent, statutory basis, taking existing family life as its foundation.

The New South Wales Old Age Pensions Act came into being in 1900, followed over the next few years by similar acts in the other states. It was not till 1908 that these quite disparate state arrangements were replaced by Commonwealth (federal) legislation. There were, as almost always in universalist schemes, financial criteria. Onlya specific category of citizens would benefit. Income in excess of £52 per annum or property valued in excess of £310 would deny the pension, while income between £26 and £52 per annum proportionately reduced the pension.

It is clear that the Commonwealth government of the time, led by Deakin for the Labor Party, shared a radical view of social forces which emphasised the problems outside individual control, and the paternal responsibility of the government to acknowledge the universal rights of its citizens. The older tradition of liberal individualism which set such store by self-improvement and personal responsibility was not widely upheld in the federal area. Nor should it forgotten that the worst of the drought of the 1890s was past, and federal government income was buoyant. Arising out of that complex of idealism and pragmatic search for workable cash benefits, the Commonwealth old age pension came into being on 1 July 1909, bringing years of bureaucratic and political manoeuvre to cope with its application, extension or even containment, during which some of the difficulties of universalism were to be vividly revealed.