Photo
courtesy PC Hariharan
A great reason to go to work in a place like Tata
Institute of Fundamental Research is that you get to meet and work with friends
like Ramesh. We entered TIFR at about the same time in 1964, I as an IIT Bombay
graduate and he as a graduate of what is now the BARC Training School. We were
both interested in science in general and had formal training in multiple
disciplines.
It is not uncommon for scientists to be very focused on their
discipline. This was not our cup of tea! Ramesh and I had broad interests in
science, and we had friends in many disciplines. Knowing Ramesh was to me like
having a pass to audit courses in physics and astronomy. Another benefit I got
from being a friend of Ramesh was getting to know several of his training
school colleagues. One of them, Dr PC Hariharan, continues to be a friend to
this day.
Ramesh and I got to meet soon after joining TIFR, more or
less on the same day in 1964. Ramesh had earned an MSc in maths at Allahabad University
and a master’s in statistics at ISI, Calcutta. Subsequently, he did the one-year
post-graduate course at the Atomic Energy Training School, focusing on physics.
He came to TIFR to do physics and had a keen interest in astronomy.
Our Work on Computers for Handling Telescope Data
This was the time a new breed of small computers, designed
for handling scientific data and for online control of instruments, was hitting
the market. Prof Govind Swarup, who headed Radio Astronomy at TIFR, was keen to
utilize this type of computer to enhance data handling at the Ooty Radio
Telescope. Ramesh and I teamed up together to make plans. There was a Varian Computer
which met our expectations that was affordable. If I remember right, it was the
Varian 620/i priced closer to 10,000$ than to 20,000$, and the US$ was worth
only 25 Rupees. But getting dollars to import scientific computers was not that
easy. If there had been a local agent, his commission could have been paid in
rupees and we would need to ask for fewer dollars, but there was no local
agent. There was no choice but for us to call up businessmen to ask if they
would become the local agent of Varian! At the request of the purchase section,
Prof MGK Menon, the Director, TIFR, made this call!
Blue Star agreed and our job of importing the computer
became easier. Labs outgrow their computers like children outgrow their jeans. Ramesh
and I teamed up again, to do the preparatory work to select a computer, and
seek Government permission to import it. A new phenomenon had to be faced now. Computer
users, including major astronomy groups in the world, were making their
software available free to each other. It did not matter if a computer was
costly or cheap; it did not matter if it was relatively fast or slow! What was needed
was the one which had the largest collection of usable astronomy software, ideally
ready to plug and play. Ramesh and I went to Delhi and tried to convince the
officials of our case for a Vax 780 computer. But they seemed to be under
strict orders to minimize spending scarce foreign exchange on importing such
things as computers! Finally, the Radio Astronomy Group did succeed in getting
its VAX 780.
When Ramesh Received Homi Bhabha as a Visitor
The Ooty Radio Telescope site was inspected by Homi
Bhabha before being finalized. Ramesh was the guide when Dr Bhabha went to
inspect the site. (Prof Govind Swarup was being treated for a medical problem
at the Breach Candy Hospital in Bombay at that time). Swarup and Ramesh had done a lot of the
searching of possible sites. The north-south slope of the ground had to be such
that the telescope site could support a cylindrical radio telescope parallel to
the ground and to the earth’s axis. It had to be large enough to house a telescope
that was over 500 meters long 30 meters wide. It did not matter if leopards
came for occasional visits!
A couple of years after work had begun on the telescope,
Usha and I had been in Ooty for our honeymoon. Ramesh and Sudha gave us lunch
at their place. We risked a leopard encounter in the interest of astronomy and
visited the telescope site! Even now, you can ask Usha the latitude of Ooty.
She will give you an answer accurate to 3 significant places!
Ramesh took keen interest in science, attended all
important talks and read a lot. He also spoke his mind. However, he developed
the feeling that the approach of using lunar occultation to get accurate
measurements of radio sources was being given too much importance in the Group.
He kept arguing for using Interplanetary scintillation as an alternative tool
to enhance the accuracy of telescope observations. He encouraged many younger
members of the team to look into this possibility. However, he did not choose
to do some of this work himself and write a thesis. The Group was deep into a
survey of the sky using the Lunar Occultation technique. One could not persuade
them to take their focus away from this.
