The National Stock Exchange (NSE), which owes its success to Very Small Apperture Terminals (V-Sats) hooked to ISRO satellites, has already warned the investors and dealers about the possibility of disturbances. NSE has cautioned its members all over the country about the effects of the meteorides on the trading activity next week. NSE has installed 1,761 V-Sats in 201 cities across the country.

Any disruption on the NSE will affect the trading on the Bombay Stock Exchange as all the chances of arbitrage as well as long or short positions would be eliminated following shutdown of either exchange. Moreover, BSE's BOLT (BSE On-Line Trading) terminals wouldalso get affected with outstation brokers failing to get access to the BSE network, say exchange officials.

However, BSE will not be affected in a big way as the exchange conducts online trading in Mumbai. However, its outstation members, who are linked through the satellite, will be affected.

Worried over these factors, market participants resorted to selling in the scrips where they had long positions. While BSE sensitive index fell 28 points, NSE's Nifty Index declined by 0.15 points to close at 868.85.

The NSE in a broadcast message for its members informed that "Comet SSP/ Tempel-Tuttle" is expected to hit the earth atmosphere over India during November 14-20, and alerted members about the possible threat to the exchange satellite to avoid any panic in the market.

NSE said in view of the above the ISRO/NOCC (network operations control center), DoT may switch off certain satellite services at a short notice or even without notice during any part of the day including the trading hours fromNovember 13 to 20.

Hence, the exchange said that it may not be in a position to inform its members well in advance about the disruption in services. ``Members may please make note of this and exercise adequate precaution in their dealing on the exchange,'' NSE said.