I. What is the Ptolemaic Geocentric Model? The Ptolemaic Geocentric Model, also known as the Ptolemaic system, is a cosmological model that places the Earth at the center of the universe. This model was developed by the ancient Greek astronomer Claudius Ptolemy in the 2nd century AD. According to this model, the Earth is stationary … Read more
I. What is the Gas-generator Cycle? The Gas-generator Cycle is a type of rocket engine cycle used in propulsion systems. It is a method of powering a rocket engine by burning a fuel and oxidizer mixture to produce high-pressure gas, which is then used to generate thrust. This cycle is commonly used in liquid-propellant rocket … Read more
I. What are WIMPs (Weakly Interacting Massive Particles)? Weakly Interacting Massive Particles, or WIMPs, are hypothetical particles that are considered one of the leading candidates for dark matter. Dark matter is a mysterious substance that makes up about 27% of the universe, yet it does not emit, absorb, or reflect light, making it invisible and … Read more
I. What is the South African Astronomical Observatory (SAAO)? The South African Astronomical Observatory (SAAO) is a premier astronomical research institution located in Cape Town, South Africa. It was established in 1820 and is the oldest scientific institution in the country. The SAAO is operated by the National Research Foundation of South Africa and is … Read more
I. What are Astrochemical Isomers? Astrochemical isomers are molecules that have the same chemical formula but differ in the arrangement of atoms. These molecules are crucial in understanding the chemical processes that occur in space, particularly in interstellar clouds where stars and planets are formed. Isomers can exist in different forms, such as structural isomers, … Read more
What is a Lunar Eclipse? A lunar eclipse occurs when the Earth passes between the Sun and the Moon, casting a shadow on the Moon. This phenomenon can only happen during a full moon when the Sun, Earth, and Moon are aligned in a straight line. The Earth’s shadow has two parts: the penumbra, which … Read more
I. What is Full Flow Staged Combustion? Full Flow Staged Combustion (FFSC) is a type of rocket propulsion system that is known for its high efficiency and performance. It is a complex and advanced technology that involves the use of multiple combustion stages to maximize the energy output of the rocket engine. FFSC is often … Read more
Learn how satellites are controlled from the ground, how onboard systems keep them stable, and what happens when operators need to correct a spacecraft in orbit.
Low Earth orbit is becoming crowded because satellites, launches, and debris are multiplying faster than orbit can safely absorb.
Explore what creates space junk, why it accumulates in orbit, and how satellites, rocket stages, and collisions make the problem worse.