The cover of APJ Abdul Kalam's bestselling autobiography.

In one after another hall at a defence laboratory in Hyderabad, India's military missiles under development were kept under security. It was perhaps the first time they were being shown to this writer, then a news reporter for the Press Trust of India (PTI) news agency.

"This is Prithvi, this is Akash, this is Nag," explained Avul Pakir Jainulabdeen (APJ) Abdul Kalam, who was then the chief of India's Integrated Guided Missile Development Programme. When we came to the last hall he stopped to say,"This is our Brahmastra (super weapon). Don't write anything about it now." That was sometime in 1980s.

The Brahmastra was the Agni missile, India's Inter Continental Ballistic Missile. Many versions of Agni missile have now successfully flown. Kalam, the famous rocket scientist who played a prominent role in advancing India's nuclear programme and who became the first technocrat to become India's 11th President (2002-2007) died of cardiac arrest on 27 July, 2015 plunging his countrymen in grief. He was 83.

He collapsed while delivering a lecture on 'Livable Planet' at Indian Institute of Management in Shillong of which he was a visiting professor — an assignment he undertook because of his passion to teach and mingle with students and children after he ceased to be the President.

Son of a boat owner and raised in Rameswaram in the southern state of Tamil Nadu, Kalam was once a newspaper boy who dreamed of becoming a fighter pilot. But fate had something else in store for him.

After studying physics and aerospace engineering in Madras (now Chennai) he launched his scientific career in the defence and space agencies where he helped develop India's first satellite launch vehicle and guided missile programme that earned him the nick name "Missile Man". Kalam became a household name in 1998 after his pivotal role in the Pokhran nuclear tests when India detonated five nuclear devices including a hydrogen bomb.

A visionary and a dreamer, Kalam remained passionate about transforming India into a developed country by 2020 — what he called Vision 2020. He also had a vision for the entire space faring community. Announcing at the Space Summit in Bangalore in 2003 his vision "for a prosperous, happy and secure planet earth" he appealed to space faring nations "to work toward a long term global space missions to address the impending crises in energy, water and minerals and avoid terrestrial war being drawn into outer space."

He also called for an International Space Force made up of all nations to protect space assets from any terrestrial geo-political war spilling into outer space. Kalam believed "space technology is almost a green technology because it can enhance the quality of human life on the earth."

In his address to the Boston University symposium on the future of space exploration in 2009 he anticipated the need for creation of space satellite service stations as a permanent international facility for enhancing the life of all the spacecraft in geostationary earth orbit through in-orbit maintenance.

Kalam's other visionary ideas included the possibility of mining Helium-3 from Moon as a valuable fuel for thermonuclear reactors. He envisioned that Moon could become a potential transportation hub for interplanetary travel and a “telecommunications hub” for interplanetary communications also. With its weak surface gravity the Moon also has other advantages as a source of construction materials, he felt.

The visionary scientist had said that "electromagnetic mass drivers powered by solar energy could provide low-cost transportation of lunar materials to construction sites in near Earth orbit." Because there is no air or water to degrade large-area thin film devices, Moon is the ideal environment for large-area solar converters, Kalam said in one of his talks.

All this, Kalam said would lead to "the need for an International Space Force to protect world space assets in a manner which will enable peaceful exploitation of space on a global cooperative basis."

With Kalam's demise, India’s scientists will miss their champion and star supporter in New Delhi. Unlike in the United States, the role of President in India is purely ceremonial, but being non-political Kalam could cut across political parties while his image as father of India’s missile programme helped him promote science and technology. An approval from Kalam almost always resulted in budgetary support for such projects like the $250 million nanotechnology initiative, or the manned space mission.

When someone asked Kalam the secret of his almost limitless energy, he replied, "When you give selflessly you gain energy."