The Earth is the yardstick against which the state of isostasy on the terrestrial planets will be assessed in the future. The primary data sets will continue to be gravity anomaly and topography data together with seismic data which have the potential to image the surfaces of flexure directly. We are close to defining the relative contributions of plate flexure and mantle dynamics in contributing to Earth’s topography and gravity fields as well as to its crustal structure and vertical motion history. The acquisition of higher-resolution data will increase the number of estimates of Te of the planets which, in turn, will help us to understand better the complexities of their geodynamical evolution.

Chapter 8 turns to the famous judgment of Julius Caesar’s commentarii (nudi, recti, venusti, 262). Not only textual aesthetics but also visual analogies and the plastic arts underlie Cicero’s judgments. An analysis of statuary analogies and of the fuller contexts for Cicero’s statements suggests a deft ploy on his part. He portrays himself as Phidias crafting a statue of Minerva (the Parthenon Athena) and Caesar as Praxiteles crafting a statue of Venus (the Aphrodite of Knidos). The fundamentally different symbolic resonances of the goddesses simultaneously challenge Caesar’s military accomplishments and underscore Cicero’s civic achievements. Cicero thereby promotes his vision of the need to restore the Roman republic once the civil war has concluded.

Surprisingly, radio observations of the planets also turned up unexpected discoveries. While testing their transit radio array using the Crab Nebula as a reference source, two scientists at the Carnegie Institution Department of Terrestrial Magnetism noticed a strange variable signal that repeated each night. First suspecting that it was ignition noise from a nearby farm vehicle, they later realized that they were detecting radio emission from powerful electrical storms on Jupiter, which was at the same declination as the Crab Nebula as it passed through their fixed telescope beam. Mercury, long thought to have one side bathed in eternal daylight, was found to be rotating. Radio observations revealed the greenhouse effect on Venus, causing surface temperatures to reach over 600 degrees Celsius, and detected intense radiation belts around Jupiter, analogous to the Earth’s van Allen belts. The other giant planets were all found to be warmer than can be explained by solar heating alone. Precise pulsar timing measurements disclosed the first known extrasolar planetary system, a precursor to the thousands of extrasolar planets later discovered by ground and space based optical studies.

Jupiter is subject to World Fate just as much as any other god or human in the Aeneid. He has to unravel the secret scroll of fate to find out what it is. He is presented as a Quindecimvir Sacris Faciundis inspecting the Sibylline Oracles. As a Stoic would, he tries to find out fate and see it through, as when he says, ‘the fates shall find a way’, but like a Homeric deity he can be inconsistent and often goes against it. Juno has complete knowledge of what fate has in store, but she rejects it, so that her interventions can only retard fate by causing individual fates like Dido’s or Turnus’. Her reasons are Homeric: her Homeric self-assertion cannot stand the affronts to her dignity. The individual fortunes of her protégés are tragic in the strict sense. Ultimately, however, she assents to fate, and even shapes it in her bargain with Jupiter. Venus has an ‘impulse’, her love of her son, she knows fate from Jupiter, and she assents to it, but she is capricious even towards Aeneas in her various disguises to him, even while healing him. She is devious in her agreement with Juno to manipulate Dido, but she does make sure fate comes about even through her indirection.

Discovery of dune systems on other planetary bodies (Mars, Venus, Saturn’s moon Titan, and Pluto) have demonstrated the universal nature of the processes of aeolian sediment transport and bedform development despite a wide range of atmospheric properties and sediment composition. Current and future spacecraft missions, especially by landers and rovers, will provide further insights into planetary dune systems.

Chapter 8 turns to the famous judgment of Julius Caesar’s commentarii (nudi, recti, venusti, 262). Not only textual aesthetics but also visual analogies and the plastic arts underlie Cicero’s judgments. An analysis of statuary analogies and of the fuller contexts for Cicero’s statements suggests a deft ploy on his part. He portrays himself as Phidias crafting a statue of Minerva (the Parthenon Athena) and Caesar as Praxiteles crafting a statue of Venus (the Aphrodite of Knidos). The fundamentally different symbolic resonances of the goddesses simultaneously challenge Caesar’s military accomplishments and underscore Cicero’s civic achievements. Cicero thereby promotes his vision of the need to restore the Roman republic once the civil war has concluded.

Here, I look at the concept of a biosignature. The presence of certain gases in a planet’s atmosphere may represent signatures of life-forms. Oxygen is of particular interest. However, while finding a high concentration of oxygen would be suggestive of life, it would not be conclusive if abiotic means of maintenance could be envisaged. Since studies of exoplanet atmospheres are in their infancy, I start in the better-known realm of our solar system, and look at the atmospheres of planets without life, to see the extent to which these vary. Both Mars and Venus have more than 95% carbon dioxide. In contrast, the only solar-system moon to have an atmosphere – Saturn’s Titan – has more than 95% nitrogen. Mercury has virtually no atmosphere. No body in our system has a significant fraction of oxygen except Earth, with about 20%. I examine the techniques of spectroscopy and show how they allow us to see the signatures of particular gases. Then I mention some recent exoplanetary results – such as detection of atmospheric sodium. Finally, I look at proposed direct-imaging space telescopes, notably NASA’s HabEx and LUVOIR, which, if approved, will be missions of extraordinary importance.

Lucretius’ choice of addressee has engaged a number of critical responses, both historicizing and literary-critical. This chapter assesses what is distinctive about Lucretius’ approach to C. Memmius (taken to be the praetor of 58 BC and unsuccessful consular candidate of 53 BC) through comparison with the theory and practice of Epicureanism in contemporary sources, chiefly Philodemus. In the context of Memmius’ disgrace and exile to Athens, Lucretius’ invectives against ambition and similar vices take on an especially mordant character – a frank criticism that contrasts with Philodemus’ more deferential treatment of C. Calpurnius Piso, especially in On the Good King According to Homer. This difference suggests that Lucretius chose Memmius as his addressee for the very reason that this corrupt and failed Roman politician was far from being a promising disciple and badly in need of Epicurean teaching.

This opening chapter surveys the broad range of critical responses to the difficulties presented by DRN 1.44–9 (on the immortality and tranquility of the gods) from Renaissance accounts to the most recent discussions of the problem. The status of the passage as a locus nondum sanatus and its high-profile appearance in the poem’s proem render these verses the most difficult passage for the Lucretian editor. The present discussion weighs complex theories about the verses’ purpose against text-critical theories about the work’s composition and transmission.

This chapter provides a brief review of missions using X-ray, gamma-ray, and neutron spectroscopy to determine the chemical composition of planetary surfaces. This chapter presents the history of planetary radiation measurements, including significant discoveries. Summary tables with links to the archived data provide a resource for readers interested in working in this field. Upcoming missions and possible future directions are described.

Radar has proven to be a powerful tool in planetary exploration. Most of the major solid bodies of the Solar System have been observed with radar, either from Earth or from spacecraft. Planetary radar studies are reviewed in this chapter, with information on the various techniques of radar remote sensing provided along with key results. Recent radar results are emphasized. Concluding remarks are provided on future directions in planetary radar remote sensing.

This chapter investigates how Donne’s ‘To His Mistress Going to Bed’ and Thomas Nashe’s Choice of Valentines make cultural use of Amores 1.5 and 3.7. Framing the analysis through articulations of power and impotence, we see how literary representations of sexual performance or failure reveal covert engagements with questions of politicised myth-making and story-telling. Sex is read here as a vocabulary which has a potent place in the support and subversion of the Augustan and Elizabethan regimes.