transits of venus and modern astronomy in india

Rajesh Kochhar

President IAU Commission 41: History of Astronomy

Indian Institute of Science Education and Research Mohali 140306, Punjab

rkochhar2000@yahoo.com

Transits of Venus and modern astronomy in India

There is an interesting historical

correlation between astronomical activity

on the one hand and the material status or

aspirations of its practitioners on the

other.

During the past three millennia, in the vast

traditionally interacting geographical area,

the centre of astronomical activity has

resided in the most prosperous,

dominant and ambitious region: Ancient

Iraq, (post-Alexandrian) Hellenistic world,

India, Muslim Culture Zone, Europe, and

USA. (Two major exceptions may be

noted. For some

reason Roman Empire showed no interest

in astronomy. Similarly astronomy failed

to enthuse the Mughal Empire in its peak

period.) It would seem that once a culture

has

established its ascendancy in its terrestrial

surroundings, it considers it its bounden

duty to unravel the mysteries of the

cosmos on behalf of the whole humankind.

The converse is also true.

To compensate for the inherent pettiness of

geo-political rivalries, a cosmic dimension

is added to it. There has been a practical

reason also. There is certain amount of

nobleness

associated with an astronomical pursuit.

This means that more nefarious goals can

be hidden behind it. Thus the 1735 French

expedition to South America was

ostensibly sent for the

measurement of an arc of the meridian at

Quito in Ecuador, but it had secret

instructions to gather intelligence on what

came to be designated the cinchona tree

( Lee 2002 p 191).

Similarly, thirty years later, James Cook’s

expedition to the South Seas for observing

the 1769 Transit of Venus provided Britain

with a pretext to reach New Zealand and

Australia.

It is no more than a coincidence that the

first English ship reached India the same

year (1608) the telescope was invented in

the Netherlands. This numerology

brings home the point that modern science

and technology have grown hand in hand

with colonial expansion, maritime trade,

and domination over

nature and fellow human beings.

Astronomy very soon developed into a

valuable navigational and geographical

aid. The first Astronomer Royal, John

Flamsteed (1646-1719),

supplemented his income by giving tuition

to East India Company cadets. It paid to

join the Company; and it paid to know

astronomy. The 1761 and 1769 transits of

Venus added a strong cultural

dimension to astronomy, made the

Governments aware and supportive of it

and gave a fillip to large-scale manufacture

of instruments.

The 18th century transits occurred at a

time when France and Britain were

engaged in bitter rivalry for the control of

waters and distant lands. The observation

of the transits

became part of this rivalry. For the 1761

event, the Royal Society sent two

astronomers to Bencoolen (now Indonesia)

and asked the British East India Company

to ‘accommodate

and maintain them’. Instructions for the

next event were more forthright. On 22

January 1768, the secretary of the Royal

Society wrote: ‘The honor of this Nation

seems

particularly concerned in not yielding the

palm to their Neighbours, and the Royal

Society intends to exert all its strength and

influence in order to have this observation

[1769 transit] made…’ As it turned out

both the French and the English palms

were left high and dry because of the

cloudy skies over both Madras and

Pondicherry. Astronomical

expeditions and instruments were seen as

symbols of a superior, science-driven

culture. Instruments were presented as

official gifts to native rulers as show-off

even when the latter had no use for them.

A telescope that had earlier been presented

to the Nawab of Arcot was borrowed back

for actual use in 1769.(The Nawab was the

leag owner of land on which Madras

stood.)

The story of the French astronomer

Guillaume Joseph Hyacinthe Jean-Baptiste

le Gentil (1725-1792) is well known. He

has the rather tragic distinction of holding

the record

for the longest scientific expedition in the

recorded world history, and that too an

unproductive one.. He set sail for South

India with a view to observing the 6 June

1761

transit of Venus; and stayed back for

1769. He reached back home after 11

years, and that too without accomplishing

his mission. Because of the Anglo-French

war, he could not arrive in India in time,

and

could observe the event only from a

moving ship, which observation obviously

had no scientific value. He decided to stay

put in the East for eight years to be able to

see the 3 June 1769 transit from

Pondicherry , but was clouded out  (Hogg

1951, p. 129). His time however was not

entirely wasted.

