Explanation

• The Hubble Space Telescope is a joint project of NASA (USA) and ESA (European Space Agency).
• It was launched in 1990 into low Earth orbit.
• Scientists like John C. Mather contributed to its development and research.
• It is used for observing distant galaxies and space objects.

Last verified on 08-06-2026

Explanation

• Discoverer: Alexander Fleming
• Year of discovery: 1928
• Place: St. Mary's Hospital, London
• First patient treated with penicillin: Albert Alexander
• Date of first treatment: 12 February 1941

Last verified on 14-09-2026

Explanation

• Nicolaus Copernicus proposed the heliocentric model.
• Heliocentric means the Sun is at the center.
• Earth and other planets revolve around the Sun.
• Proposed in the 16th century.
• Ptolemy supported the geocentric model (Earth-centered).

Explanation

• A Barometer is an instrument used to measure air (atmospheric) pressure.
• It helps in weather forecasting by measuring changes in atmospheric pressure.
• The mercury barometer is the oldest type of barometer.
• It was invented by Evangelista Torricelli in 1643.
• Barometers are widely used in meteorology and aviation.

Last verified on 09-07-2026

Explanation

• Heinrich Wilhelm Waldeyer coined the word "neuron" in 1891.
• He based it on the ancient Greek word for sinew or cord.
  
• Neuron theory/doctrine emerged at the end of the 19th century.
• Core claim — Nerve tissue = individual cells; each is a genetic, anatomic, functional, and trophic unit.
  
  Last updated by NA on 09-09-2026