Cassini Imaging Science: Initial Results on Phoebe and Iapetus

The Cassini Imaging Science Subsystem acquired high-resolution imaging data on the outer Saturnian moon, Phoebe, during Cassini's close flyby on 11 June 2004 and on Iapetus during a flyby on 31 December 2004. Phoebe has a heavily cratered and ancient surface, shows evidence of ice near the surface, has distinct layering of different materials, and has a mean density that is indicative of an ice-rock mixture. Iapetus's dark leading side (Cassini Regio) is ancient, heavily cratered terrain bisected by an equatorial ridge system that reaches 20 kilometers relief. Local albedo variations within and bordering Cassini Regio suggest mass wasting of ballistically deposited material, the origin of which remains unknown.

Cassini Imaging Science: Initial Results on Saturn's Atmosphere

The Cassini Imaging Science Subsystem (ISS) began observing Saturn in early February 2004. From analysis of cloud motions through early October 2004, we report vertical wind shear in Saturn's equatorial jet and a maximum wind speed of approximately 375 meters per second, a value that differs from both Hubble Space Telescope and Voyager values. We also report a particularly active narrow southern mid-latitude region in which dark ovals are observed both to merge with each other and to arise from the eruptions of large, bright storms. Bright storm eruptions are correlated with Saturn's electrostatic discharges, which are thought to originate from lightning.

Cassini Imaging Science: Initial Results on Saturn's Rings and Small Satellites

Images acquired of Saturn's rings and small moons by the Cassini Imaging Science Subsystem (ISS) during the first 9 months of Cassini operations at Saturn have produced many new findings. These include new saturnian moons; refined orbits of new and previously known moons; narrow diffuse rings in the F-ring region and embedded in gaps within the main rings; exceptionally fine-scale ring structure in moderate- to high-optical depth regions; new estimates for the masses of ring-region moons, as well as ring particle properties in the Cassini division, derived from the analysis of linear density waves; ring particle albedos in select ring regions; and never-before-seen phenomena within the rings.

Acute reduction in secretory immunoglobulin A following smoking cessation

Smokers report an increase in upper respiratory infections in the early phase of stopping smoking. One possible cause is a depletion in secretory immunoglobulin A (S-IgA) which has been observed in one study. The present study sought to establish this finding in smokers using nicotine patches. Ninety-two smokers, trying to stop smoking, were assessed whilst smoking and for up to six weeks of abstinence. All smokers were prescribed 15 mg 16-h nicotine patches. Among abstinent smokers, changes in S-IgA and saliva volume were assessed. During the preliminary analyses, we observed that for the pre-smoking cessation measure a longer time since the last cigarette was significantly related to lower S-IgA levels (P = 0.006). Consequently, the main analysis, of changes in S-IgA from pre-cessation to post-cessation, was confined to those who had smoked within 0.5-1.5 h of the pre-cessation measure (n = 51). There was a significant decline in S-IgA, relative to pre-smoking abstinence levels, following abstinence of one day (P = 0.027), but levels returned to pre-abstinence values after one week. There was no evidence of any significant changes in saliva volume following smoking cessation, relative to pre-cessation levels. Users of 15 mg patches are likely to experience a decline in S-IgA levels on the first day of smoking cessation, independent of saliva volumes, and this decline in S-IgA is likely to occur acutely, within the first few hours of smoking abstinence. This acute drop in S-IgA appears to stem from a factor other than depletion of nicotine from the body. The observed decrease in S-IgA may help to explain the increased susceptibility of smokers to upper respiratory tract infections in the immediate post-cessation period.

GP prescribing of nicotine replacement and bupropion to aid smoking cessation in England and Wales

AIMS

Prescribing nicotine replacement therapy (NRT) or bupropion for smoking cessation is of considerable importance to public health but little is known about prescribing practices. This paper examines general practitioners' (GPs') prescribing patterns in Britain where these drugs are reimbursed. The results have implications for other health-care systems considering introducing reimbursement.

DESIGN, PARTICIPANTS AND SETTING

Postal survey conducted in 2002 of a random sample of 1088 GPs in England and Wales, of whom 642 (59%) responded.

MEASURES

Number of requests GPs reported having received from patients for NRT and bupropion over the past month, the number of prescriptions they reported issuing and ratings of attitudes to these medications.

