New Delhi, Dec. 18 -- India's top space startups-Digantara, Skyroot and Agnikul Cosmos-have received a thumbs-up from investors as they look to scale up revenue over the next 18-24 months, marking a crucial milestone five years after New Delhi opened up space for private participation.

On Tuesday, Bengaluru-based satellite surveillance and services startup Digantara raised $50 million in its series-B funding round. The company will use the newly-raised funds to build its own manufacturing lines for satellites and optical communications technologies, and double its research and development team through 2026.

Anirudh Sharma, chief executive of Digantara, told Mint that at the heart of its new fund-raise and expansion plans is the prospect...