Much later, in 2011, Ramesh looked back at his Bombay and
Ooty years.
In response to a question
about his papers, this is what Ramesh said, (covering only his work in India).
“I’ve been very poor at publishing papers. I ’ve been an
idea man who’d work in a team, get things done, would not put my name up. So, (he
lists papers that he wrote) two papers from Kalyan telescope. The paper
announcing the construction and the completion of the Ooty telescope. Paper on
pulsars, and no paper on Inter Planetary Scintillation”. He was in science
because it was exciting. He was not in any hurry to earn a PhD. He preferred to
go to the USA and do a PhD from scratch, taking courses and all.
Ramesh at the University of Maryland
I met him a few times in the USA, when I was at the Carnegie-Mellon
University, Pittsburgh, for a couple of years. Pittsburgh was not far from
College Park, MD, where he and Sudha lived. I have been in touch with him
later, meeting him several times during his Indian visits. However, the
frequency of meetings could not be compared to what it used to be at TIFR. This
was a great loss to me as the developments in astrophysics and cosmology in the
decades since 1971 have been phenomenal. If I had been in touch with Ramesh, I
would have understood more of it than I now do.
Ramesh, on the other hand, got into the thick of all
that. Some of his work continued to involve big telescopes. After earning his
PhD, he worked with the big telescopes at Green Bank, and wrote the calibration
scheme of the Very Large Array in New Mexico.
Ramesh and a great experiment in astronomy, COBE
There has been a great tradition in Physics of flying
sophisticated experiments above the bulk of the atmosphere using high altitude
balloons. Microwave radiation streaming in from all directions of the cosmos
has also been studied this way. The radiation had seemed to be quite uniform,
which could not be explained. The universe must have had seeds of the huge
structures we see now, and the seeds must be seen in the radiation. Huge
galaxies occur in big clusters and there are huge voids where there is nothing.
Some astronomers found that the huge clusters of galaxies were attracting other
galaxies gravitationally, making them move very fast. The time had come to put
sophisticated experiments on satellites, to study all this better. In
mid-Seventies, Nasa invited proposals for satellite-borne experiments. It took
years for a project proposed at that time, named the Cosmic Background Explorer
(COBE), to be launched. Ramesh contributed significantly to the design and
implementation of the systems to collect and analyze data from this satellite.
COBE achieved a lot. It confirmed that the cosmic
background radiation was black body radiation at 2.725 deg K plus/minus 0.002
deg K. This was a necessary finding to confirm the theory that the universe
arose in one big bang. The finding indicated that nearly all radiant energy of
the universe was released in the first year after the bang. COBE also showed
that the background radiation was not really uniform. It showed
non-uniformities at the level of 1 in 100,000 in conformity with expectations
from the great structures we observe of galactic clusters and voids. COBE also
carried out surveys of Cosmic Infrared Background, and detected several
galaxies which had formed very early in the evolution of the universe.
Image Credit: NASA
https://lambda.gsfc.nasa.gov/product/cobe/
COBE’s results have stood the scrutiny of comparison with
results from two later satellite missions asking similar questions and using
more sophisticated instrumentation. Not surprisingly, two Principal
Investigators of the project John C Mather and George Smoot earned Nobel Prizes,
in the year 2006. COBE had involved more than 1,000 researchers, engineers and other
participants. John Mather had coordinated the entire process and also had
primary responsibility for the experiment that revealed the blackbody form of
the microwave background radiation. George Smoot had main responsibility for
measuring the small variations in the temperature of the radiation. These were
the evidence of the seeds for the huge clusters and voids that were to come.
George Smoot calls them wrinkles in time. The clusters and voids that came out
of these seeds were big enough to shape the fabric of space time around them,
according to the theory of relativity.
Ramesh had worked in Mather’s team. It was a fitting
finale to his lifelong work in astronomy, astrophysics and cosmology.
After
the COBE project’s conclusion, Ramesh worked for some more time with NASA.
During this time, he led the support for various NOAA/NASDA sea surface
measurement efforts.
Acknowledgement: I thank Velu Sinha, Ramesh's son and PC Hariharan, Ramesh's friend, for having read through my draft and giving me their comments.
References:
1) https://lambda.gsfc.nasa.gov/product/cobe/ for
the image
2) https://www.nobelprize.org/prizes/physics/2006/summary/