FINDINGS

GPs reported receiving an average of 4.3 requests for NRT and 1.9 for bupropion in the previous month. They reported issuing 3.5 prescriptions for NRT and 1.2 for bupropion. Almost all GPs accepted that NRT (95%) and bupropion (97%) should be reimbursable on National Health Service (NHS) prescription. However, a significant minority of those who received requests for prescriptions did not issue any (8% for NRT and 26% for bupropion). This was related to whether they thought these products should be available on NHS prescription for both NRT and bupropion (OR = 0.66, P < 0.05), which in turn was related to beliefs about whether smokers should have to pay for treatment themselves, the cost-effectiveness of NRT/bupropion and the low priority they would give NRT/bupropion in the drug budget. For bupropion, concern about side-effects independently predicted not prescribing [odds ratio (OR) = 1.46, P < 0.03].

CONCLUSION

In the British health-care system, which has a well-established system for technology assessment and professionally endorsed guidelines, a significant minority of GPs decline all patient requests for stop-smoking medicines.

Efficacy of exercise counselling as an aid for smoking cessation: a randomized controlled trial

AIM

To examine whether exercise counselling increases smoking abstinence and reduces tobacco withdrawal and gains in weight and body fat.

DESIGN

A randomized controlled trial.

SETTING

A community-based stop smoking clinic.

PARTICIPANTS

Two hundred and ninety-nine male and female smokers.

INTERVENTION

Participants were assigned randomly to a 7-week smoking cessation programme, including nicotine replacement therapy plus either (i) exercise counselling, or (ii) health education advice with equal contact time as for the exercise counselling condition.

MEASUREMENTS

Six weeks of smoking abstinence was confirmed by expired carbon monoxide.

FINDINGS

There was no significant difference in smoking abstinence between the exercise group (n = 154) and the controls (n = 145) at 6 weeks (39.6% versus 38.6%), nor was there any difference in gains in weight or body fat, although those in the exercise group increased their exercise levels. Exercise participants reported less tension, anxiety and stress than the controls during the first week of smoking abstinence (P = 0.03, 0.01 and 0.04, respectively), less irritability throughout 2 weeks of abstinence (P = 0.03), and less restlessness throughout 3 weeks of abstinence (P = 0.04).

CONCLUSIONS

Adding brief exercise counselling to a smoking cessation programme did not increase smoking abstinence or reduce gains in weight or body fat significantly, although exercise levels were raised and there were some beneficial effects on psychological symptoms.

Increase in common cold symptoms and mouth ulcers following smoking cessation

OBJECTIVE

To examine changes in reports of common cold symptoms and mouth ulcers following smoking cessation. It was hypothesised that reports of these symptoms would increase on stopping smoking.

DESIGN

Smokers were assessed one week before stopping smoking (baseline), then after one, two, and six weeks of smoking abstinence.

PARTICIPANTS

174 smokers attending a seven week smoking cessation programme combining behavioural support with nicotine patches.

MAIN OUTCOME MEASURES

Self reports of cold symptoms, mouth ulcers, and smoking abstinence (validated using expired carbon monoxide) were recorded on each measurement occasion.

RESULTS

Following one, two, and six weeks of smoking abstinence 73.0% (127/174), 57.5% (100/174), and 44.8% (78/174) of the participants, respectively, maintained continuous abstinence and provided reports of cold symptoms and mouth ulcers. For those abstinent from smoking for six weeks, relative to baseline, a significant increase in reports of the number of cold symptoms was observed following one and two weeks of smoking abstinence (p = 0.009 and p = 0.038, respectively) and an increase in reports of mouth ulcers after one and two weeks of abstinence (p = 0.004 and p = 0.008, respectively). Following one week of abstinence significant increases in reports of sore throat, coughing, deafness, and sneezing were observed (p = 0.049, p < 0.001, p< 0.039, and p < 0.003, respectively).

CONCLUSIONS

This is the first study to systematically document significant increases in cold symptoms and mouth ulcers following smoking cessation. Smokers should be informed that they have an increased chance of experiencing these symptoms on stopping smoking. Being psychologically prepared for these effects may reduce their impact on the attempt to stop smoking.

