When will the Sun stop working?

The Sun is a massive nuclear fusion reactor that is converting hydrogen to helium and releasing vast quantities of energy as result. This means that eventually it will run out of fuel and cease producing energy. When that happens there will be no possibility of life continuing on any planet in the solar system. So how long have we got?


We’re all doomed!

All good things must come to an end, and that means that not only will every person, animal and plant currently alive have to “meet its maker” (however you might interpret that expression), but even the Sun itself will eventually die and cease to emit light and heat.

However, there is no need to panic! The Sun has been going strong for 4.6 billion years and will continue to do so for a long time yet.

What will happen, over the next few billion years, is that as the Sun’s nuclear fuel is gradually used up it will become both brighter and bigger - twice as bright and 50% larger.

Around five billion years from now all the hydrogen in the Sun will have been converted to helium and the nuclear fusion process will end. The core will shrink and the outer layers expand massively while at the same time becoming much cooler. The Sun will have become a red giant.

The diameter of the Sun will expand to such an extent that it will swallow up the inner planets, including Earth. However, life on this planet will have become impossible long before this point is reached – even if mankind has not committed collective suicide (on behalf of all living things) many millions of years before this happens.

Eventually the Sun’s outer layers will fade away into space, to leave only a small white dwarf star behind. If the Sun had been considerably more massive at the outset it would have run the risk of exploding as a supernova, but it was never anywhere close to being that category of star.

The total life of the Sun, from birth to death as a fading white dwarf, will have been about 11 billion years, of which the existence of humankind on Earth will have been an extremely small fraction.

At least – when it happens – nobody will be able to blame any President or Prime Minister of the “wrong” political persuasion for their lack of action in allowing the Sun to stop working!

© John Welford

Venus: Earth's fierce sister planet

Venus is the closest planet to Earth in terms of distances between orbits (about 41 million kilometres) and the two planets are quite similar in size, surface area, volume and mass. Venus is therefore sometimes dubbed Earth's sister planet.

However, the sisters have very different characteristics. For one thing, Venus rotates far more slowly than Earth, so that a day on Venus lasts longer than a Venusian year! It also rotates the other way round to Earth, so that the sun rises in the west and sets in the east.

However, the most important difference, and the main one that makes it impossible for life to exist there, or for manned missions ever to be contemplated, is that the surface temperature on Venus averages 450 degrees Celsius. Atmospheric pressure is also enormous, being 90 times as great as that on the surface of Earth.

The main reason for the huge surface temperature is the fact that the Venusian atmosphere consists of 96% carbon dioxide, thus causing the thick cloud cover of Venus to act like extremely efficient greenhouse glass. Temperatures on Venus are therefore 100 degrees hotter than on Mercury, which is closer to the sun by about 50 million kilometres.

It has often been said that Earth risks becoming another Venus if the proportion of greenhouse gases in the atmosphere is allowed to keep rising. However, with carbon dioxide currently representing 0.4% of Earth's atmosphere it clearly has a long way to go before reaching the Venusian level!

© John Welford

Vincent Van Gogh injures himself, December 1888

On 24th December 1888 occurred one of history’s best-known acts of self-mutilation, namely the severing of part of his ear by the Dutch artist Vincent Van Gogh.

Van Gogh had settled in the town of Arles in southern France, where, in February of that year, he had hoped to start a community of like-minded artists. However, nobody else was willing to abandon Paris to join him and it was only when Vincent’s brother Theo offered to pay his train fare that one artist, Paul Gauguin, was persuaded to go south. Theo knew just how mentally unstable Vincent was, and he feared for the consequences if Vincent was left on his own.

To start with, the two artists struck up a relationship and they lived and painted together for two months. However, Gauguin then came to realise that the differences between them were greater than the similarities and he sought to bring the arrangement to an end.

Van Gogh was extremely distressed by this prospect and became violent towards Gauguin. Things came to a head on Christmas Eve when he attacked Gauguin with a razor, although he failed to wound him. It was after this that he shut himself away and used the razor to cut off part of his ear. It was apparently his intention to give it to his favourite prostitute as a somewhat bizarre Christmas present.

Paul Gauguin left the following day and the two artists never saw each other again. Gauguin settled in Brittany before going even further away – to Tahiti and the Marquesas Islands in the South Pacific. Vincent Van Gogh did not stay in Arles for much longer before committing himself to a mental asylum and then returning to Paris, where he shot himself in July 1890. It was a sad end for a tormented genius.

