Fredric William Taylor

• MA, D.Phil.
• Professor Emeritus at University of Oxford

An Oxford atmospheric physicist and experimenter on early NASA weather satellites who revolutionized the field through leadership of the Appleton Laboratory, the Meteorological Office and the Science Board of the IPCC.

On 2015 July 18, near perihelion at a heliocentric distance of 1.28 au, the Visible InfraRed Thermal Imaging Spectrometer (VIRTIS-M) on board the Rosetta spacecraft had the opportunity of observing dust activity in the inner coma with a view of the night side (shadowed side) of comet 67P/Churyumov-Gerasimenko. At the time of the measurements we pre...

Context. On 27 April 2015, when comet 67P/Churyumov-Gerasimenko was at 1.76 au from the Sun and moving toward perihelion, the OSIRIS and VIRTIS-M instruments on board the Rosetta spacecraft simultaneously observed the evolving dust and gas coma during a complete rotation of the comet. Aims: We aim to characterize the spatial distribution of dust, H...

On 2015 July 18, near perihelion at a heliocentric distance of 1.28 au, the Visible InfraRed Thermal Imaging Spectrometer (VIRTIS-M) on board the Rosetta spacecraft had the opportunity of observing dust activity in the inner coma with a view of the night side (shadowed side) of comet 67P/Churyumov-Gerasimenko. At the time of the measurements we pre...

The Rosetta/ESA spacecraft followed the comet 67P/Churyumov-Gerasimenko from 2014 August (3.6 au pre-perihelion) to 2016 September (3.6 au post-perihelion). This offered a unique opportunity to analyze the time evolution of the dust properties in the inner coma. Onboard Rosetta, the Visual Infrared and Thermal Imaging Spectrometer (VIRTIS-M) acquir...

On 27 Apr 2015, when 67P/C-G was at 1.76 au from the Sun and moving towards perihelion, the OSIRIS and VIRTIS-M instruments on Rosetta observed the evolving dust and gas coma during a complete rotation of the comet. We aim to characterize the dust, H2O and CO2 gas spatial distribution in the inner coma. To do this we performed a quantitative analys...

We analyze 2–5 μ m spectroscopic observations of the dust coma of comet 67P/Churyumov-Gerasimenko obtained with the Visible InfraRed Thermal Imaging Spectrometer (VIRTIS-H) instrument on board Rosetta from 3 June to 29 October 2015 at heliocentric distances rh = 1.24–1.55 AU. The 2–2.5 μ m color, bolometric albedo, and color temperature were measur...

We analyze 2-5 micrometre spectroscopic observations of the dust coma of comet 67P/Churyumov-Gerasimenko obtained with the VIRTIS-H instrument onboard Rosetta from 3 June to 29 October 2015 at heliocentric distances r_h = 1.24-1.55 AU. The 2-2.5 micrometre color, bolometric albedo, and color temperature are measured using spectral fitting. Data obt...

We present an analysis of transient events observed by the Visible InfraRed Thermal Imaging Spectrometer, instrument aboard Rosetta, for the dates of 2015 August 10, September 13 and 14, during the two months surrounding the comet perihelion passage of the Rosetta spacecraft. We detected and characterized events with life-times ranging from 26 min...

ESA's Rosetta spacecraft had the unique opportunity to be in the vicinity of comet 67P/Churyumov-Gerasimenko for 2.5 years, observing the regions of the coma within a few km of the surface and to study the dynamical and physical properties of the emitted dust. In this work, we will present a summary of the dust coma investigations during the pre-pe...

This is a review of current knowledge about Earth’s nearest planetary neighbour and near twin, Venus. Such knowledge has recently been extended by the European Venus Express and the Japanese Akatsuki spacecraft in orbit around the planet; these missions and their achievements are concisely described in the first part of the review, along with a sum...

An investigation is presented of the dust scattering in the coma of 67P/Churyumov-Gerasimenko for the dates of 2015 February 28, March 15, and April 27. Comparison of the morphology of dust continuum maps at 1.1 μm and gas emission shows that for the above dates the spatial distribution of the dust is strongly correlated with H2O but not with CO2 e...

Rosetta observes sublimating surface ices Comets are “dirty snowballs” made of ice and dust, but they are dark because the ice sublimates away, leaving some of the dust behind on the surface. The Rosetta spacecraft has provided a close-up view of the comet 67P/Churyumov-Gerasimenko as it passes through its closest point to the Sun (see the Perspect...