Induction of contact-dependent endothelial apoptosis by osteosarcoma cells suggests a role for endothelial cell apoptosis in blood-borne metastasis

Although tumour cells are believed to migrate between endothelial cells early in metastasis, the possibility remains that endothelial apoptosis may also contribute to the tumour's breach of the vascular barrier. Although seemingly inconsistent with tumour angiogenesis, one publication describes the induction of contact-dependent apoptosis in cultured endothelium by tumour cells. The cell culture data are, however, open to challenge on technical grounds while there are no confirmatory reports. The present paper describes experiments overcoming these limitations. SAOS-2 human osteosarcoma cells and two rat carcinoma cell lines were co-cultured with human umbilical vein endothelial cells (HUVECs) and cultures labelled by surface lectin histochemistry for endothelium. The HUVEC culture density was determined and SAOS-2 cells, but not rat carcinoma cells, were found significantly to reduce HUVEC survival despite the release of potent growth factors as determined in separate experiments with tumour cell conditioned medium. Lectin labelling combined with light microscopy, transmission electron microscopy, flow cytometry for both lectin binding and DNA content, and DNA gel electrophoresis of SAOS-2/HUVEC co-cultures revealed extensive HUVEC apoptosis. These findings indicate contact-dependent endothelial apoptosis by SAOS-2, while this activity appeared weaker and overwhelmed by HUVEC proliferation with rat carcinoma cells. Importantly, this study supports the suggestion that endothelial apoptosis may be important for metastasis and suggests a complex interplay between endothelial proliferation and apoptosis in tumours.

Effect of a GP desktop resource on smoking cessation activities of general practitioners

OBJECTIVES

To evaluate an intervention aimed at increasing the quantity and quality of brief opportunistic general practitioner (GP) advice to smokers encouraging and supporting quit attempts.

DESIGN

Randomized controlled trial with two groups: (1) control and (2) GP desktop resource (GDR). Smoking cessation activities of GPs were assessed by an independent postal survey 1 month after distribution of resource.

SUBJECTS AND SETTING

One hundred and seven GPs in West Dorset.

MAIN OUTCOME MEASURES

GPs' self-reported rates of advising and counselling smokers on cessation over the previous week.

RESULTS

The rate of opportunistic advice per week in the GDR group was 4.9 (SD = 4.1), compared with 2.8 (SD = 1.8) in the control group, F = 8.2, p = 0.0025, one-tailed. The rate of giving counselling was also higher 2.2 (SD = 3.2) in the intervention group versus 1.0 (SD = 1.4) in the control group, F = 4.0), p = 0.025, one-tailed. The proportion who had recommended or prescribed NRT was greater, although not significantly (54%, versus 46%, Fisher's exact p = 0.1, one-tailed).

CONCLUSIONS

The findings indicate that the GDR can increase the rate of delivery of opportunistic advice and provision of counselling. Given the importance of this activity, a larger trial appears to be warranted to examine the long-term effect and the effect on cessation rates in patients.

General Practitioners' views on the provision of nicotine replacement therapy and bupropion

BACKGROUND

Nicotine replacement therapies (NRT) and a new drug, bupropion, are licensed in several countries as aids to smoking cessation. General practitioners (GPs) play a crucial role in recommending or prescribing these medications. In the UK there has been discussion about whether the medications should be reimbursable by the National Health Service (NHS). This study assessed English GPs' attitudes towards reimbursement of NRT and bupropion.

METHODS

Postal survey of a randomly selected national sample of GPs; 376 GPs completed the questionnaire after one reminder; effective response rate: 53%. There was no difference between the responses of GPs who responded to the initial request and those who responded only after a reminder suggesting minimal bias due to non-response.

RESULTS

Attitudes of GPs were remarkably divided on most issues relating to the medications. Forty-three percent thought that bupropion should not be on NHS prescription while 42% thought that it should be (15% did not know); Fifty percent thought that NRT should not be on NHS prescription while 42% thought it should be (8% did not know). Requiring that smokers attend behavioural support programmes to be eligible to receive the medications on NHS prescription made no appreciable difference to the GPs' views. GPs were similarly divided on whether having the medications reimbursable would add unacceptably to their workload or offer a welcome opportunity to discuss smoking with their patients. A principal components analysis of responses to the individual questions on NRT and bupropion revealed that GPs' attitudes could be understood in terms of a single 'pro-con' dimension accounting for 53% of the total variance which made no distinction between the two medications.

CONCLUSIONS

GPs in England appear to be divided in their attitudes to medications to aid smoking cessation and appear not to discriminate in their views between different types of medication or different aspects of their use. This suggests that their attitudes are generated by quite fundamental values. Addressing these values may be important in encouraging GPs to adhere more closely to national and international guidelines.