© John Welford

Clues to life on Mars from the Atacama Desert

The idea that there might once have been living organisms on Mars is a fascinating one, and even more so is the notion that some form of very primitive life might still be there. However, clues as to where the evidence for past or present life could be found are coming from a very strange direction, namely studies of the Atacama Desert in Chile, South America.

The Atacama Desert is one of the driest places on Earth and thus offers a reasonably close parallel to conditions on Mars – or at least to Mars as it might have been in fairly recent geological time.

The point is that microbes – very simple life forms – can survive for many years in water-free environments and reactivate when water again becomes available. This has been shown to happen in the Atacama Desert, where microbes survive in a dormant state in salt crusts (see picture) that absorb any water that happens to be around. This need not even be liquid water, because salt can take water directly from the air.

The question is therefore whether similar conditions could exist on Mars, given that it is known that there was once abundant liquid water on the planet that could have given rise to salt deposits as it evaporated. Indeed, such deposits have been discovered in Mars’s southern uplands. Modern Mars is not totally devoid of water, although most of it exists as ice at the north polar cap and beneath the surface. There are also very small amounts of water vapour in the thin atmosphere of the planet.

Given the much drier conditions on Mars, it is conceivable that evolutionary processes might have worked differently than on Earth, such that lifeforms could have survived on Mars that would not have done so on Earth. It is therefore going to be very interesting for future rover missions to explore the salt deposits on Mars to see if primitive life has survived. If it can do so in the Atacama, there is a reasonable chance that this is also possible in comparable environments on Mars.

© John Welford

Tintoretto, a great but crafty Venetian artist

The name “Tintoretto” was a nickname, meaning “the little dyer” or “the son of the dyer” which was given to Jacopo Robusti (c.1519-1594) because he was the eldest of the 21 children of a Venetian dyer of silk cloth.

His father took note of Jacopo’s talent for painting at an early age. The boy had a penchant for daubing pigments on the wall of his father’s workshop in ways that were more creative than the sort of behaviour that might normally lead to a clip round the ear in such circumstances, and so, when he was about 14, his father sent him to the artist Titian (then aged 56) to see if he could be trained to make the best use of his skills.

The story goes that Titian sent him home after only ten days in his studio, on the grounds that the work Tintoretto was producing was so much better than that of his master that Titian grew jealous and refused to have him around. This is unlikely to be the real explanation, and it is far more likely that Titian recognised that the young man’s independent style was such that he had little to teach him. Tintoretto was therefore largely self-taught.

Whether or not Tintoretto regarded his treatment by Titian as a rebuff, it is clear that the two men did not get on well. Artists of the day depended on winning commissions from wealthy patrons, and Titian was out to win as many high-paying commissions as he could get. Tintoretto realised that he could get work by offering to do it for less than Titian demanded. This was hardly likely to endear Tintoretto to the older artist, or indeed to other Venetian artists on whom he pulled the same trick.

Another reason for Tintoretto’s success as an artist is that he was extremely reluctant ever to leave the city of Venice, and he was therefore on the spot when commissions came up, whereas Titian travelled all over Europe to work for foreign monarchs, the Church, and other patrons.

Tintoretto was thus able to have a successful and lucrative career as a Venetian portrait painter. Venice was at the height of its commercial and political power during the 16th century and there were many noblemen and wealthy merchants who were anxious to be immortalized in oils.

In 1550 Tintoretto married the daughter of a Venetian nobleman. The couple were very close, even to the extent that Tintoretto hated to be parted from her for more than a day at a time. It is probably also true that she wanted to keep a close eye on him. On the only occasion when Tintoretto is known to have left Venice, at the age of 62, he insisted that his wife accompany him to visit the court of the Gonzaga family at Mantua.

Tintoretto was able to work extremely quickly when the occasion demanded and this ability, together with his quick wits and opportunistic nature, stood him in very good stead when a major commission was announced, in 1564, for the decoration of the interior of the Scuola (Brotherhood) di San Rocco, a building next door to the church of San Rocco in Venice.