On 9-10 of April 2016, the Rosetta orbiter completed a close flyby around the nucleus of 67P/Churyumov-Gerasimenko, when the comet was at heliocentric distance of 2.76 AU, along the outbound leg of its orbit around the Sun. This allowed the VIRTIS-M imaging spectrometer to observe the surface of 67P at visible wavelengths (0.2-1 μm) in the 0.93°-89...

On 9-10 of April 2016, the Rosetta orbiter completed a close flyby around the nucleus of 67P/Churyumov-Gerasimenko (CG), when the comet was at heliocentric distance of 2.76 AU, along the outbound leg of its orbit around the Sun. This allowed the VIRTIS imaging spectrometer to observe the surface of CG at visible wavelengths (0.2-1 µm) in the 0.93°-...

On 13 September, 2015, the Visual, Infrared and Thermal Imaging Spectrometer (VIRTIS) onboard Rosetta observed strong, anomalous activity of the coma of 67P/Churyumov-Gerasimenko starting at 13:40 UTC, in a range of latitude between -26° and -40° and longitude between 265° and 280°. VIRTIS is an imaging spectrometer in the spectral range 0.25-1 mm...

The VIRTIS (Visible, Infrared and Thermal Imaging Spectrometer) instrument aboard the Rosetta spacecraft has performed extensive spectral mapping of the surface of comet 67P/Churyumov-Gerasimenko in the range 0.3–5 µm. The reflectance spectra collected across the surface display a low reflectance factor over the whole spectral range, two spectral s...

We present an investigation of the emission intensity of CO2 and H2O and their distribution in the coma of 67P/ Churyumov-Gerasimenko obtained by the VIRTIS-M imaging spectrometer on the Rosetta mission. We analyze 4 data cubes from Feb. 28, and 7 data cubes from April 27, 2015. For both data sets the spacecraft was at a sufficiently large distance...

In the period August 2014 - early May 2015 the heliocentric distance of the nucleus of 67P/CG decreased from 3.62 to 1.71 AU and the subsolar point moved towards the southern hemisphere. We investigated the IR spectra obtained by the Rosetta/VIRTIS instrument close to the newly illuminated regions, where colder conditions were present and consequen...

Context. Studying the coma environment of comet 67P/Churyumov-Gerasimenko (67P) is one of the primary scientific goals of the VIRTIS experiment on the ESA Rosetta mission. Aims. The distribution and variability of water vapour and carbon dioxide in the comet's coma are needed to estimate their production rate, abundances in the nucleus, and the spa...

Although water vapour is the main species observed in the coma of comet 67P/Churyumov-Gerasimenko and water is the major constituent of cometary nuclei, limited evidence for exposed water-ice regions on the surface of the nucleus has been found so far. The absence of large regions of exposed water ice seems a common finding on the surfaces of many...

Context. Outgassing from cometary nuclei involves complex surface and subsurface processes that need to be understood to investigate the composition of cometary ices from coma observations. Aims. We investigate the production of water, carbon dioxide, and carbon monoxide from the nucleus of comet 67P/ChuryumovGerasimenko (67P). These species have d...

The VIRTIS (Visible, Infrared and Thermal Imaging Spectrometer) instrument on board the Rosetta spacecraft has provided evidence of carbon-bearing compounds on the nucleus of the comet 67P/Churyumov-Gerasimenko. The very low reflectance of the nucleus (normal albedo of 0.060 ± 0.003 at 0.55 micrometers), the spectral slopes in visible and infrared...

Venus possesses a dense, hot atmosphere, composed primarily of carbon dioxide. A surface pressure of nearly 100 bars sustains the mean surface temperature of 740 K, which is essentially globally uniform except for topographic effects. The surface is totally hidden at visible wavelengths by multiple cloud decks extending from about 48 km altitude to...

Venus is the brightest 'star' in the night sky and it has been observed since ancient times. Often dubbed Earth's 'twin', it is the planet most similar to the Earth in size, mass and composition. There the similarity ends: Venus is shrouded by a dense carbon dioxide atmosphere, its surface is dominated by thousands of volcanoes and it lacks a prote...

The aim of this project is to characterise volcanism on Venus and its long-term effects on Venus’ climate and planetary evolution. Analyses of radar data, mathematical modelling, and laboratory experiments will be implemented in the investigation.

We emphasize the importance of treating Jupiter, its satellites and its magnetosphere as a system of mutual interactions and present a case for the multi-disciplinary investigation of that system. We point out (in a necessarily superflcial way) the need for further measurements of

The Visible, InfraRed, and Thermal Imaging Spectrometer (VIRTIS) on Rosetta obtained hyperspectral images, spectral reflectance maps, and temperature maps of the asteroid 21 Lutetia. No absorption features, of either silicates or hydrated minerals, have been detected across the observed area in the spectral range from 0.4 to 3.5 micrometers. The su...