General Practitioners' views on the English national smoking cessation guidelines

OBJECTIVES

Several countries have followed the US example in publishing national guidelines on smoking cessation interventions. Gauging responses to these guidelines can provide important lessons for future implementation and revision internationally. This study sought to assess General Practitioners' (GPs') views on recently published English smoking cessation guidelines that form the foundation of the UK National Health Service's smoking cessation strategy.

DESIGN

Postal survey in which GPs were asked to judge the appropriateness, effectiveness and practicability of key recommendations for primary care in recent national smoking cessation guidelines.

SETTING

General practice, England and Wales.

SUBJECTS

Random national sample of GPs; 236 GPs completed the questionnaire; effective response rate: 62%.

RESULTS

Only 16% of GPs accepted that all the recommendations in the guidelines were appropriate; 43% accepted that it was appropriate to check the smoking status of known smokers when they visit the surgery and only 30% thought it was practicable to advise smokers to stop at every opportunity. However, 77% of GPs thought that they should provide assistance for smokers wanting to stop; 74% believed that they should refer smokers to specialist services if appropriate and a similar proportion (77%) believed that it was appropriate to recommend nicotine replacement therapy.

CONCLUSIONS

There was greater acceptance by GPs that they should assist smokers wanting to stop than that they should routinely monitor smoking status and give opportunistic advice to patients to stop. Given that opportunistic advice is a cornerstone of the national guidelines there is a need to find ways of reconciling what is being recommended and what GPs feel is appropriate.

The national health demonstration projects

The White Paper Towards a Healthier Scotland pledged 15 million Pounds to support four national health demonstration projects to lead the way in achieving sustained improvement in child health, young people's sexual health, coronary heart disease and cancer. The Starting Well project aims to demonstrate that child health in Glasgow can be improved by a programme of activities which both supports families and provides them with access to enhanced community-based resources. The Healthy Respect project aims to help young people in Lothian develop a positive attitude to their own sexuality and that of others, and a healthy respect for their partners, in order to reduce unplanned teenage pregnancies and sexually transmitted infections. The Have a Heart Paisley project is targeting coronary heart disease among the population of Scotland's largest town. The Cancer Challenge project is piloting a screening programme in the North East of Scotland for the detection of colorectal cancer. Though each project has specific objectives, appropriate to its own topic, all share underlying principles. The projects will act as test beds for action and a learning resource for the rest of Scotland.

Smoking cessation and smoking patterns in the general population: a 1-year follow-up

OBJECTIVE

To assess the prevalence of motivation and behaviours relating to smoking cessation and attempts at harm minimization and the stability of these over a 1-year period; to identify demographic, social, behavioural and psychological predictors of attempts to stop smoking and the success of these attempts.

DESIGN

Face-to-face interviews were carried out with a national sample of UK smokers in April/May 1996 with follow-up 1 year later.

SUBJECTS

The original response rate was 61% (1478 of 1911 adult smokers), and of these 1012 were followed-up 1 year later (68% of those who were originally contactable).

RESULTS

Thirty-one per cent of smokers reported making at least one quit attempt during the follow-up period and 17% made a quit attempt in the first 9 months of that period. Of these 29% were still not smoking at least 3 months later. Fifty-one per cent of smokers had tried to cut down in the year leading up to the first survey. There was a fair degree of consistency over time in individual smokers' desires and intentions to stop smoking across both surveys and in the incidence of quit attempts and attempts to cut down. Beliefs about the effects of smoking on future health and having a partner who disliked their smoking were positively associated with making a quit attempt at follow-up while reporting enjoying smoking at baseline was negatively associated with making a quit attempt at follow-up. Time to first cigarette of the day and age of starting smoking were positively associated with success of quit attempts.

CONCLUSIONS

Motivation and behaviours relating to smoking cessation are prevalent and fairly stable over time. Different factors appear to be related to attempts to stop and the success of those attempts. Interventions to increase smoking cessation in the population should take account of this.

Smoking cessation activities by general practitioners and practice nurses

OBJECTIVES

To assess general practitioners' and practice nurses' self reported behaviour, attitudes, and knowledge in relation to smoking cessation.

DESIGN AND SETTING

Two postal surveys of random national samples of 303 GPs (survey 1) and 459 practice nurses (survey 2) covering England and Wales; effective response rates were 75% and 96%, respectively.