Gentil arrived in Pondicherry in March

1768 and stayed here for two years, before

and after the transit. He took tuition from

Tamil astronomers and learnt the

traditional Indian method of calculating

eclipses (Hogg 1951, p. 129).

When Greenwich Observatory was

established, it had no instruments. British

India now had instruments, but no

Observatory. However, what led to the

institutionalization

of modern astronomy in India was not the

love of the stars but the fear of death. The

Bay of Bengal is visited by monsoons

twice a year. The east coast of India,

the Coromandel, is rocky and full of

shoals. On top of it, Madras, unlike

Bombay, is not a natural harbour. A survey

of the coast was thus literally a matter of

life and death.

It is to facilitate coastal survey that an

astronomical Observatory was established

in Madras, in 1787. It was a private

Observatory to begin with but was taken

over by the Government in 1790.

One of the instruments was a clock by

John Shelton, which had been made for the

Transit. It is identical with the clock used

by Captain James Cook, and in the

determination of Mason-Dixon line in

USA.

It is not clear when the East India

Company bought the clock and sent to

India. It is now at Kodaikanal and still

accurate enough to be used as an ordinary

timekeeper.

In 1844, after ten years of sustained work,

Thomas Glanville Taylor at Madras

Observatory brought out the famous

Madras Catalogue of more than 10,000

stars, which won high appreciation.

It was however the only worthwhile

contribution from Madras, which lost its

charm for the British after the

establishment of Observatories in South

Africa and Australia.

Madras Observatory had been established

as an aid to Trigonometrical Survey of

India. Once the Survey became self-

sufficient, the Government lost interest in

the Madras Observatory.

The attitude towards pure astronomy is

best brought out by a little -known

incident. In 1834, on orders from the

Government, instruments were issued to

John Cumin for

the observation of the opposition of Mars.

The Surveyor General, George Everest,

made a strong protest against the loan,

sayings: ‘The discoveries which the late

astronomer

of Bombay is likely to make in science

would hardly repay the inconvenience

occasioned by retarding the operations of

the Great Trigonometrical Survey...’

Curnin had been the first Director of the

Colaba Observatory and was dismissed

from service in 1828. His stock would not

have been very high in British India.

And yet, the incident does sum up the

lowly position which pure astronomy

occupied in relation to geodesy and

geography.

By the time the 1874 transit of Venus

came, positional astronomy had made way

for physical astronomy. Spectroscopic and

photographic techniques were used in the

Indian observations of the solar eclipses of

1868, 1871 and 1872, which attracted

observers from Europe also. The French

astrophysicist Pierre Jules Cesar Janssen

independent co-discoverer Joseph Norman

Lockyer (1836-1920). During his post-

eclipse stay at Simla, Janssen created the

first spectrohelioscope, which facilitated

daily examination of the sun.

independent co-discoverer Joseph Norman

Lockyer (1836- 1920). During his post-

eclipse stay at Simla, Janssen created the

first spectrohelioscope, which facilitated

daily examination of the sun.

The scientists’ agenda for the 1874 transit

ran deeper. What was advertised was the

momentary passage of Venus in front of

the solar disc; what was planned was a

long-term

study of the disc itself. British (and

European) solar physicists wanted

photograph of the sun for each day of the

year. Since this was impossible in

Europe’s weather conditions,

data was needed from the colonies. The

British Association for the Advancement

of Science even passed a resolution asking

the Government of India to make

arrangements

for observing the event and to provide

instruments which were afterwards to be

transferred to a solar observatory. Such

was the prestige enjoyed by science and

scientists

in Europe at the time that the British

Empire as the owner of most of the

world’s sunshine could not but respond

favourably even if partially.

The 1874 transit eventually led to regular

solar physics studies in India, even though

the exercise took 25 years. The stepwise

development was as follows.

Telescopes were purchased expressly

for the observation of the 1874 event

Facilities of a more permanent nature

were then created using these and

other telescopes. Solar photography

was taken up at Dehra Dun (1878-

1925) and solar spectroscopy Poona

(1888-1912). Data was sent to Britain.

A Solar Physics Observatory was

established at Kodaikanal in 1899

which now has solar picture data with

the same instrument for the longest

uninterrupted period.

The 1874 transit of Venus

As part of a bigger programme, and

under the guidance of the Astronomer

Royal, Sir George Airy, the transit

observations were planned at Roorkee

( now Uttarakhand) and Lahore, under

the supervision of Col. James Francis

Tennant. Note that it was Tennant and

not Airy's bete noire, Norman Robert

Pogson, the Madras Astronomer, who

was asked to do this work.

