Удрі здобув докторський ступінь в Університеті Женеви в 1992 році та провів два роки в Університеті Рутгерса в Нью-Джерсі. Пізніше Удрі повернувся до Женеви та працював із Мішелем Майором, першовідкривачем 51 Pegasi b, першої позасонячної планети, яка обертається навколо нормальної зірки. У 2007 році Удрі був призначений повним професором факультету природничих наук Женевського університету.
↑Dennis Overbye (25 квітня 2007). 20 light years away, the most Earthlike planet yet. The New York Times. Процитовано 22 грудня 2010. The most enticing property yet found outside our solar system is about 20 light years away in the constellation Libra, according to a team of European astronomers. The astronomers said Tuesday that they had discovered a planet five times as massive as the Earth orbiting a dim red star known as Gliese 581. It is the smallest of the 200 or so planets that are known to exist outside of our solar system, the extrasolar, or exo-, planets. It orbits its home star within the so-called habitable zone where surface water, the staff of life, could exist if other conditions are right, said Stéphane Udry of the Geneva Observatory.
↑JOHN NOBLE WILFORD (19 червня 2002). Another Cousin to Jupiter Is Found. The New York Times. Процитовано 22 грудня 2010. Dr. Stéphane Udry, a member of the team from the Geneva Observatory in Switzerland, said in an interview that what was missing in this planetary system — mammoth planets extremely close to the host stars — made it a more promising solar system analog than the one announced last week by the leading team of American planet hunters. The star the Americans found is accompanied by one and probably two Jupiter-size planets at closer distances than Mercury is from the Sun.
↑Jeremy Manier (25 квітня 2007). Just like home, yet light years from Earth. Chicago Tribune. Процитовано 22 грудня 2010. As with nearly all such planetary discoveries, astronomers could not observe Gliese 581 directly because it is invisible in the glare of its sun. Instead, the European group led by Stephane Udry and Michael Mayor calculated the planet's presence from its tiny gravitational tug on the star.