RESULTS

Survey 1 found that 96% of GPs accepted that intervening against smoking was part of their role and almost all (99%) said that they recorded smoking status when patients registered; 57% reported that they routinely updated their records on smoking status, 50% said they advised smokers to stop during most or all consultations, and 76% said they advised smokers to cut down if they cannot stop. A large majority (83%) said they either recommended or prescribed nicotine replacement therapy (NRT). Although most GPs (86%) thought that NRTs were effective, only a minority thought they were worth the cost (47%) or should be on National Health Service (NHS) prescription (32%). There was little evidence that previous training in smoking cessation was associated with more activity, more positive attitudes, or greater knowledge. Survey 2 found that almost all practice nurses (99%) agreed that intervening against smoking was part of their role and 95% said they advised patients to stop at least occasionally; 71% said they advised smokers to stop at most or all consultations. A majority (74%) said that they recommended NRT to their patients. As with the GPs most practice nurses thought that nicotine replacement was effective (79%), but fewer (42%) thought the cost was justified, and only about half (53%) thought it should be available on NHS prescription. Nurses who said they had been trained in smoking cessation engaged in more activity relating to smoking cessation, had more positive attitudes, and were more knowledgeable.

CONCLUSION

GPs and practice nurses accepted that intervening with smoking was an important part of their role and a large majority reported that they intervened at least with some smokers. This represents a promising baseline from which to proceed in terms of implementation of the new smoking cessation guidelines, but it is hoped that improvements can be made in terms of the frequency of updating records and intervening, and acceptance of the cost-effectiveness of NRT as a life preserving intervention.

Prometheus: Io's wandering plume

Unlike any volcanic behavior ever observed on Earth, the plume from Prometheus on Io has wandered 75 to 95 kilometers west over the last 20 years since it was first discovered by Voyager and more recently observed by Galileo. Despite the source motion, the geometric and optical properties of the plume have remained constant. We propose that this can be explained by vaporization of a sulfur dioxide and/or sulfur "snowfield" over which a lava flow is moving. Eruption of a boundary-layer slurry through a rootless conduit with sonic conditions at the intake of the melted snow can account for the constancy of plume properties.

Does exercise aid smoking cessation? A systematic review

AIMS

To assess the effectiveness of exercise-based interventions in smoking cessation.

DESIGN

A systematic review was conducted of articles published between 1980 and 1999. The review focused on randomized controlled trials (RCTs) in which the specific effects of exercise on smoking abstinence were examined. The primary dependent variable was smoking abstinence. Other studies which had both exercise programming as an independent variable and smoking behaviour as a dependent variable are briefly discussed.

PARTICIPANTS

The review included interventions targeting both healthy individuals and those with specific medical conditions.

SETTINGS

The interventions were delivered in both community and inpatient settings.

MEASUREMENTS

Information extracted from each article included details of the participants, exercise and smoking cessation programmes, control conditions, exercise adherence rates, length of follow-up and outcomes.

FINDINGS

Of the eight trials satisfying our inclusion criteria, only two trials found a positive effect for exercise on smoking abstinence. The others showed no effect.

CONCLUSIONS

There is some evidence for exercise aiding smoking cessation. Of the two trials finding a positive effect one was rigorously designed, the other was found to have numerous methodological limitations. Trials showing no effect lacked sensitivity. This was principally because of small sample sizes and inadequate measurement and control of exercise adherence. There is a need for more rigorously designed studies in this area.

Exercise interventions for smoking cessation

BACKGROUND

Taking exercise may help people give up smoking by moderating the effects of nicotine withdrawal.

OBJECTIVES

To determine whether exercise-based interventions combined with a smoking cessation programme are more effective than a smoking cessation intervention alone.

SEARCH STRATEGY

We searched The Cochrane Tobacco Addiction group specialised register for studies including the terms 'exercise' or 'physical activity' in February 2000.

SELECTION CRITERIA

We included randomised trials comparing an exercise programme as an adjunct to a cessation programme with a cessation programme alone, recruiting smokers or recent quitters, and with a follow-up of 6 months or more.

DATA COLLECTION AND ANALYSIS

We extracted data on study characteristics and smoking outcomes. Because of differences in studies we summarised the results narratively, making no attempt at meta-analysis.

MAIN RESULTS

We identified eight trials, six of which had fewer than 25 people in each treatment arm. They varied in the timing and intensity of the smoking cessation and exercise programmes. Only one trial showed a significant benefit from the exercise programme at long term follow-up.

REVIEWER'S CONCLUSIONS

Only one of the eight trials offered evidence for exercise aiding smoking cessation but the other trials were too small to exclude reliably an effect of intervention. Trials are needed with larger sample sizes, equal contact control conditions, tailored and lifestyle exercise programmes and measures of exercise adherence.