Spacecraft studies of the three terrestrial planets with atmospheres have made it possible to make meaningful comparisons that shed light on their common origin and divergent evolutionary paths. Early in their histories, all three apparently had oceans and extensive volcanism; Mars and Earth, at least, had magnetic fields, and Earth, at least, had...

Forty years after a similar retrospective on ozone research at Oxford by Dobson in 1968, a review and synthesis is presented of the scientific and technological advances that were possible during the period from 1970 to 2010 as a result of the deployment of a number of innovative instruments on meteorological satellites by a research group in the A...

The first Martian year and a half of observations by the Mars Climate Sounder aboard the Mars Reconnaissance Orbiter has revealed new details of the thermal structure and distributions of dust and water ice in the atmosphere. The Martian atmosphere is shown in the observations by the Mars Climate Sounder to vary seasonally between two modes: a symm...

Planetary meteorologists seek to understand the origin and evolution of the family of planets that orbit the Sun, to investigate the stability of their atmospheres and to compare the surface environment and climate with the Earth. The radiative, dynamical and chemical processes in Earth's atmosphere all have analogues on the other planets: by study...

We provide a revised Table 5 for the paper by Nixon et al. [Appl. Opt. 48, 1912 (2009)], in which the abundances of 13CO2 and C18O were incorrect.

Since arriving at Venus in April 2006 Venus Express has provided a wealth of information on a large variety of topics on the atmosphere, surface and plasma environment of the planet. The atmosphere in the southern hemisphere has been studied in detail by three instruments dedicated to atmospheric investigations, from the near IR to the UV and addit...

The new knowledge that has been acquired about Venus since the publication of the books Venus I (1982) and Venus II (1997) will form the basis for a new volume, Venus III in 2013/14. Although stimulated by Venus Express, and timed to incorporate results from the Japanese Akatsuki mission, contributions from any source including theory, models, and...

Near-infrared spectra from the Visible and Infrared Thermal Imaging Spectrometer (VIRTIS) on Venus Express have been used to investigate the vertical structure and global distribution of cloud properties on Venus. The spectral range covered by VIRTIS is sensitive on the nightside to absorption by the lower and middle cloud layers, which are back-li...

Watering the Moon About a year ago, a spent upper stage of an Atlas rocket was deliberately crashed into a crater at the south pole of the Moon, ejecting a plume of debris, dust, and vapor. The goal of this event, the Lunar Crater Observation and Sensing Satellite (LCROSS) experiment, was to search for water and other volatiles in the soil of one o...

Since April 2006 Venus Express has been performing a global survey of the remarkably dense, cloudy, and dynamic atmosphere of our near neighbour. A consistent picture of the climate on Venus is emerging on the basis of the new data, which enables us to provide an overview of the global temperature structure, the composition and its variations, the...

The Rosetta spacecraft accomplished a flyby of Mars on its way to 67P/Churyumov-Gerasimenko on 25 February 2007. In this paper we describe the measurements obtained by the M channel of the Visual and Infrared Thermal Imaging Spectrometer (VIRTIS-M) and the first scientific results derived from their analysis. The broad spectral coverage of the VIRT...

1] Past spacecraft observations of Venus have found considerable spatial and temporal variations of water vapour abundance above the clouds. Previous searches for variability below the clouds at 30– 45 km altitude found no large scale latitudinal gradients, but lacked the spatial resolution to detect smaller scale variations. Here we interpret resu...

The Venus Express mission, currently orbiting Earth's nearest planetary neighbour, has just had its mission extended until the end of 2012 by the European Space Agency (ESA). In December 2010 it will be joined by the Japanese Venus Climate Orbiter, which has similar goals of understanding the atmosphere and climate. In this article Fred Taylor look...

Since April 2006 Venus Express has been performing a global survey of the remarkably dense, cloudy, and dynamic atmosphere of our near neighbour. A consistent picture of the climate on Venus is emerging on the basis of the new data on the global temperature structure, the com-position and its variations, the cloud morphology at various levels, the...

Since April 2006 Venus Express has been performing a global survey of the remarkably dense, cloudy, and dynamic atmosphere of our near neighbour. A consistent picture of the climate on Venus is emerging on the basis of the new data, which enables us to provide an overview of the global temperature structure, the composition and its variations, the...

Part I. Views of Mars, From the Beginning to the Present Day: 1. The dawn of Mars exploration; 2. The first space missions to Mars; 3. After Viking: the 20-year hiatus; 4. The modern era; Part II. The Big Science: Motivation to Continue the Quest: 5. The origin and evolution of planet Mars; 6. The changing climate of Mars; 7. The search for life; P...