Four painters, including Tintoretto, were invited to present designs for the central roundel of the ceiling, which would then be considered by the committee of the Brotherhood. While the other three painters went away to work on their designs, Tintoretto measured the space in question, painted a canvas in double-quick time, and stuck the result in place. When the committee (and the other artists) protested, Tintoretto offered to give the painting to the Brotherhood for no fee. As their policy was never to turn down a gift, they had no choice but to accept it and, having done so, felt honour bound to give Tintoretto the rest of the commission, which he continued to work on for the next 24 years, including major works in the church next door.

Tintoretto’s other major work was on the Doges’ Palace, which had suffered fires in 1574 and 1577 and which was therefore in need of re-decoration. Tintoretto worked alongside Paolo Veronese (who, as his nickname suggests, was an “import” from Verona). Veronese had worked in the palace in 1553 when he first arrived in Venice, and he did not always appreciate having to share the work (and the fees) with the troublesome Tintoretto, especially after he had been robbed of a commission when the latter had offered to paint a work in Veronese’s style, at a lower fee than Veronese would have charged.

Tintoretto’s greatest and final contribution to the palace restoration was a painting on canvas entitled “Paradise” (1592). It is widely believed to be the largest painting ever done on canvas, measuring 75 feet by 30 feet. It includes hundreds of figures, many of which were painted from life. Tintoretto worked on this with his son Domenico, who was nothing like as talented as his father, and the painting’s lack of Tintoretto’s typical skill in depicting light and space might be due to that fact.

Tintoretto’s style owed much to what is termed Mannerism, which contrasted with both High Renaissance style and Baroque. The term is often used derogatively, to indicate a falling off from the classical perfection of the Renaissance towards an emphasis on structure at the expense of naturalism. Thus limbs might be extended to unnatural lengths or figures placed in strange positions if that suited the artist’s conception of how the painting should be structured.

If Tintoretto’s works sometimes appear “stagey” there is a very good reason for that. He often designed a work by making model figures out of wax that could be twisted into the desired shapes and placed on a board, with flying figures suspended from wires. He would therefore produce something that looked like a stage set from a model theatre, complete with lighting effects, and he would then paint what he saw.

Tintoretto’s use of light had a lot to do with living in Venice. It was customary for heavy shutters to be used to shield inhabitants from the bright Italian sun, but the light that entered rooms would then be diffuse and often be bounced up from the water of Venice’s many canals. This meant that the colours that Tintoretto saw and reproduced would glow but be muted, such as dull gold, crimson, mulberry and sea green, and there would only rarely be a direct light source. The overall effect is fluid and dreamlike, but without the physical immediacy that one associates with Titian.

Tintoretto died on 31st May 1594. He was buried alongside his daughter Marietta who had inherited some of her father’s talent as an artist but had died in 1590 aged about 30. Tintoretto’s name lives on as that of one of the greats of Italian post-Renaissance art. 

© John Welford

Where do fast radio bursts come from?

Astronomers are constantly finding new and mysterious things “out there”, and cosmologists then expend considerable energy on working out what they are!

One of the latest phenomena in this category is the “fast radio burst” or FRB, which is a pulse of radio waves that is extremely brief – a matter of fractions of a second. The first detection of an FRB was made in 2007, from examination of signals received in 2001 by the Parkes radio telescope in Australia. The pulse lasted for only 4.6 milliseconds (a millisecond is a thousandth of a second).

Despite much analysis of data received by radio telescopes across the world, only a handful of FRBs have been found to date, and only one (in 2014) has been observed as it happened.

Astronomers would love to be able to track an FRB to its source, and this can best be done by getting a number of radio telescopes in different countries to get a fix on a signal, once one has been detected. In April 2015 they were able to do this after an FRB was picked up that lasted for less than a millisecond. What they also discovered was that the burst produced a “radio afterglow” that continued for six days. This gave the astronomers at Parkes enough time to alert the Subaru telescope in Hawaii to focus on the source, which in turn led to the discovery that the signal came from an elliptical galaxy some 7 billion light years away. The radio burst therefore started its journey several billion years before Planet Earth existed!

Various theories have been proposed to explain the cause of a fast radio burst, and – as might be expected – alien intelligence of some kind is on the list. However, the theory that is currently being given most weight is that FRBs originate from the collision of two neutron stars (a neutron star is the extremely small and dense residue of a collapsed giant star). Such an event would produce a massive amount of energy that would also include gravitational waves, such as are believed to result from the merging of black holes. It is hoped that a gravitational wave source will be confirmed as coinciding with that of a fast radio burst, but this has yet to happen.

