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ISRO’s Chandrayaan-1 – detected in lunar orbit

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Using an innovative radar technique, NASA has been able to detect two spacecraft in lunar orbit from the surface of the Earth. NASA’s Lunar Reconnaissance Orbiter was launched in 2009 and was in lunar orbit at the same time as Chandrayaan-1. Although a joint experiment was designed for both spacecraft, it did not work out. LRO is still operating in Lunar Orbit today. Communication with India’s Chandrayaan-1 was lost in August 2009.  At the time ISRO engineers estimated that Chandrayaan-1’s orbit would decay and it would impact on the surface of the Moon by around 2012.  The new microwave radar technique using three of the world’s largest radio telescopes (Goldstone, Arecibo and Green Bank) first located the Chandrayaan-1 in July 2016. Remarkably it was still pretty much in its 200km polar orbit going round the Moon every 2 hours.

Chandrayaan-1 was originally (November 2008) in a 100km orbit which was raised to 200 km (May 2009)  to overcome internal heating problems. Although not welcomed at the time because the resolution of the data captured by several of the onboard instruments was reduced given the higher altitude. This raised orbit is probably the reason it survives in lunar orbit today.

One of the better write-ups, from 2009 about the demise of the Chandrayaan-1 mission from an accomplished Indian journalist T.S. Subramanian here.

Book Review: ISRO’s Earth Observation Cameras

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India’s Journey Towards Excellence In Building Earth Observation Cameras
India’s Journey Towards Excellence In Building Earth Observation Cameras

Title: India’s Journey Towards Excellence In Building Earth Observation Cameras

Publisher:  Notionpress.com

Author: Dr George Joseph

ISBN:  978-93-5206-998-9

As a late joiner to the space club, India’s space program was in “catch-up” mode for most of its early history.  Never the less, original technological innovation did take place. In this book, Dr George Joseph describes how the electro-optical sensors used on-board India’s Earth Observation satellites were designed, built and deployed. He knows because he was at the forefront leading this work during the 1970s and 1980s.

As with any account written by the those who are intimately involved, Dr Joseph brings a level intimate detail and authenticity that is not otherwise available.   His arrival at ISRO in 1973 was timely. He lead the team that built the imaging system (image intensifier and vidicon tube) for India’s first Earth Observation satellite, Bhaskara-1. In the 200 pages, the book traces ISRO’s deployments of new techniques and technology as the Indian Remote Sensing program (IRS) evolved during the 1980s. The quality and quantity of data captured increased as multispectral, stereoscopic, higher specification optics and digital technology was introduced.

ISRO’s history is littered with examples of imaginative solutions to overcome the deficit of resources.  Images of rocket nose cones transported on bikes or a bullock cart with rubber wheels for testing satellite antenna in a non-magnetic environment, have generated iconic images. They represent a lasting public perception of the ingenuity and frugality of the Indian space program. Dr Joseph describes another.  In 1973 when a dark room was not available, a kitchen in a residential apartment was converted in to one along with the solid work surface to an optical bench.

Most of the book is readable for anyone with an interest in this subject. Since,  Dr Joseph is a scientist, some technical terms such as “Modulation Transfer Function” and “scan mirror for off nadir viewing” are present. Although the book traces the evolution of imaging systems which was the author’s primary contribution during the early phase, it covers how those early techniques and technologies continue to support the 2008 Moon mission and the 2013 ISRO’s Mars Orbiter Mission.

Chapter 10 highlights another of ISRO’s contribution that many, even within India, do not appreciate – international collaboration. The US Landsat series of Earth Observation satellites was the premier supplier of Earth Observation data. During the 1980s, 1990s, and early 200s, problems with Landsat 5, 6 and 7 coincided with the time that ISRO’s EO constellation of  satellites matured. Despite the very different pedigree, ISRO EO data was sought by many nations to fill the gap left by Landsat. Chapter 10 looks at several examples of how data from ISRO’s satellites is used by Australia, Sweden, Italy USA, Brazil and Kuwait to help toward understanding and mitigating against the effects of climate change.

The book is fascinating resource not only detailing the evolution of a key asset of satellite imaging systems but the personal account of how that was achieved. An appendix with 5 sections at the end deals with some of the more technical and specialised areas such as Bhaskara TV Camera Failure Analysis, Supplementary Notes, Space based Electro-Optical Cameras of ISRO, Glossary and Memory Lane.  I found the Supplementary Notes and Memory Lane sections particularly interesting. They contain transcriptions of letters, notes and several B&W images of high quality capturing some of the key events from the time when the author was engaged with his ground breaking work.

This is an interesting read, even if you have no interest in ISRO per se. The description of space based imaging systems, by someone who built them, is sufficient justification for acquiring a copy.  How could the work be improved? This book has one of the better quality of post production that I have seen. Despite this however,  there are some minor typos that do not get in the way of comprehension but are a distraction. Something that copy editing or proofreading should have picked up. The other is my frequent complaint – absence of an index. The book is available on  paperback from Amazon but hardback only from the publisher in India www.notionpress.com. It is incomprehensible that in 2016, an ebook is not ALWAYS made available  at time of publication. A sample of the book, the forward, is available on the author’s personal website.

