Question refer to text below:

Small, cold, and absurdly far away, Pluto has always been selfi sh with its secrets.

THE X – FILES

It wouldn't be the fi rst time Pluto has confounded expectations. In 2006, the year New Horizons was launched, Pluto vanished from the list of planets and reappeared as a “dwarf planet.” That, of course, had more to do with astronomers on Earth than any celestial sleight of hand, but the truth is, Pluto has been a tough world to crack since before it was discovered.

By the turn of the century, the hunt for that missing planet had gathered momentum: Whoever found it would earn the shiny distinction of discovering the first new planet in more than 50 years. Calling the rogue world “Planet X,”, Boston aristocrat Percival Lowell – perhaps best known for claiming to have spotted irrigation canals on the surface of Mars – vigorously took up the search. Lowell had built his own observatory in Flagstaff, Arizona, and in 1905 it became the epicenter of the search for Planet X, with Lowell calculating and recalculating its probable position and borrowing equipment for the hunt.

But Lowell died in 1916, without knowing that Planet X really existed.

Fast-forward to 1930. Late one February afternoon, 24-year-old Clyde Tombaugh was parked in his spot at Lowell Observatory. A transplant from the farm fields of Kansas, Tombaugh had been assigned the task of searching for Lowell`s elusive planet. He had no formal training in astronomy but had developed a skill for building telescopes, sometimes from old car parts and other improbable items.

(Source: National Geographic Magazine – July 2015 - http:// ngm.nationalgeographic.com/ print/2015/07/ pluto/drake-text (adapted))

In the first paragraph, the expression “sleight of hand” means