More than 100 photos of the sun were

taken at Roorkee and sent to Airy.

Photos from all over were reduced by

Captain G. L. Tupman who wrote:

‘There is only one really sharp

image in the whole collection, including

the Indian and Australian contingents,

and that is one of Captain

Waterhouse’s wet plates taken at

Roorkee’.

Dehra Dun Observatory (1878-1925)

Next, Lockyer used his equation with Lord

Salisbury, the Secretary of State for

India, for making arrangement for

solar photography in India.

Salisbury wrote to the Viceroy on 28

September 1877: ‘Having considered

the suggestions made by Mr. Lockyer,

and viewing that a study of the

conditions of the

sun’s disc in relation to terrestrial

phenomenon has become an important

part of physical investigation, I have

thought it desirable to assent to the

employment for a

limited period of a person qualified to

obtain photographs of the sun’s disc by

the aid of the instrument now in India [

for the transit]’. Accordingly, starting

from early 1878 solar

photographs were regularly taken at Dehra

Dun under the auspices of Survey of

India, and sent to England every week.

Dehra Dun continued solar

photography till 1925, but

more out of a sense of duty than

enthusiasm. The larger of the two

photoheliographs fell into disuse, and

in 1898 Lockyer was stung by on-the-

spot discovery that ‘the dome has been

taken possession of by bees’.

St Xavier’s College Observatory, Calcutta

(1879)

sunny India caught the attention of

astronomers in the continent also. The

Italian transit-of-Venus team led by

Professor P. Tacchini

of Palermo Observatory stationed itself in

Bengal, its Chief instrument being the

spectroscope, `an instrument not

recognized in the equipment of any of

the English parties’.

A co-opted member of the Italian team was

the Belgian Jesuit Father Eugene Lafont

(1837-1908) professor of science at St.

Xavier’s College, who though no

researcher himself was an inspiring educator

and science communicator. Tacchini

suggested to Lafont ‘the advisability of

erecting a Solar Observatory in Calcutta,

in

order to supplement the Observations made

in Europe, by filling up the gaps caused

in the series of solar records by bad

weather’. St Xavier’s was an elitist

College providing

education to sons of Europeans, Anglo-

Indians, rajas, zamindars, and Indian

men of note. Lafont therefore `secured

great influence among these classes’

which he now put to good use in the

service of science.

Lafont soon collected a sum of Rs 21000

through donations, including Rs 7000

from the Lieutenant Governor of Bengal.

A 9” refractor by Steinhill of Munich

was

purchased and housed in a spacious dome

constructed for the purpose.

Unfortunately, no research or teaching

use was ever made of

this facility. This is unfortunate, because

observational astronomy has remained

outside the education system.

Takhtasinghji's Observatory Poona (1888-

1912)

Set up by the Bombay Government, it was

India’s first modern astrophysical

observatory. Unfortunately, it was a

personalized facility. The original plan was

to establish a spectroscopic laboratory at

Elphinstone College Bombay for use by

the students. The initiator of the proposal

was a

lecturer in the College, Kavasji Dadabhai

Naegamvala (1857-1938), who obtained

seed money of Rs 5000 from the

Maharaja of Bhavnagar and a matching

grant from the Bombay Government.

While in England in 1884 for buying the

equipment, he was persuaded by the

Astronomer Royal and Lockyer to build

a spectroscopic observatory instead.

Since Poona was a better astronomical site

than Bombay, in 1885 Naegamvala was

transferred there to College of Science

where the Observatory came up in 1888.

Since Poona was a better astronomical site

than Bombay, in 1885 Naegamvala was

transferred there to College of Science

where the Observatory came up in 1888.

Its chief instrument was a 16½ inch aperture

silver-on-parabolic glass Newtonian

made by Grubb. In addition, Lockyer

equipped Poona as a satellite facility.

A six-inch Cooke equatorial purchased by

the Government for the 1874 transit

observation from India had been loaned

to Lockyer’s Observatory in South

Kensington.