The Mars Climate Sounder (MCS) onboard the Mars Reconnaissance Orbiter is the latest of a series of investigations devoted to improving the understanding of current Martian climate. MCS is a nine-channel passive midinfrared and far-infrared filter radiometer designed to measure thermal emission in limb and on-planet geometries from which vertical p...

Venus Express now approaches the end of its first extended mission, having been in Venus orbit since early 2006. The VIRTIS instrument, which covers a wavelength range between 0.25 to 5.1 mum, has been continually measuring nightside thermal emissions from the deep atmosphere between 1.0 and 2.5 mum. Absorption bands of CO, H2O and OCS in this regi...

A fast method is presented for deriving the tropospheric CO concentrations in the Venus atmosphere from near-infrared spectra using the night side 2.3 μm window. This is validated using the spectral fitting techniques of Tsang et al. [Tsang, C.C.C., Irwin, P.G.J., Taylor, F.W., Wilson, C.F., Drossart, P., Piccioni, G., de Kok, R., Lee, C., Calcutt,...

We present radiative transfer modelling of thermal emission from the nightside of Venus in two ‘spectral window’ regions at 1.51 and 1.55 μm. The first discovery of these windows, reported by Erard et al. [Erard, S., Drossart, P., Piccioni, G., 2009. J. Geophys. Res. Planets 114, doi:10.1029/2008JE003116. E00B27], was achieved using a principal com...

Venus Express is the first European (ESA) mission to the planet Venus. Its main science goal is to carry out a global survey of the atmosphere, the plasma environment, and the surface of Venus from orbit. The payload consists of seven experiments. It includes a powerful suite of remote sensing imagers and spectrometers, instruments for in-situ inve...

The processes in the atmosphere, interior, surface, and near-space environment that together maintain the climate on Venus are examined from the specific point of view of the advances that are possible with new data from Venus Express and improved evolutionary climate models. Particular difficulties, opportunities, and prospects for the next genera...

[1] Observations of Venus' mesosphere by the Visible and Infrared Thermal Imaging Spectrometer (VIRTIS)-M instrument of Venus Express have been used to investigate the spatial distribution of CO above Venus' nightside cloud tops by fitting the CO absorption in the (1-0) CO band around 4.7 μm. We find little spatial variation in the abundance of CO...

The composite infrared spectrometer (CIRS) instrument on board the Cassini Saturn orbiter employs two 1 × 10 HgCdTe detector arrays for mid-infrared remote sensing of Titan’s and Saturn’s atmospheres. In this paper we show that the real detector spatial response functions, as measured in ground testing before launch, differ significantly from ideal...

The first systematic observations of the middle atmosphere of Mars (35–80km) with the Mars Climate Sounder (MCS) show dramatic patterns of diurnal thermal variation, evident in retrievals of temperature and water ice opacity. At the time of writing, the data set of MCS limb retrievals is sufficient for spectral analysis within a limited range of la...

A summary of recent progress in understanding climate evolution on Venus with an emphasis on Venus Express results.

The Diviner Lunar Radiometer Experiment on NASA’s Lunar Reconnaissance Orbiter will be the first instrument to systematically map the global thermal state of the Moon and its diurnal and seasonal variability. Diviner will measure reflected solar and emitted infrared radiation in nine spectral channels with wavelengths ranging from 0.3 to 400 micron...

When seen in ultraviolet light, Venus has contrast features that arise from the non-uniform distribution of unknown absorbers within the sulphuric acid clouds and seem to trace dynamical activity in the middle atmosphere. It has long been unclear whether the global pattern arises from differences in cloud top altitude (which was earlier estimated t...

Abstract Available from http://www.agu.org

ABSTRACT

Venus Express is carrying six instruments dedicated to the study of the atmosphere of Venus and the interaction of the atmosphere with both the solar wind and the planetary surface. The spacecraft is orbiting in a highly elliptic polar orbit with an apocentre 66000 km above the South Pole and a pericentre about 250 km above the North Pole. The firs...

The Mars Climate Sounder (MCS) has obtained measurements of the Martian atmosphere for one Mars year. Onboard the Mars Reconnaissance Orbiter (MRO), MCS continues to acquire high vertical resolution profiles of temperature, dust, condensates of CO2 and H2O, and water vapor by observing the limb of the atmosphere from the surface to 80 km in the spe...

