Transit Of Venus Research Articles

Jeremiah Horrocks. Venus Seen on the Sun: The First Observation of a Transit of Venus by Jeremiah Horrocks. Trans., Intro., and Notes by Wilbur Applebaum. Leiden: Brill, 2012. Pp. xxiv+82. $136.00 (cloth).

Jeremiah Horrocks. <i>Venus Seen on the Sun: The First Observation of a Transit of Venus by Jeremiah Horrocks</i>. Trans., Intro., and Notes by Wilbur Applebaum. Leiden: Brill, 2012. Pp. xxiv+82. $136.00 (cloth).

Picard SODISM, a Space Telescope to Study the Sun from the Middle Ultraviolet to the Near Infrared

The Solar Diameter Imager and Surface Mapper (SODISM) onboard the Picard space mission provides wide-field images of the photosphere and chromosphere of the Sun in five narrow bandpasses centered at 215.0, 393.37, 535.7, 607.1, and 782.2 nm. The Picard spacecraft was successfully launched on 15 June 2010 into a Sun-synchronous dawn–dusk orbit. The Picard space mission represents a European asset in collecting solar observations useful to improve Earth climatic models. The scientific payload consists of the SODISM imager and of two radiometers, SOlar VAriability Picard (SOVAP) and PREcision MOnitor Sensor (PREMOS), which measure the Total Solar Irradiance (TSI) and part of the Solar Spectral Irradiance (SSI).The SODISM telescope continuously monitors solar activity from the middle ultraviolet to the near infrared spectral ranges and produces solar images that feed SSI reconstruction models. Further, SODISM probes the solar interior via a helioseismic analysis of the solar disc and limb images at 535.7 nm, and via astrometric investigations at the limb. The latter allows us to deduce the spectral dependence of the solar limb profile, and the asphericity of the Sun. Furthermore, SODISM data taken during the transit of Venus allow a determination of the absolute value of the solar diameter. This paper provides a detailed description of the SODISM instrument, including thermo-optical analysis, its different modes of observation, and its first performance in space.

The Plate Scale of the SODISM Instrument and the Determination of the Solar Radius at 607.1 nm

Knowledge of the Solar Diameter Imager and Surface Mapper (SODISM) plate scale is a fundamental parameter for obtaining the solar radius. We have determined the plate scale of the telescope on the ground and in flight onboard the Picard spacecraft. The results show significant differences; the main reason is that the conditions of observation are not the same. In addition, the space environment has an impact on the performance of a metrology instrument. Therefore, calibration in space and under the same conditions of observation is crucial. The transit of Venus allowed us to determine the plate scale of the SODISM telescope and hence the absolute value of the solar radius. The transit was observed from space by the Picard spacecraft on 5 - 6 June 2012. We exploited the data recorded by SODISM to determine the plate scale of the instrument, which depends on the characteristics of optical elements (mirrors, filters, or front window). The mean plate scale at 607.1 nm is found to be 1.0643 arcseconds pixel−1 with 3×10−4 RMS. The solar radius at 607.1 nm from 1 AU is found to be equal to 959.86 arcseconds.

Atmosphere of Venus: Problems in perception

Vladimir Shiltsev, Igor Nesterenko, and Randall Rosenfeld call Mikhail Lomonosov a great Russian polymath (Quick Study, PHYSICS TODAY, February 2013, page 64), and indeed, he is credited with many important discoveries. In astronomy, however, he is almost exclusively remembered for his putative “discovery” of the atmosphere of Venus at the transit of 1761.