The India office also purchased two

spectroscopes from Hilger (one solar, the

other stellar) for his use. The equatorial

and the spectroscopes were given to

Naegamvala so that he could observe

with them and send raw data to Lockyer

From December 1903 to November 1904 in

Poona, observations were made on as

many as 327 days. Out of these, 31 days

were unfavourable for any observations,

and on six

days no spots were recorded. Spectroscopic

observations were made on 216 days,

and 422 sunspots examined. Dehra Dun

sent a total of 488 8-inch negatives

during 23 October 1903 to 6 November

1904. Similarly data was received from

Kodaikanal and Maurtius.

Expectedly, relationship between Poona and

South Kensington was uneven.

Whenever South Kensington found fault

with data collection at Poona, it did not

write directly,

but formally complained to Naegamvala’s

British superiors. Yet, when Kodaikanal

Observatory was being planned, Lockyer

suggested Naegamvala’s name for the

directorship.

but formally complained to Naegamvala’s

British superiors. Yet, when Kodaikanal

Observatory was being planned, Lockyer

suggested Naegamvala’s name for the

directorship.

The position was however offered to an

Englishman, Charles Michie Smith, a

non-descript physics professor at

Madras. Lockyer and Astronomer Royal

constituted two independent centres of power

in England, and Kodaikanal came under

the latter’s sphere of influence.

Naegamvala took observations till the very

last date of his employment, 11 January

1912, ‘when in accordance with the

official notification,

the existence of the Observatory was

terminated’, and all equipment was sent

to Kodaikanal.

Thus instead of creating a permanent

educational facility, a temporary research

facility was created for the primary

benefit of European solar physicists.

Kodaikanal Observatory (1899)

If the 1874 transit of Venus was important

for solar physicists, so was the severe

famine of 1876-77 in the Madras

Presidency. Monsoons fail at times, but

the severity of famines was

particularly high in the colnial period

because of large-scale export of food

grains from India to Britain in utter

disregard of local requirements. This of

course is a later

assessment. In 1879, Lockyer presented a

report to the Indian Famine Commission

claiming that famines were correlated

with sunspot minima.

There is no doubt that Lockyer and many

others genuinely believed in a correlation

with solar activity and terrestrial

weather.

But is also a fact that the practical benefits to

be derived from a study of the sun were

exaggerated to gain Government support.

In 1881, Government of India’s chief

meteorologist Henry Francis Blanford

reported to the Famine commission that

no such simple correlation as suggested

by Lockyer existed.

In any case, the Government decided to go

ahead with the Solar Observatory. It was

decided to wait till the neurotic Madras

Astronomer Pogson was dead. This

happened in 1890.

Steps to set up Solar Physics Observatory

were initiated in 1893, culminating in the

Kodaikanal facult which formally came

into existence on 1 April 1899.

Kodaikanal started shakily, but rose to great

heights under George Evershed who

arrived in 1907 no doubt to be able to

work in solitary splendour.

His 1909 discovery of the Evershed Effect

of radial flow in sunspots remains the

most outstanding work ever done in the

Observatory.

Concluding remarks

In the 18th century, when Britain and France

were fighting for control of maritime

trade and distant lands, astronomy

became a symbol of one-up-manship

( cf. space race between USA and

USSR in the cold war era).

By the time of the 19th century transits of

Venus, Britain had become the

uncontested world power. Science had

sufficiently progressed in the West to

give the scientists a high social and

political profile.

Supporting pure science was a proof of the

good sense of a Government. ( In the

18th century, support for geodesy,

geography and natural history by

the Dutch and English East India Companies

pleased the scientific community and

diverted attention away from the

Company’s unsavoury activities.)

A large number of telescopes were made for

purchase by the British Government for

field expeditions. These later became the

nucleus for observatories.

It was fortunate that before and after the

1874/1882 transits a number of solar

eclipses took place in quick succession.

There was thus created a climate

supportive of pure astronomy.

Indian experience provides a number of

valuable lessons which are relevant

even today for all.

The most outstanding contributions

from Madras and Kodaikanla

Observatories were the Madras

catalogue of southern stars (1844) and

Evershed Effect (1909). These were

also the only times when India had

state-of -art instruments.

•Up to the first half of the 20th century,

the technological base of pure science

was quite modest. India could maintain

the equipment it had and improvise

also. But with passage of time science

has become

more and more a child of high technology to

the extent that in industrially-

challenged countries, (imported)

equipment tends to overwhelm the user

rather than be a tool in their hand.