However, not all cosmologists accept the idea that FRBs are caused by colliding neutron stars, or that there need be only one explanation. Another candidate is a flare from a magnetar, which is a neutron star with a powerful magnetic field, the decay of which can produce x-rays and gamma rays.

Speculation will doubtless continue until more observations can produce a more definitive answer to this particular problem.

© John Welford

Figure in a Landscape, by Francis Bacon

Francis Bacon (1909-92) was an artist whose work was not easy to like or to understand. He belonged to the Expressionist tradition, for which the purpose of art is not to depict the outside world but interior emotions, particularly those of fear, violence and alienation. His work was also heavily influenced by Surrealism, such that images of objects or faces are placed in “impossible” conjunction with each other.

Bacon was self-taught, relying on intuition as his master. His work was therefore highly original and distinctive, although disturbing and shocking to the viewer. Many of his best works were a response to the horrors of the mid-20th century, in which his figures are isolated in a terrifying, hostile environment. His canvases portray the frustration and brutality that afflicts the individual in a world that is increasingly difficult to cope with.

“Figure in a Landscape” dates from 1945, the year which marks Bacon’s rebirth as an artist. He had virtually given up painting in 1934, having been discouraged by his lack of commercial success, but felt inspired to release his angst with a series of paintings that attracted widespread notice and notoriety.

The figure is that of his friend Eric Hall (taken from a photograph), sitting the wrong way round on a seat in Hyde Park. However, this is not a portrait in the usual sense, because the figure has no head. The left side of the body is also missing, being replaced by a black hole in the shape of the man’s shoulders, which doubles as a tunnel in the sheer cliff behind the figure. The cliff is, not surprisingly, purely imaginary as there is no such feature in Hyde Park!

There are many other disturbing features in this painting, such as the man’s right leg that fades away into nothing, and his left leg which appears to have been consumed by maggots or beetles that stream away to the edge of the canvas.

It is not easy to work out what is happening on the right-hand side of the canvas, but it looks as though some sort of firearm has emerged from the tunnel, which is also the left half of the man, and it is being fired off to the right.

There is a bright blue sky at the top of the painting, above the cliff, but the rest is grey, black and brown. This is therefore a sinister, disturbing image, in which a man is being consumed by the landscape and taking part in the destruction that emerges from it.

Bacon painted this work during the last months of the Second World War, when Europe was being liberated and the horrors perpetrated by the Nazis were being brought to light. Bacon could have expressed hope for the future, but instead chose to portray the degeneracy at the heart of humanity that could allow such terrible things to happen.

It is an intensely depressing painting, but at the same time very powerful. Artists need to produce images of blackness and despair, for the simple reason that, if people do not understand the consequences of what they do, they are highly likely to go on doing the same things. Although one may find “Figure in a Landscape” nasty and repulsive, it is important that such works exist and can be seen. Only by looking at the dark side of the imagination can the viewer resolve to reject the impulses that lead human beings to make a reality of horrors such as this.

“Figure in a Landscape” can be seen at Tate Modern, London.

© John Welford

Ursa Major: a brief guide

Ursa Major is one of the most familiar constellations visible in the Northern Hemisphere. Here is a brief guide to some of its notable features.

Ursa Major (the Great Bear) is known by several names, including the Plough and the Big Dipper. It is an easily recognised constellation consisting of a rough rectangle and three other stars that appear to attach to it in a handle shape. These are the ones that are easily seen with the naked eye, but there are many more in this region of the night sky that can be seen with the aid of a telescope or binoculars.

As with all constellations, one has to remember that they are optical illusions in that their members usually have no relationship with each other and are at many different distances from Earth.

The two “outer” stars of the rectangle are Dubhe and Merak. These are known as the Pointers because an imaginary line drawn through them leads the eye to Polaris, the North Celestial Pole and a guide to finding one’s direction at night. Dubhe is a yellow giant star with high luminosity, being the 35th brightest star visible from Earth. It has a smaller companion star. Merak is a main sequence star that is nearly three times larger than our Sun and 68 times more luminous.

The second star in the “handle” is Mizar, although most people can soon make out that it is in fact two stars, the fainter companion being Alcor. However, Alcor is in fact a binary star and Mizar is a quadruple, which means that one is actually looking at six stars and not two.

