Cy Twombly, René Magritte and Thomas Struth – the week in art

Jonathan Jones's top shows this week Thomas Struth: Photographs 1978-2010 When is a documentary photograph not a documentary photograph? When it's by Thomas Struth . The German artist's epic studies of people marvelling at sites of such profound cultural value as the Pantheon in Rome cause you to wonder what these places mean to their modern visitors. • At Whitechapel Art Gallery, London, until 16 September The Cult of Beauty: The Aesthetic Movement 1860–1900 Seize the last chance to see the best London exhibition of the year so far, a subversive visual essay on the true nature of our ancestors – the Victorians. Nineteenth-century British artists, designers, and writers are revealed as radical hedonists whose luxuriant worldview helped to shape the modern imagination . • At V&A museum, London, until 17 July Urs Fischer and Georg Herold The most compelling works at this year's Venice Biennale are life-size wax sculptures by Urs Fischer which, you come to realise, are actually slowly melting giant candles. Here Fischer collaborates with German sculptor Georg Herold in a two-man show with an equally surprising twist – there is a life model present in the gallery at all times. • At the Modern Institute, 14-20 Osborne Street, Glasgow, until 3 September Devotion by Design: Italian Altarpieces before 1500 Many paintings that we look at in art museums were once part of carved wooden multi-panel altarpieces. In this free exhibition, the National Gallery recreates the original contexts of some of its oldest paintings so that they are shown as they were meant to be seen. • At the National Gallery, London, 6 July to 2 October René Magritte: The Pleasure Principle One of the true modern greats, René Magritte fascinates because he so poignantly questions the power of painting to create illusions. With irony and finesse, his works portray objects and spaces with a deadpan realism that is undermined by sheer impossibilities. • At Tate Liverpool until 16 October Up close: artworks in detail Simone Martini, Christ Discovered in the Temple, 1342 If you are heading to the Magritte exhibition at Tate Liverpool it is worth a detour to the city's outstanding Walker Art Gallery to see this masterpiece of medieval art. Simone Martini rose to fame in 14th-century Siena as an artist of sinuous beauty, and his celebrity took him to Avignon (home of the schismatic Pope at the time), where he painted this gorgeous work. It is a very rare survival of his Avignon works and contemporary with his lost portrait of Laura, the beauty to whom the poet Petrarch wrote hundreds of verses. One of the most important medieval paintings in Britain. • At Walker Art Gallery, Liverpool Francis Picabia, Fille née sans mere (Girl born without a mother), about 1916-17 An eerie prophesy of our digital age, created a century ago. In the years before and during the first world war artists were fascinated and spooked by the idea of humans as machines. Picabia's techno-child is one of the most compelling of these science fiction modernist images, along with Jacop Epstein's Rock Drill and Marcel Duchamp's Bride Stripped Bare by her Bachelors, Even. • At Dean Gallery, Edinburgh Henry Moore, Standing Figure: Knife Edge, 1961 If visiting the popular new Hepworth gallery in Wakefield you should also treat yourself to a stroll around nearby Yorkshire Sculpture Park where, among a huge variety of modern sculptures set in rolling green spaces, the works of Henry Moore are particularly impressive. This towering yet whimsical figure and other organic forms by Moore take on a dreamlike quality against grass and sky. Is Moore a truly great sculptor or a soft imitator of Picasso? In the Yorkshire landscape, Standing Figure has a romantic character that argues powerfully for the former. • At Yorkshire Sculpture Park Andy Warhol, Jacqueline, 1964 A Warhol portrait of Blondie's Deborah Harry recently sold for several millions , yet this moving image of Jackie Kennedy at President John F Kennedy's funeral is a far more powerful work from Warhol's most creative years. You can see it, for free, in a Midlands public collection. Warhol claimed he was left cold by the assassination of JFK, but his portraits of Jackie in mourning ache with the pain and rage of a nation bereft. • At Wolverhampton Art Gallery GF Watts, Paolo and Francesca, 1872-75 George Frederic Watts was a Victorian symbolist, whose paintings shared with contemporary European artists an urge to dig below the surface and illuminate the world of imagination. This painting of doomed lovers from Dante's Inferno is in the collection of his works at the Watts Gallery . It explores the same intense imagery of death and desire as French artists such as Moreau and Redon, and is a rich insight into the mythic ambitions of 19th-century British art. • At Watts Gallery, Compton, Surrey What we learned this week The real reason Habitat went bankrupt Exactly why artists think Cy Twombly was a knockout Why no one will pony up for Mark Wallinger's giant horse sculpture Why Hipstamatic became the weapon of choice for photojournalists in Afghanistan Final proof that Hollywood has always been heavenly Image of the week Your Art Weekly What exhibitions are you going to see this week? Have you been to any of these shows? Did you agree with our reviews? Give your review in the comments below or tweet us your verdict using #artweekly and we'll publish the best ones next week. Follow us on Twitter Like us on Facebook