Atmosphere of Venus: Problems in perception

The Quick Study regarding Mikhail Lomonosov’s viewing of the 1761 transit of Venus is disturbing for a number of reasons. The authors claim that an achromat objective “focus[es] all colors to the same point,” which is well known to be false. Achromats, whether their two lenses are cemented together or separated by air, bring two wavelengths—typically blue and red light—to a common focus while leaving other wavelengths significantly uncorrected for axial chromatic aberration. But more serious is the authors’ use of smoked glass as the solar filter. Viewing the Sun through smoked glass can damage an eye in several ways. The 1/1700 attenuation cited by the authors for their actual solar filter is dangerously weak. Moreover, placing their smoked glass at the eyepiece rather than at the objective lens makes it even more apt to produce eye damage because of the higher concentration of solar energy at the eyepiece—which therefore needs additional attenuation—coupled with the increased risk that the concentrated heat will cause the filter to crack.The author’s own statement in the article makes the case: “Solar viewing was barely tolerable” with their smoked glass. Naive readers attempting to replicate solar viewing in this fashion risk damaging their eyes. Those readers would probably have no method of verifying the attenuation level of a piece of smoked glass across the UV-visible-IR spectrum, so the experiment would be for them a trial-and-error process. Error in this case could cost one his or her eyesight.© 2013 American Institute of Physics.

From the Transits of Venus to the Birth of Experimental Psychology

I trace the attempts to determine the Earth-Sun distance, which is based on measurements of the solar parallax, from the naked-eye observations of Aristarchus of Samos in antiquity to observations of the transits of Venus in the 18th century, noting the nature of the observational errors involved in them. I then turn to measurements of stellar positions with meridian or transit telescopes in the 17th to 19th centuries using the eye and ear method of observation. I show how an analysis of the observational discrepancies in this method led to the discovery of an observer’s “personal equation,” and ultimately to the birth of experimental psychology.

Haydn's Solar Poetics

The sun has long been a potent symbol of worldly power, mythological cosmology, Christian revelation, and philosophical enlightenment. To conjure with it musically is to open a vast field of the associative possibilities of illumination and its others: figures of emergence, ascension, power, fatal strength, attenuation, obscurity. In his symphonic trilogy on the times of the day—nos. 6 (Le matin), 7 (Le midi), and 8 (Le soir)—Haydn traces the diurnal movement of the sun across all three works in ways that reveal a sophisticated understanding of the sun's many cultural resonances. This opus constitutes, in effect, Haydn's debut at the Esterházy court in 1761, a year in which the Transit of Venus across the sun attracted local and global fascination and intense astronomic study. Beyond demonstrating his cultural range to the court, Haydn's focus on the sun's trajectory also helps to explain many of the puzzling musical features of the trilogy, especially the unusual slow movements. These works cast new light on Haydn's return to musical settings of the diurnal cycle at the dusk of his career, in The Creation (1798) and The Seasons (1801), and reflect the Enlightenment composer's engagement with multiple fields of knowledge and experience.

Book Review: Horrocks on the Transit of Venus: Venus Seen on the Sun: The First Observation of a Transit of Venus by Jeremiah Horrocks

