NEW DELHI — India is preparing to launch at least five satellites by the end of this year, a senior space scientist says.

The Indian Space Research Organization (ISRO) plans to launch two foreign spacecraft — Spot-6, a 800-kg (1,800-lb.) remote-sensing French satellite, and the 15-kg Japanese Protiers — onboard the PSLV-C21 (Polar Satellite Launch Vehicle) in September, says P.S. Veeraraghavan, director at the Vikram Sarabhai Space Center (VSSC), a division of ISRO.

Spot-6, an advanced remote-sensing satellite built by Astrium SAS, will be the heaviest that ISRO has lofted since it put the 350-kg Italian satellite Agile into orbit in 2007. PSLV-C21 also will mark India’s 100th space mission, after 62 satellites and 37 launch vehicles since 1975.

The two foreign satellites will be launched from the spaceport of Sriharikota in the southern Indian state of Andhra Pradesh.

“The Japanese satellite has already arrived in Sriharikota and the Spot-6 is expected soon,” Veeraraghavan says.

The third spacecraft — the 3,400-kg GSAT-10 communication satellite — also is expected to be lofted in September by a European Ariane 5 from Kourou, French Guiana, the VSSC official says.

GSAT-10, worth an estimated 7.5 billion rupees ($140 million), will cater to the growing need for communication services. It is expected to have a minimum operational life of 15 years.

ISRO also is aiming to launch the Saral satellite, an Indo-French program, using the PSLV-C20 rocket during October/November, Veeraraghavan says. Saral will provide useful information for marine meteorology and sea-state forecasting, operational oceanography, seasonal forecasting and climate monitoring, as well as ocean, Earth system and climate research.