Book Review – From Fishing Hamlet to Red Planet: India’s Space Journey

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RedplanetTitle: From Fishing Hamlet to Red Planet: India’s Space Journey
Publisher: Harper Collins India
Author: ISRO
Chief Editor: P.V. Manoranjan Rao

This book is probably the most detailed and most comprehensive account of how the Indian Space Program was founded and has developed since 1963.   There is no single narrative that flows from the beginning to the end. Instead this is a compendium of  53 individual articles in 8 sections from 50 different contributors written at different times. This stand-alone chapter approach allows the reader to hop between sections of interest  in any order. The varying styles and the occasional repetition may distract but can also reinforce.

Many of the key individuals who played a central role in the development of the Indian Space program are no longer around, but many are and they have shared their first hand recollections in this pages. Professor UR Rao who lead the team that designed and built ISRO’s first satellite, Kiran Kumar helped develop high resolution imaging system from space, Yash Pal who was present at the start and helped realise Sarabhai’s vision of using space to drive social change and Professor Jacques Blamont who provided the payload for the first rocket launched on 21st November 1963 and sustained the Indo-French collaboration for many years.

This is probably the first book that comprehensively captures the range of ISRO achievements.  Although rockets and satellites get the limelight, the key foundations that enable those developments do not. For example section 6.1. Space and Industry Interface, emphasis the underlying infrastructure with the words “tool design and fabrication is a technology by itself”.  The same chapter details the ISRO’s extensive connections with private Indian industry that have contributed to ISRO’s success.

Although ISRO is a department of the government, several of the writers refer to the “ISRO Culture” as a differentiator that has driven its success. It is has multiple manifestations. The origins of ISRO (as INCOSPAR) and its one page constitution as drafted by Homi Bhabha provided for a streamlined decision making, putting scientists and engineers (rather than politicians and administrators) in charge; Sarabhai vision to engage  international partnership as an initial stepping stone; UR Rao initiated new purchasing processes to bypass government red-tape) to meet tight timelines when building India’s first satellite Aryabhata;  and thousands of bright, dedicated and competent ISRO employees who rolled up their sleeves and took on ambitious goals in the complete absence of infrastructure, resources and experience.

When faced with challenges of building launch vehicles, satellites and the ground infrastructure to support them, getting the job done had the priority. Record keeping for archives did not. ISRO has been particularly slow to recognise this loss for future generations. State secrecy is unnecessarily invoked to limit and prohibit publication. invoked  As happens around the world, the culture of state secrecy is used to hide incompetence or embarrassment rather than legitimate state secrets. Consequently, publications such as this become an important source of information that is not available elsewhere. Both the current and previous ISRO chairmen are to be commended in nurturing and making this book possible.

Bhabha and Sarabhai understood the importance of international collaboration and had the international connections and charisma to invoke engagement. Without the assistance of foreign nations, particularly, the USSR, USA and France India would probably not have its space program in the current form but a mere shadow of what it actually has today. All the contributions are from Indian contributors with the exception of  a special but short contribution from Jacques Blamont from France and an incidental interview transcript of an Arnold Frutkin interview as part of the NASA Oral history program from 2012. It is customary in any book review to identify some shortcomings.  Since international collaboration has been central to ISRO’s progress over the decades, there could have been more international representation. Certainly, the absence of a USSR/Russian contribution is conspicuous. This book would also have been an ideal place to capture more original images perhaps sourced from the private collections of the contributors.

One of Carl Sagan’s many quotes goes like this “In all the history of mankind, there will only one generation that will be first to explore the Solar System”. Here he highlights the chance nature of events that happen for the first time in human history and coincide with our time on earth. Abdul Kalam who played a key role in ISRO  developing India’s first rocket capable of placing a satellite in orbit (SLV-3) died in  July 2015. In January 2016  Vasant Gowariker  who among his many contributions helped develop ISRO’s solid propellent infrastructure. The publication of “From a Fishing Hamlet to the Red Planet: India’s Space Journey” is timely. It is a detailed account from the ever decreasing group of individual who were part of that journey.

Akatsuki – New arrival at Venus

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Akatsuki. Credit JAXAWith two active rovers on the surface of Mars and six satellites in orbit, the Human exploration of Mars continues as never before. Two more missions will be leaving Earth for Mars in early 2016. However, the space news of this week that has not received the due global attention is the arrival of the Japanese spacecraft, Akatsuki in Venusian orbit on Monday. Compared to the social media storm of when the Indian Mars Orbiter Mission arrived in Mars in October 2014, Akatsuki’s arrival at Venus has been an unfairly subdued affair.

The highly successful European Venus Express mission came to an end early this year, today Akatsuki is the only active spacecraft in orbit around Venus. At 400 by 440,000km Akatsuki will orbit Venus every two weeks in a highly elliptical orbit. Jaxa engineers plan to tweak the orbit and commission all 6 instruments – 3 of which are already operational.

The story of Akatsuki’s mission to Venus almost mirrored the problematic Nozomi spacecraft to Mars in 1999. Jaxa’s Nozomi spacecraft suffered engine problems and failed to orbit Mars but did fly past it in 2003. Akatsuki, launched in 2010 also suffered engine problems and achieved orbit of Venus only on its second attempt 5 years after launch. Jaxa’s engineers employed some remarkable engineering solutions to achieve this success. Akatsuki will now orbit Venus for a two-year science mission. A more detailed write-up is available at Spaceflight 1010.