HORROCKS ON THE TRANSIT OF VENUS Venus Seen on the Sun: The First Observation of a Transit of Venus by Jeremiah Horrocks. Translated by Wilbur Applebaum (Medieval and Early Modern Science, xviii; Brill, Leiden, 2012). Pp. xxiv + 82. $136. ISBN 978-90-04-22193-2.Why this pricey little book when this stuff is available for free? That was my attitude in initially opening Wilbur Applebaum's new translation of Jeremiah Horrocks's report on the 1639 transit of Venus. Today rare is no longer rare. If I want to read Horrocks's Venus, I can call forth from the internet A. B. Whatton's 1859 translation (http:/faooks.google.com/books?id=P04BAAAAQAAJ); if that is not good enough, I can summon up Johannes Hevelius's 1662 Latin publication, too (http://books. google.com/books ?id=rl9DAAAAcAAJ). Why another?Upon actually reading the book, the reasons why became obvious. This is not just a re-translation of the Hevelius/Whatton publications. As Applebaum explains, Horrocks wrote three drafts of Venus. Hevelius published (and Whatton then translated) the second. The third was more polished, but Horrocks died before completing it. Applebaum uses the third to assemble something largely new. For example, chap. 4, where Horrocks assures the reader that he observed Venus and not a sunspot, is shorter and more direct in Applebaum than in Hevelius/Whatton, and Applebaum's chap. 18 is not in Hevelius/Whatton at all.And even in chapters absent from the third draft, where Applebaum is producing a re-translation, the translation is much improved. Wherever we (I thank Christina Graney for her assistance in evaluating the translation) did a careful comparison, if noticeable differences existed between Applebaum and Whatton, Applebaum had the more faithful rendition. For example, Horrocks discusses how a star vanishes confestim, & quasi ictu oculi [Hevelius, 139] when the Moon occults it. Applebaum's translation (p. 63) follows the Latin flawlessly: immediately, and as if in the blink of an eye; Whatton (p. 198) renders this as very suddenly. Worse, in the same paragraph, Whatton has Horrocks speaking of the stars being covered with a dark shade, but Horrocks is discussing the Moon's dark edge occulting a star, as Applebaum's translation makes clear. Whatton translates Horrocks 's ode to Kepler so freely that it is really Whatton's ode, inspired by Horrocks. Applebaum produces an ode faithful to Horrocks's Latin.This greater fidelity comes at no cost to readability - Applebaum's translation is delightful. …

Book Review: Transits of Venus: Chasing Venus: The Race to Measure the Heavens

TRANSITS OF VENUS Chasing Venus: The Race to Measure the Heavens. Andrea Wulf (William Heinemann, London, 2012), Pp. xxvi + 304. £17. ISBN 978-0-434022-108-6.Readers of this journal will naturally appreciate the timing of this account of the attempts to observe and measure the two eighteenth-century transits of Venus, astronomical events that were the focus of international cooperation and competition. Unlike some of her cast of characters, Andrea Wulf fortunately ensured that everything was ready in good time for the 2012 transit.Wulfs account is a bold attempt to weave together the various stories of the expeditions sent across the globe to observe the transits of 1761 and 1769. Their aim was to provide an improved figure for the size of the solar system from the comparison of observations in different locations. This was a project Edmond Halley had encouraged future astronomers to undertake, knowing in 17 16 that he would not live to the 1760s. With the baton taken up by Joseph-Nicholas Delisle, Nevil Maskelyne and others, Halley's successors attempted to do him proud in their efforts half-a-century later.Telling the story of both transits allows Wulf to make some interesting contrasts. With the 176 1 transit taking place during the Seven Years War - 'the first global war' , we are told (p. 4) - she is able to make much of the difficulties faced by observers such as Le Gentil, Pingre and Mason and Dixon, who all found themselves caught up in the conflict and had to alter their plans accordingly. For other observers, climate was the main challenge. Jean-Baptiste Chappe d'Auteroche, for example, endured sub-zero temperatures as he raced to his intended observing station in Siberia. By 1769, however, Europe was more or less at peace and patronage was easier to secure. Monarchs including George UJ in Britain, Catherine the Great of Russia, and Christian IV of Denmark saw transit expeditions as vehicles for national pride and supported them accordingly. These later expeditions were much better provisioned, therefore, and greatly benefitted from lessons learned in 1761, although they remained subject to the vagaries of the weather (as UK observers experienced only too clearly in 20 1 2).This is a popular history, albeit one that has been fully researched and well referenced. As such, the book follows some of the genre's trends, notably in its attempts to evoke atmosphere and character and to inject drama into the narrative. …

Replicating the discovery of Venus’s atmosphere

The 2012 transit of Venus gave us a chance to reproduce Mikhail Lomonosov’s 1761 observation and demonstrate the excellent quality of 18th-century telescopes.

The Torsind—A Device Based on a New Principle for Non-Conventional Astronomical Observations

The description of a new device which is an improved version of the classic torsion balance is given. The device, which is the so-called “torsind”, seemed to be very sensitive to solar/lunar eclipses, and a Venus transit. It even responded to a solar eclipse when installed underground. The results of the most well-documented cases are described.