If one has a good pair of binoculars it is possible to see two galaxies to the north of Ursa Major. These are Bode’s Galaxy (M81) and the Cigar Galaxy (M82). M82 is almost edge-on to us but M81 is tilted at a lesser angle. These galaxies are around 10 million light years away but close enough to each other to interact gravitationally.

The spiral galaxy M101 can be seen on the other side of the constellation. Binoculars will reveal it as a circular smudge but better magnification will show that it is a well-formed spiral that is face-on to us.

A good telescope can reveal the Owl Nebula (M97), although the “owl eyes” will need a relatively high resolution telescope in order to see them.

© John Welford

Van Gogh's changing colours

Art historians are discovering that one consequence of Vincent Van Gogh’s poverty is that many of his paintings do not look today as they did when he first painted them. In particular, many of his areas of red are gradually turning white.

Wealthier contemporary artists were able to use high-quality pigments in their paint, but Van Gogh lived a hand-to-mouth existence for most of his life, depending largely on the generosity of friends to keep him alive. When the urge to paint seized him, he had to use the cheapest materials that he could find.

For his red colours he used red lead, which is a pigment that has been known since ancient times. Unfortunately, when exposed to light the compounds in red lead that give it its colour break down to a mineral that reacts with carbon dioxide to produce two white-coloured compounds.

The degradation can be seen in Van Gogh’s 1889 “Wheat Stack Under a Cloudy Sky” (see above) in which floating leaves have changed from red to white.

Another problem has been noted with the purple-grey colouring in his “Head of an Old Woman with a White Cap” (1885). Vogh Gogh used a pigment based on cochineal, but this has now weathered to a greenish tinge.

Of course, nothing can change the artistry of Van Gogh’s work, and his genius can never be dimmed by a mere change of colour, but it has to be recognised that what we see in the world’s art galleries now is not what the artist saw when he first stepped back from the finished works.

© John Welford

Bennu, a near-Earth asteroid

Bennu is a ‘near-Earth’ asteroid, by which is meant a minor planet the orbit of which crosses that of Earth, as opposed to those in the asteroid belt between Mars and Jupiter. Astronomers are keen to keep a close watch on these asteroids, because there is a danger that one of them could collide with Earth, with potentially disastrous consequences for everything living here.

Bennu – the name comes from that of a heron-like bird in Egyptian mythology that may have provided the origin of the phoenix myth – is on the list of asteroids that offer a credible threat of collision. However, the chance has been estimated as being no worse than 1 in 1800 and the date of impact, should it occur, would not be until about the year 2180. It is only third on the list of ‘asteroids most likely to hit us’ but the other two are not expected to pose a threat any sooner than that of Bennu.

In the meantime, a mission is under way to have a good look at Bennu and see what it is made of. Given that it was formed from material that existed at the very beginning of the Solar System, knowledge of the asteroid’s composition is of considerable interest for understanding how the solar System evolved.

The mission will also be able to study precisely the course that Bennu takes in its orbit. This is clearly of fundamental importance in working out how the asteroid proceeds through space and the extent to which external forces, such as the solar wind, vary the orbit of small bodies such as this (Bennu has a diameter of 493 metres). Predicting future orbits is not easy with current knowledge, but precise information gathered from a close-up look will help to make computer models more accurate when future impact risks are being calculated.

The mission, called OSIRIS-Rex, was launched in September 2016 and is due to reach Bennu in 2018. The spacecraft will make readings of the surface for about eight months and enable a 3-D map to be created. From this map a landing site will be chosen so that a sample of rock can be taken from the surface, after which the craft will return to Earth. It is expected that the mission will conclude in 2023.

© John Welford

Frederick, Lord Leighton

Frederic Leighton was an artist who was immensely popular during his lifetime but who has fallen out of favour since his death. The modern viewer of his paintings and sculptures, which were mainly on subjects from Greek and Roman mythology, feels little sympathy for their stylised poses and waxen skin tones. However, to the Victorians, immersed as they were in the Classical revival that Leighton did much to create, they were all the rage.

Frederic Leighton was born in Scarborough on 3rd December 1830, the son of a physician, although he spent most of his early years abroad. When he was only ten years old he studied drawing in Rome and afterwards lived in Florence, where he was taught by several Italian artists. He later travelled to Brussels and Paris, where he continued his studies and copied pictures by Titian and Correggio in the Louvre, and in 1850 he moved to Germany and worked in Frankfurt for two years.

