The first Astronomer Royal was John Flamsteed. The self-taught and highly accomplished Flamsteed earned £100 a year after Charles II issued a warrant to the Office of the Ordnance in March of 1675.
In June 1675, an additional warrant allowed for a small observatory at Greenwich. Sir Christopher Wren, a keen astronomer in his right, was appointed to build an observatory. We know it today as The Royal Greenwich Observatory.
In 1710, Queen Anne issued a warrant naming the President of the Royal Society along with other Fellows to serve as Visitors to the Observatory to try and halt its decline. Flamsteed had a bit of a problem publishing his work as quickly as all had hoped.
Due to his lack of published work, George I named Edmund Halley as successor to Flamsteed in 1720. Halley would become ‘Our Astronomical Observator in Our Observatory at Greenwich.’ Halley would later become famous for his prediction of his namesake comet.
In 1727, Queen Caroline became the first Royal to visit the observatory. Halley would then receive a supplement to his meager earnings as he received half-pay of a Post Captain.
During Nevil Maskelyne’s term (1765-1811), it was discovered that The Royal Society warrant lapsed when Queen Anne died. Thus, the Society was without authority for 50 years. Since then, a new warrant is issued by each new Sovereign.
As many appointments have a set structure, the Astronomer Royal has never really formulated a set routine for appointments. The Queen or King makes the appointment with advice from the Prime Minister, who in turn has an official recommendation from the Board of Ordnance of Admiralty.
No duties are attached to the office. The Astronomer Royal though is expected to be available for consult on scientific issues for as long as the holder remains a professional astronomer in the UK.
Since 1995, Martin Rees, Baron Rees of Ludlow is the current Astronomer Royal. Lord Rees of Ludlow was also President of the Royal Society between 2005 and 2010.