MEASURING SOLAR DIAMETER WITH 2012 VENUS TRANSITS

The role of Venus and Mercury transits is crucial to know the past history of the solar diameter. Through the W parameter, the logarithmic derivative of the radius with respect to the luminosity, the past values of the solar luminosity can be recovered. The black drop phenomenon affects the evaluation of the instants of internal and external contacts between the planetary disk and the solar limb. With these observed instants compared with the ephemerides the value of the solar diameter is recovered. The black drop and seeing effects are overcome with two fitting circles, to Venus and to the Sun, drawn in the undistorted part of the image. The corrections of ephemerides due to the atmospheric refraction will also be taken into account. The forthcoming transit of Venus will allow an accuracy on the diameter of the Sun better than 0.01 arcsec, with good images of the ingress and of the egress taken each second. Chinese solar observatories are in the optimal conditions to obtain valuable data for the measurement of the solar diameter with the Venus transit of 5/6 June 2012 with an unprecedented accuracy, and with absolute calibration given by the ephemerides.

Detection of the Rossiter–McLaughlin effect in the 2012 June 6 Venus transit

Abstract Eclipsing bodies on stars produce radial velocity variations on the photospheric stellar lines known as the Rossiter–McLaughlin (RM) effect. The body occults a small area of the stellar disc and, due to the rotation of the star, the stellar line profiles are distorted according to the projected location of the body on to the stellar disc. The effect originally observed in eclipsing binaries was also shown to be produced by extrasolar planets transits. Here we report the detection of the RM effect in the Sun due to the Venus transit of 2012 June 6. We used the integrated sunlight as reflected by the Moon at night time to record part of the transit by means of the high-precision HARPS spectrograph at the 3.6-m La Silla European Southern Observatory (ESO) telescope. The observations show that the partial Venus eclipse of the solar disc in correspondence of the passage in front of the receding hemisphere produced a modulation in the radial velocity with a negative amplitude of ≈−1 m s−1, in agreement with the theoretical model. The radial velocity change is comparable to the solar jitter and more than a factor of 2 smaller than previously detected in extrasolar hot Neptunes. This detection, facilitated by an amplification factor of 3.5 of the Venus radius due to proximity, anticipates the study of transits of Earth-size bodies in solar-type stars by means of a high-resolution spectrograph attached to a 40-m class telescope.

The Hetu'u Global Network: Measuring the Distance to the Sun Using the June 5th/6th Transit of Venus

In the spirit of historic astronomical endeavors, we invited school groups across the globe to collaborate in a solar distance measurement using the rare June 5/6th transit of Venus. In total, we recruited 19 school groups spread over 6 continents and 10 countries to participate in our Hetu'u Global Network. Applying the methods of French astronomer Joseph-Nicolas Delisle, we used individual second and third Venus-Sun contact times to calculate the distance to the Sun. Ten of the sites in our network had amiable weather; 8 of which measured second contact and 5 of which measured third contact leading to consistent solar distance measurements of 152+/-30 million km and 163+/-30 million km respectively. The distance to the Sun at the time of the transit was 152.25 million km; therefore, our measurements are also consistent within 1sigma of the known value. The goal of our international school group network was to inspire the next generation of scientists using the excitement and accessibility of a rare astronomical event. In the process, we connected hundreds of participating students representing a diverse, multi-cultural group with differing political, economic, and racial backgrounds.

Did Lomonosov see the Venusian atmosphere?