He then returned to Paris and set up a studio in the Rue Pigalle. It was from Paris that, in 1855, he sent a painting to the Royal Academy in London entitled “Cimabue’s Madonna Carried in Procession Through the Streets of Florence”. The painting created a sensation in London and was bought by Queen Victoria. British viewers greatly admired its elaborate design, precise drawing and fresh colours.

Leighton did not return to Britain for another five years, but when he did he was immediately lionised and received all the commissions he could handle for paintings in the same style, taking much from the example of the Renaissance masters in their handling of Classical themes. His reception by London society was greatly helped by his courtly manners and the charm of his personality.

He associated for a time with some of the Pre-Raphaelites, but was always too much of an “Establishment” figure to have much in common with artists of the temperament of D G Rossetti, for example. In any case, the Pre-Raphaelite Brotherhood of Rossetti, Holman Hunt and Millais had broken up by the time Leighton arrived back in England.

Among his most characteristic paintings were “The Daphnephoria” (now in the Lady Lever Art Gallery, Port Sunlight), “The Return of Persephone” (Leeds Art Gallery) and “The Bath of Psyche” (Tate Britain, London). These all display close attention to detail and attempts to recapture classical perfection as closely as possible. He was regarded by his contemporaries as having succeeded in this aim better than anyone else since Raphael.

Leighton is regarded by some (e.g. Charles Johnson in “English Painting”, 1934) as having been a better artist as a sculptor than as a painter. Among his best known sculptures are “The Sluggard” and “An Athlete Wrestling with a Python”, which are both in Tate Britain. These portray male nudes as ideal physiques and possess a certain degree of artificiality in the way that the subjects’ musculature is depicted.

The problem with his paintings, to a modern eye, is that they look more like portrayals of statues than of real people. Perfection of form is put ahead of any emotional content. One possible exception to this judgment is the above-mentioned “The Return of Persephone” in which the abducted queen of the underworld is released by Hades to signal the beginning of Spring. In Leighton’s painting (dated 1891) she has her arms outstretched as does her mother Demeter shortly before they will clearly meet in a warm embrace.

Leighton’s popularity with the art world and the general public can be assessed from the honours that were heaped upon him. He became a full Royal Academician in 1868 and President of the RA in 1878, when he was also knighted. He became a baronet in 1886 and the first Baron Leighton of Stretton in January 1896. He was therefore the first British painter to be elevated to the peerage.

However, he also had a less welcome claim to fame in that he died on 25th January 1896, the day after the patent confirming the peerage was issued. As he was unmarried and had no heirs, the title lapsed on his death, making the single day of its existence the shortest ever recorded for a British peerage.

The wide popularity of Frederic Leighton’s works, and those of followers such as Sir Edward Poynter and Sir Lawrence Alma-Tadema, can be attributed to the revival of interest in the classical world that began in the early years of Queen Victoria’s reign. At a time when the minds of the public were aroused by newspaper reports of discoveries in Greece, Egypt and elsewhere, it is not surprising that visitors to the Academy should have taken a liking to pictures that sought to portray life in classical times.

Whether the art of Lord Leighton will ever excite such interest again is a moot point, given that the emphasis in his works on physical perfection at the expense of feeling and movement runs counter to modern taste. His works can be studied as an insight to the Victorian mind, but that is probably as far as most people today would be willing to go.

© John Welford

Eris: the dwarf planet that demoted Pluto

Eris is a dwarf planet that, when discovered in 2005, was found to be larger than Pluto, which had been regarded as the Solar System’s ninth planet since its discovery in 1930. This posed huge question marks over Pluto’s right to that status, which has subsequently been removed.

Eris has an elliptical orbit that takes it from 38 AUs from the Sun at its closest to 97 AUs at its furthest point (AU stands for Astronomical Unit, one of which is the average distance of the Earth from the Sun). For comparison, Neptune is just over 30 AUs from the Sun and Pluto’s orbit varies from 30 AUs to 49 AUs.