1] An analysis of near-infrared emissions on the nightside of Venus observed by the Visible and Infrared Thermal Imaging Spectrometer (VIRTIS) instrument on board Venus Express reveals anomalous cloud particles in the polar regions of Venus. These anomalous particles are found within the centers of polar vortices at both poles and are either larger...

Current understanding of weather, climate and global atmospheric circulation on Mars is incomplete, in particular at altitudes above about 30 km. General circulation models for Mars [1,2,3,4,5,6] are similar to those developed for weather and climate forecasting on Earth and require more martian observations to allow testing and model improvements....

We present nightside observations of tropospheric carbon monoxide in the southern hemisphere near the 35 km height level, the first from Venus Express/Visible and Infrared Thermal Imaging Spectrometer (VIRTIS)-M-IR. VIRTIS-M data from 2.18 to 2.50 μm, with a spectral resolution of 10 nm, were used in the analysis. Spectra were binned, with widths r...

Observations of Venus' mesosphere by the VIRTIS-M instrument of the Venus Express spacecraft have been used to investigate the spatial distribution of CO above Venus' night side cloud tops by fitting the CO absorption in the (1-0) CO band around 4.7 μm [1]. Estimates of the CO abundance above the cloud tops have also been made using Venus Express S...

We present zonal and meridional wind measurements at three altitude levels within the cloud layers of Venus from cloud tracking using images taken with the VIRTIS instrument on board Venus Express. At low latitudes, zonal winds in the Southern hemisphere are nearly constant with latitude with westward velocities of 105 ms-1 at cloud-tops (altitude...

Titan: Exploring an Earthlike World presents the most comprehensive description in book form of what is currently known about Titan, the largest satellite of the planet Saturn and arguably the most intriguing and mysterious world in the Solar System. Because of its resemblance to our own planet, Titan is often described as a "frozen primitive Earth...

Context. Airglow emissions, such as previously observed from NO and O (0-0) on Venus, provide insight into the chemical and dynamical processes that control the composition and energy balance in the upper atmospheres of planets. The OH airglow emission has been observed previously only in the Earth's atmosphere where it has been used to infer atomi...

We present a correlated-k-based model for generating synthetic spectra in the near-infrared window regions, from 1.0 to 2.5 μm, emitted from the deep atmosphere of Venus on the nightside. This approach is applicable for use with any near-infrared instrument, ground-based and space-borne, for analysis of the thermal emissions in this spectral range....

As our own planet gets ever more crowded and its natural resources used up, it would be nice to know there was a "back-up" Earth not too far away: a place with pristine forests and deserts, tropical temperatures and vast, unpolluted oceans. Until quite recently it seemed that there was, for this was our vision of Venus – our nearest neighbouring pl...

Mid-infrared spectra measured by Cassini's Composite InfraRed Spectrometer (CIRS) between July 2004 and January 2007 (L s = 293 • –328 •) have been used to determine stratospheric temperature and abundances of C 2 H 2 , C 3 H 4 , C 4 H 2 , HCN, and HC 3 N. Over 65,000 nadir spectra with spectral resolutions of 0.5 and 2.5 cm −1 were used to probe s...

Since April 2006 the ESA's Venus Express mission carries out complex programme of global remote sensing and in-situ observations of the Venus atmosphere, the surface, and the plasma environment. The spacecraft provides seven experiments a versatile platform to perform various kinds of science operations including nadir and limb observations, stella...

We observed a stellar occultation by Titan on 2003 November 14 from La Palma Observatory using ULTRACAM with three Sloan filters: u′, g′, and i′ (358, 487, and 758 nm, respectively). The occultation probed latitudes 2° S and 1° N during immersion and emersion, respectively. A prominent central flash was present in only the i′ filter, indicating wav...

Mars Climate Sounder (MCS) on board NASA's Mars Reconnaissance Orbiter (MRO) primarily operates as a limb sounding infrared radiometer. The small field of view and limb scanning mode allow retrieval of atmospheric temperature and dust properties from the surface up to approximately 80km with 5km vertical resolution. The polar orbit of MRO gives cov...

Venus is Earth's near twin in mass and radius, and our nearest planetary neighbour, yet conditions there are very different in many respects. Its atmosphere, mostly composed of carbon dioxide, has a surface temperature and pressure far higher than those of Earth. Only traces of water are found, although it is likely that there was much more present...

Venus has no seasons, slow rotation and a very massive atmosphere, which is mainly carbon dioxide with clouds primarily of sulphuric acid droplets. Infrared observations by previous missions to Venus revealed a bright 'dipole' feature surrounded by a cold 'collar' at its north pole. The polar dipole is a 'double-eye' feature at the centre of a vast...