Vladimir Shiltsev (Physics Today, February 2012, page 40) properly credits Mikhail Lomonosov with a wide range of scientific achievements. But we have been corresponding with Shiltsev for some months about our realization1 that Lomonosov did not discover the atmosphere of Venus. One of us (Pasachoff) analyzed spacecraft observations of the Cytherean atmosphere at the 2004 transit of Venus,2 and we realized that what Lomonosov reported did not match actual atmospheric observations. NASA’s Transition Region and Coronal Explorer spacecraft detected Venus’s atmosphere for about 20 minutes as Venus’s silhouette entered the Sun’s limb, and again for the first 20 minutes of its exit from the solar disk. Lomonosov saw only a bulge of light—shown in figure 4a of Shiltsev’s article—and a brief flash of light. We think that what he saw was an artifact of his relatively primitive and small telescope rather than the aureole that is sunlight refracted toward Earth by Venus’s atmosphere. Our conclusions were reinforced by observations made during the 2012 transit of Venus.

The day the world discovered the sun: an extraordinary story of scientific adventure and the race to track the transit of Venus

The day the world discovered the sun: an extraordinary story of scientific adventure and the race to track the transit of Venus

The June 2012 transit of Venus

Ground based observers have on 5/6th June 2012 the last opportunity of the century to watch the passage of Venus across the solar disk from Earth. Venus transits have traditionally provided unique insight into the Venus atmosphere through the refraction halo that appears at the planet outer terminator near ingress/egress. Much more recently, Venus transits have attracted renewed interest because the technique of transits is being successfully applied to the characterization of extrasolar planet atmospheres. The current work investigates theoretically the interaction of sunlight and the Venus atmosphere through the full range of transit phases, as observed from Earth and from a remote distance. Our model predictions quantify the relevant atmospheric phenomena, thereby assisting the observers of the event in the interpretation of measurements and the extrapolation to the exoplanet case. Our approach relies on the numerical integration of the radiative transfer equation, and includes refraction, multiple scattering, atmospheric extinction and solar limb darkening, as well as an up to date description of the Venus atmosphere. We produce synthetic images of the planet terminator during ingress/egress that demonstrate the evolving shape, brightness and chromaticity of the halo. Guidelines are offered for the investigation of the planet upper haze from vertically-unresolved photometric measurements. In this respect, the comparison with measurements from the 2004 transit appears encouraging. We also show integrated lightcurves of the Venus/Sun system at various phases during transit and calculate the respective Venus-Sun integrated transmission spectra. The comparison of the model predictions to those for a Venus-like planet free of haze and clouds (and therefore a closer terrestrial analogue) complements the discussion and sets the conclusions into a broader perspective.

Venus seen on the sun: the first observation of a transit of Venus

Venus seen on the sun: the first observation of a transit of Venus

The Venus Transit, the Mayan Calendar and Astronomy Education in Guanajuato, Mexico

In this work we present two aspects of the Astronomy education activities carried out in 2012 by a multidisciplinary group at Universidad de Guanajuato, including specialists in Astronomy, Social Sciences and Environmental Engineering. The first program linked the Venus Transit, occurred in June 2012, with a national campaign of vulgarization of both modern and ancient (Mayan) Astronomy. Professional astronomers all around the country took advantage of the recent myth linked to the end of a large Mayan calendar cycle (13 baktuns, or some 5125 years) happening, after certain authors, in December 2012. In Guanajuato, the Astronomy Department organized live observations of the Venus Transit at two different locations, and complemented with conferences about astronomical events and the fake predictions of disasters linked to the “end“ of the Mayan calendar. This program was very successful not only in Guanajuato but throughout the country, with several thousands of people attending live observations, conferences, expositions, etc.

Venus transit, aureole and solar diameter

AbstractThe possibility to measure the solar diameter using the transits of Mercury has been exploited to investigate the past three centuries of its evolution and to calibrate these measurements made with satellites. This measurement basically consists to compare the ephemerides of the internal contact timings with the observed timings. The transits of Venus of 2004 and 2012 gave the possibility to apply this method, involving a planet with atmosphere, with the refraction of solar light through it creating a luminous arc all around the disk of the planet. The observations of the 2012 transit made to measure the solar diameter participate to the project Venus Twilight Experiment to study the aureole appearing around it near the ingress/egress phases.