Use of a focussed teen prenatal clinic at a military teaching hospital: model for improved outcomes of unmarried mothers

We evaluated the utility of a focussed, multidisciplinary adolescent clinic in improving perinatal outcomes. The study population included all delivering unmarried teenagers (13-19 years) from January 1, 1993 to December 31, 1995 attending the focussed adolescent obstetrical clinic compared to a similar cohort of married teenagers (13-19 years), married 20-24 year-old patients, and unmarried 20-24 year-old patients. There were no statistical differences in chorioamnionitis, intrauterine growth retardation (IUGR), postpartum haemorrhage, maternal weight gain, mean gestational age at delivery, preterm delivery rates (<37 weeks), low birth-weight (<2,500 g), Caesarean delivery, postterm delivery rates (>41 weeks), macrosomia (>4,000 g), placental abruption, chronic hypertension, alcohol use, Apgar scores or stillbirth rates or neonatal death rates among the 4 groups studied. Statistical differences were noted in mean delivery weights (p<0.05), preeclampsia (p<0.004), gestational diabetes (p<0.01), history of substance abuse (p<0.0001), tobacco use (p<0.0001), and forceps delivery rates (p<0.004). However, in the teen cohort none of these differences appeared to adversely affect perinatal outcomes in our patients. The focussed, adolescent obstetrical clinic appears to provide perinatal morbidities equal to a low-risk, general population generating better than expected outcomes for pregnant teenagers.

Evidence for non-synchronous rotation of Europa. Galileo Imaging Team

Non-synchronous rotation of Europa was predicted on theoretical grounds, by considering the orbitally averaged torque exerted by Jupiter on the satellite's tidal bulges. If Europa's orbit were circular, or the satellite were comprised of a frictionless fluid without tidal dissipation, this torque would average to zero. However, Europa has a small forced eccentricity e approximately 0.01 , generated by its dynamical interaction with Io and Ganymede, which should cause the equilibrium spin rate of the satellite to be slightly faster than synchronous. Recent gravity data suggest that there may be a permanent asymmetry in Europa's interior mass distribution which is large enough to offset the tidal torque; hence, if non-synchronous rotation is observed, the surface is probably decoupled from the interior by a subsurface layer of liquid or ductile ice. Non-synchronous rotation was invoked to explain Europa's global system of lineaments and an equatorial region of rifting seen in Voyager images. Here we report an analysis of the orientation and distribution of these surface features, based on initial observations made by the Galileo spacecraft. We find evidence that Europa spins faster than the synchronous rate (or did so in the past), consistent with the possibility of a global subsurface ocean.

Galileo multispectral imaging of Earth

Nearly 6000 multispectral images of Earth were acquired by the Galileo spacecraft during its two flybys. The Galileo images offer a unique perspective on our home planet through the spectral capability made possible by four narrowband near-infrared filters, intended for observations of methane in Jupiter's atmosphere, which are not incorporated in any of the currently operating Earth orbital remote sensing systems. Spectral variations due to mineralogy, vegetative cover, and condensed water are effectively mapped by the visible and near-infrared multispectral imagery, showing a wide variety of biological, meteorological, and geological phenomena. Global tectonic and volcanic processes are clearly illustrated by these images, providing a useful basis for comparative planetary geology. Differences between plant species are detected through the narrowband IR filters on Galileo, allowing regional measurements of variation in the "red edge" of chlorophyll and the depth of the 1-micrometer water band, which is diagnostic of leaf moisture content. Although evidence of life is widespread in the Galileo data set, only a single image (at approximately 2 km/pixel) shows geometrization plausibly attributable to our technical civilization. Water vapor can be uniquely imaged in the Galileo 0.73-micrometer band, permitting spectral discrimination of moist and dry clouds with otherwise similar albedo. Surface snow and ice can be readily distinguished from cloud cover by narrowband imaging within the sensitivity range of Galileo's silicon CCD camera. Ice grain size variations can be mapped using the weak H2O absorption at 1 micrometer, a technique which may find important applications in the exploration of the moons of Jupiter. The Galileo images have the potential to make unique contributions to Earth science in the areas of geological, meteorological and biological remote sensing, due to the inclusion of previously untried narrowband IR filters. The vast scale and near global coverage of the Galileo data set complements the higher-resolution data from Earth orbiting systems and may provide a valuable reference point for future studies of global change.