White dwarf artwork
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Deprecated function: strtotime(): Passing null to parameter #1 ($datetime) of type string is deprecated in extra_body_classes_preprocess_html() (line 105 of modules/extra_body_classes/extra_body_classes.module).
extra_body_classes_preprocess_html(Array, 'html', Array)
call_user_func_array('extra_body_classes_preprocess_html', Array) (Line: 261)
Drupal\Core\Theme\ThemeManager->render('html', Array) (Line: 480)
Drupal\Core\Render\Renderer->doRender(Array, ) (Line: 240)
Drupal\Core\Render\Renderer->render(Array) (Line: 158)
Drupal\Core\Render\MainContent\HtmlRenderer->Drupal\Core\Render\MainContent\{closure}() (Line: 627)
Drupal\Core\Render\Renderer->executeInRenderContext(Object, Object) (Line: 159)
Drupal\Core\Render\MainContent\HtmlRenderer->renderResponse(Array, Object, Object) (Line: 90)
Drupal\Core\EventSubscriber\MainContentViewSubscriber->onViewRenderArray(Object, 'kernel.view', Object)
call_user_func(Array, Object, 'kernel.view', Object) (Line: 111)
Drupal\Component\EventDispatcher\ContainerAwareEventDispatcher->dispatch(Object, 'kernel.view') (Line: 186)
Symfony\Component\HttpKernel\HttpKernel->handleRaw(Object, 1) (Line: 76)
Symfony\Component\HttpKernel\HttpKernel->handle(Object, 1, 1) (Line: 58)
Drupal\Core\StackMiddleware\Session->handle(Object, 1, 1) (Line: 48)
Drupal\Core\StackMiddleware\KernelPreHandle->handle(Object, 1, 1) (Line: 28)
Drupal\Core\StackMiddleware\ContentLength->handle(Object, 1, 1) (Line: 32)
Drupal\big_pipe\StackMiddleware\ContentLength->handle(Object, 1, 1) (Line: 191)
Drupal\page_cache\StackMiddleware\PageCache->fetch(Object, 1, 1) (Line: 128)
Drupal\page_cache\StackMiddleware\PageCache->lookup(Object, 1, 1) (Line: 82)
Drupal\page_cache\StackMiddleware\PageCache->handle(Object, 1, 1) (Line: 48)
Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle(Object, 1, 1) (Line: 51)
Drupal\Core\StackMiddleware\NegotiationMiddleware->handle(Object, 1, 1) (Line: 36)
Drupal\Core\StackMiddleware\AjaxPageState->handle(Object, 1, 1) (Line: 51)
Drupal\Core\StackMiddleware\StackedHttpKernel->handle(Object, 1, 1) (Line: 704)
Drupal\Core\DrupalKernel->handle(Object) (Line: 19)
Clumps of debris from a disrupted planetesimal are irregularly spaced on a long and eccentric orbit around the white dwarf. Individual clouds of rubble intermittently pass in front of the white dwarf, blocking some of its light. Because of the various sizes of the fragments in these clumps, the brightness of the white dwarf flickers in a chaotic way.
Dr Mark Garlick/The University of Warwick
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