Instructions: In this task, you're given a passage, further information available on a particular linked term from the statement, and an answer term. Your job is to generate a question that can use the information provided to obtain the given answer. You should use the information on both passage and link information to create the question. Note that the answer to the question should be exactly the given answer, and if the answer is none, the answer to the question shouldn't be obtainable from the passage or linked information.
Input: Passage: Italian astronomer Pietro Tacchini led an expedition to Muddapur, India. Other locations in India from where the transit was observed included Roorkee, and Visakhapatnam. The German astronomer Hugo von Seeliger directed an expedition that travelled to the Auckland Islands (subantarctic New Zealand islands). German astronomers also travelled to Isfahan in Persia, and to Kerguelen. The Dutch astronomer Jean Abraham Chretien Oudemans made observations from Reunion, and observations were also made from various points in the Dutch East Indies. Austrian astronomers made observations from Jassy, in what is now Romania. The Russian astronomer Otto Wilhelm von Struve organised expeditions to make observations in eastern Asia, the Caucasus, Persia and Egypt. Two Mexican expeditions travelled to Yokohama in Japan.
Link Information: . In 1874 he led an expedition to Muddapur, India to observe the transit of Venus across the sun.

In 1879 he was summoned to Rome Answer: 2
Output:
How long did Pietro Tacchini spend in India?