On March14, one of science's brightest starswent dark. Stephen Hawking, theworld-famous British scientist, died at 76 in Cambridge, UK.

    Hawking isconsidered to be the greatest scientist in history since Albert Einstein. Hecame up with the theory that the universe (宇宙) began with the Big Bang (大爆炸) and will endin black holes. He also wrote books to help common people understand the universe.His most famous book is A Brief History of Time, which has sold more than 10million copies around the world.

    Besideshis scientific achievements, Hawking was also someone who had a strong will (意志) and optimistic (乐观的) attitude.

When Hawking was 21, he got a serious illness thatstopped him from walking and talking. Later in life, he had to sit in awheelchair and "speak" by using a computerized voice. But this didn'tstop him from living a meaningful and colourful life. "If one is physically(身体上) disabled, one cannot afford tobe psychologically (心理上) disabled as well," heonce said.

    Hawkingtravelled the globe to attend science conferences, visiting every continent. Hewas also a fan of pop culture and appeared on TV shows.

    He celebratedhis 60th birthday by going up in a hot-air balloon. When he was65, he took partin a zero-gravity (零重力)flight to experience weightlessness. He hoped to travel into space one day.

    In 2013,Hawking spoke about how he felt life was unfair when he got ill at first."But now, 50 years later, I can be quite satisfied with my life," hesaid.