Pluto’s orbit is almost wholly within the Kuiper Belt that consists of a vast number of small objects and is the source of most of the comets that visit the inner Solar System. However, Eris is considered to be a member of the “Scattered Disc” that extends beyond the Kuiper Belt as a diffuse outer halo. The orbit of Eris is not only highly elliptical but at an angle of 44 degrees from the plane of the Solar System within which the “regular” planets orbit. A complete orbit of the Sun by Eris takes around 560 years to complete.

Eris, which, at around 2390 kilometres, is believed to have a diameter about 200 kms larger than that of Pluto, is the second brightest object in the Solar System (the brightest is Enceladus, a moon of Saturn). This would appear to be because the surface is covered in frozen water and methane that are highly reflective of the Sun’s rays.

Eris has a moon of its own, named Dysnomia, which could be as large as 685 kms in diameter, which makes it a relatively large Scattered Disc / Kuiper Belt object in its own right. Calculations based on the orbit of Dysnomia around Eris enable a good estimate to be made of the mass of Eris, namely 27% greater than that of Pluto.

In Greek mythology Eris was the goddess of strife and discord, which seems appropriate given the upset caused to the status of Pluto from Eris’s discovery. Dysnomia was a daughter of Eris, her name meaning “lawlessness”.

© John Welford

Dining Room on the Garden, by Pierre Bonnard

Pierre Bonnard (1867-1947) qualified as a barrister in Paris in 1889 but his main interest was in art, having already enrolled in the Académie Julian in 1887. While there he was encouraged by Paul Sérusier to adopt a style of painting that used pure colour in flat areas with strong outlines, as developed by Paul Gauguin. Bonnard became a member of the “Nabis brotherhood” of painters (Nabi being Hebrew for “prophet”), led by Sérusier and which included Maurice Denis and Edouard Vuillard, that was devoted to this approach as an alternative to Impressionism.

Bonnard was also attracted to the simple formalism of Japanese art, which in turn led him to explore the possibilities of decorative art in media such as ceramics, furniture, fans, theatrical scenery and posters. It was Bonnard’s success in the last of these fields that inspired Henri de Toulouse-Lautrec to devote his energies in that direction.

The Nabis brotherhood split up in 1900, with Bonnard and Vuillard being less interested in the mystical and symbolist preoccupations of their fellow members. They preferred to concentrate on natural and domestic subjects for their art, and to incorporate Impressionist tendencies in their painting style. However, the Nabis use of areas of strong colour was a lasting legacy in their work.

Bonnard moved on to develop a style that made use of framing within his paintings, the frames being distinct vertical and horizontal lines that could be pieces of furniture, doors or window frames. He was very interested in the possibilities of photography, and the use of framing derived largely from that interest.

He moved to the south of France in 1910 and spent most of the rest of his life there. This move brought the importance of light and colour to his attention, with the greater intensity of the light in that region making the colours of all objects more vivid.

Bonnard painted “Dining Room on the Garden” in 1934-5, when he was a widely recognised and successful artist. It is a typical example of his mature style and his preferred subject matter, namely a domestic scene. In this case, the room is in a seaside villa where the artist and his family spent a summer.

Bonnard’s wife Marthe, who had formerly been his regular nude model, is pictured to the right of a window. She is dressed elegantly in dark brown clothes but her face is painted in a reddish-brown colour that is virtually identical to that of the wall behind her, so that she seems to fade into the background as being welded to the scene of domestic regularity. Her function is to form part of the frame in that she continues the upward line of a vase of red flowers, set on the table, which partially obscures her.

The focus of the painting is the window frame, with a thick central vertical division, through which can be seen part of the garden, two somewhat stylized trees, and the distant sea, above which is a bright blue Mediterranean sky.

Inside, the horizontal frame is provided by the table, with its pinkish-purple cloth, on which are various objects including a milk jug and fruit bowls.

The immediate impression given by the painting is of strong zones of colour that set each other in context. There is a vivid yellow patch, possibly of reflected sunlight, on the wall to the left of the window, which contrasts with the intense blue of the sky and the bright red of the table edge on the right-hand side. The early influence of Gauguin seems to have been maintained more than 30 years after the Nabis group members went their separate ways.

“Dining Room on the Garden”, with its strong lines and colours, speaks of order and stability. This is the work of an artist who is happy with his life and wants nothing more than to live out his days in the company of his devoted wife, in beautiful surroundings, and to have all the comforts of domestic life close to hand.

“Dining Room on the Garden” is in the Guggenheim Museum, New York.

© John Welford