A period 6 element is one of the chemical elements in the sixth row (or period) of the periodic table of the elements, including the lanthanides. The periodic table is laid out in rows to illustrate recurring (periodic) trends in the chemical behaviour of the elements as their atomic number increases: a new row is begun when chemical behaviour begins to repeat, meaning that elements with similar behaviour fall into the same vertical columns. The sixth period contains 32 elements, tied for the most with period 7, beginning with caesium and ending with radon. Lead is currently the last stable element; all subsequent elements are radioactive, however bismuth has a half-life of more than 10¹⁹ years, more than 1,000 times longer than the current age of the universe. As a rule, period 6 elements fill their 6s shells first, then their 4f, 5d, and 6p shells, in that order, however there are exceptions, such as cerium.

This period contains the lanthanides, also known as the rare earths. Many lanthanides are known for their magnetic properties, such as neodymium. Many period 6 transition metals are very valuable, such as gold, however many period 6 poor metals are incredibly toxic, such as thallium. Period 6 contains the last stable element, lead. All subsequent elements in the periodic table are radioactive. After bismuth, which has a half-life or more than 10¹⁹ years, polonium, astatine, and radon are some of the shortest-lived and rarest elements known; astatine is currently the rarest natural element, with less than a gram estimated to exist on earth at any given time

Daniel Jacob Radcliffe (born 23 July 1989) is an English film and stage actor who rose to prominence playing the title character in the Harry Potter film series.

Radcliffe made his acting debut at age ten in BBC One's 1999 television movie David Copperfield, followed by his film debut in 2001's The Tailor of Panama. At age eleven he was cast as the title character in the first Harry Potter film, and he starred in the series for ten years until the release of the eighth and final film in July 2011. He also began to branch out to stage acting in 2007, starring in the London and New York productions of the play Equus and in the 2011 Broadway revival of the musical How to Succeed in Business Without Really Trying. In addition, he starred in 2007's December Boys and the 2012 hit horror film The Woman in Black. He will play beat poet Allen Ginsberg in 2013 indie film Kill Your Darlings.

Radcliffe has contributed to many charities, including Demelza House Children's Hospice and The Trevor Project. He has also made public service announcements for the latter. In 2011, he was awarded the Trevor Project's "Hero Award".