podcast Archives - AstrotalkUK

Episode 93: Exploring the surface of Titan

By Gurbir Dated: January 14, 2021 Leave a Comment

In the early hours of Christmas day 2004, a small probe called Huygens separated from larger spacecraft Cassini. Three weeks later on 14 January it descended through Titan’s atmosphere to make the most distant soft landing in the solar system to date. Huygens transmitted data during its 136 minute descent through the thick atmosphere and a further 130m minutes from the surface until Cassini disappeared below the horizon.

Prof. John Zarnecki was the principal investigator for the UK based team that built the instruments that first made contact on the surface of Titan, Saturn and the solar system’s largest Moon.

In this conversation, recorded in December 2020, prof. Zarnecki recalls the how the mission came about, the science Huygens revealed at the time and today, a decade and a half later. Cassini-Hugens was a joint mission between NASA and ESA. He also shares his views on the value of international collaboration in space.

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A video of this interview is available on Youtube.

Episode 92: Revisiting Panspermia with Prof. Wickramasinghe

By Gurbir Dated: January 1, 2021 Leave a Comment

The idea of Panspermia, that life exists throughout the universe and spreads via asteroids, comets and cosmic dust, has been around for a long time. Two of the strongest advocates were Professor Fred Hoyle and Professor Chandra Wickramasinghe.

In this episode I spoke at length with Professor Wickramasinghe about his long and distinguished career championing the idea of panspermia the covering the topics:

Initial difficulties in establishing Panspermia as a legitimate and respectable topic for scientific study.
Professor Wickramasinghe’s journey in 1960 form Cylon (as it was known at the time) to Cambridge as Hoyle’s Phd student.
His personal recollections of Fred Hoyle (initially his Phd supervisor and later collaborator) and Arthur C Clarke, who had made Cylon his home in the late 1950s.
His views on how the research on Panspermia has developed and where it stands today

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Episode 91 – ISRO and the Spy who was not

By Gurbir Dated: November 15, 2019 Leave a Comment

One of the most fascinating and colourful characters associated with the Indian Space Programme is Narayan Nambi.

In 1994, Nambi Narayanan an ISRO aerospace engineer was falsely arrested by the Investigation Beuro on charges of espionage. He was accused of passing on confidential launch vehicle flight test data to foreign nationals. In 1996 he was cleared by the Central Investigations Bureau and India’s Supreme Court found him not guilty in 1998. In 2019 he was presented with India’s third-highest civilian award, the Padma Bhushan.

In 1966 he joined ISRO or INCOSPAR as it was known at that time. With the guidance and support of Vikram Sarabhai, he went to study liquid and cryogenic engine technology at Princeton in 1969. He worked on the early stages of the development of the Vikas liquid engine which now powers two of the four stages of the PSLV.

Some of the topics we discussed include:

During the 1960s he visited the Spadadam site near Carlisle. Today it is a Royal Airforce Station but in the 1960s it was the site used by the British Government test rocket engines and to develop Blue Streak – an Intermediate Range Ballistic Missile.
In 1974 ISRO concluded a barter arrangement – no money changed hands. India would provide 100 man-years trained engineers. 75% of this time would towards supporting France developing their (then new) Ariane 1 launcher and 25% would be used by India to develop the Vikas Engine with the technology transfer from France. Indian engineers would also build, test and qualify 100,000 pressure transducers for France.
He claims to be the architect of this unique barter arrangement. In addition to being the father and architect of the PSLV.
He suspects that the intelligence Beuro picked on him to slow down the Cryogenic engine development and remove him as project director.
Speculating on the why the Vikram lander failed to make a soft landing he thinks it may have been related to the automatic landing sequence (software) or an issue with the braking thrusters.
He is an advocate of an Asian Space Agency lead by India.
He believes China space programme is not ahead of India’s because India has succeeded with the Mars Orbiter Mission.
He would like India and China to increase collaboration in space.
In 2017, he published a book on his experiences and a film based on the book will be released in late 2019.

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Episode 89 – Carbon Nanotubes

By Gurbir Dated: October 25, 2019 1 Comment

In his 1979 novel, Fountains of Paradise, Arthur C Clarke imagines a cable stretching from the Earth’s equator to Geosynchronous orbit. He called it a “space elevator” and imagined it would be constructed from continuous pseudo-one-dimensional diamond crystals. Bangalore based NoPo Technologies is now commercially producing Carbon Nanotubes. Could this material, one day be used to construct Clarke’s space elevator?

Materials that offer high strength alongside low mass are highly sought after by the aerospace industry. In the past, it was aluminium, titanium and Carbon fibre. The new wave of materials consists of Graphene and Carbon nanotubes. Carbon nanotubes like diamonds, soot and graphene are allotropes of Carbon. Same atomic structure but differ in physical construction.

NoPo Technologies was established in 2011 by the CEO Gadhadar Reddy and is already commercially supply Carbon Nanotubes to Japan and elsewhere.

Some of the themes we discussed include:

NoPo Technologies was incorporated in 2011 and is probably the only producer of Carbon Nanotubes in India at the present.
Carbon Nanotubes have desirable attributes of high thermal and electrical conductivity, tensile strength, resilience to radiation and are extremely lightweight.
Nopo Technologies commercially produce single-walled Carbon Nanotubes of about 8 nm diameter and 2000 nm long.
Use cases currently include lightning conductors on aircraft, insulators for cryogenic fuel tanks, black surfaces for star trackers on spacecraft and molecular scale filters that can be used for producing biological membranes or even water filters for desalination plants.