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Topic Review
Electromagnetic Spectrum
The electromagnetic spectrum is the range of all possible wavelengths of electromagnetic radiation, ranging from high energy gamma rays through visible light and down to low energy radio waves. Various astronomical phenomena can only be observed via specific wavelengths different from visible light. By scanning the sky in the complete spectrum of electromagnetic radiation via optical telescopes, X-ray telescopes, microwave telescopes and radio telescopes, astronomers gather information that wouldn't be accessible if they were just observing via visible light. Visible light is a small fraction of the entire electromagnetic spectrum with wavelengths ranging from 380 nm (nanometres or 10-9 m) to 740 nm.
  • 141
  • 24 Apr 2025
Topic Review
Emission Nebula
An emission nebula is a cloud of interstellar gas and dust that emits light in different colours. There are several different types of emission nebulae with diverse sources of energy that are responsible for the glowing of gas and dust. Their colour varies depending on the degree of ionisation and the chemical elements of the nebula. 
  • 33
  • 24 Apr 2025
Topic Review
Degeneracy
Degenerate matter is created under the enormous pressures of very dense neutron stars. The properties of degenerate matter are determined by quantum mechanics and are therefore completely different from the properties of the matter that surrounds us. 
  • 38
  • 24 Apr 2025
Topic Review
Molecular Clouds and Dark Nebulae
A molecular cloud is an accumulation of interstellar gas and dust. These clouds have very low temperatures of just 10 to 30 kelvin and therefore the hydrogen is primarily composed of molecular hydrogen or H2. Compared to the mainly ionized hydrogen in other areas of the interstellar medium, less than 1% of all hydrogen in the Milky Way is bound in molecular clouds. The rest is in the form of atomic hydrogen which can become a molecular cloud at a later point in time. 
  • 56
  • 24 Apr 2025
Topic Review
Exoplanets
One of the most fundamental questions any human being can ask is: are we alone in the universe? The knowledge about the existence and characteristics of exoplanets is indispensable for giving us an answer. Everything that we have learned up to now indicates that life might exist on millions and billions of other planets in our galaxy alone: there is the pure mind-blowing number of exoplanets that orbit other stars in the habitable zone; in the entire universe there is an abundance of water, oxygen, carbon and all the other main elements that make up life as we know it; and life on Earth itself evolved relatively quickly after the formation of the solar system was completed. Anyhow, our current instruments do not yet allow us to detect life on other planets, but there is a whole lot of other information that we have been able to find out already. So let's have a closer look at exoplanets to better understand them. 
  • 85
  • 23 Apr 2025
Topic Review
Al-Hamed Equation in Modern Dynamics
This article discusses the Al-Hamed Equation, a unified mathematical framework for motion modeling with friction, and explores its potential applications in various engineering fields, such as robotics, spacecraft, and medical devices. The article provides an overview of the historical development of friction models, including the Coulomb model and Dahl model, and explains in detail the derivation of the Al-Hamed Equation and its stability analysis using Lyapunov theory. The article also evaluates the equation's performance in various applications and discusses its potential challenges and future research prospects. By providing a comprehensive insight into the Al-Hamed Equation, the article aims to shed light on the importance of this mathematical framework in improving the performance of smart mechanical systems.
  • 51
  • 21 Apr 2025
Topic Review
April 18: Albert Einstein Passed Away
On April 18, 1955, the world lost one of its greatest intellectual giants. Albert Einstein, the Nobel Prize-winning physicist whose theories reshaped modern science, passed away in Princeton, New Jersey, at the age of 76. His death marked not only the conclusion of an extraordinary life but also a turning point in 20th-century scientific history. Though his voice was silenced, his ideas continue to resonate through the cosmos.
  • 171
  • 17 Apr 2025
Topic Review
April 17: Apollo 13 Returns Safely
Apollo 13 was a 1970 NASA Moon mission that turned into a survival crisis after an oxygen tank explosion. The crew, aided by Mission Control, used the Lunar Module as a lifeboat and improvised fixes to return safely. Though the Moon landing was canceled, the mission became a landmark example of problem-solving under pressure.
  • 112
  • 17 Apr 2025
Topic Review
Al-Hamed Equation in Nuclear Fusion Energy
The Al-Hamed Equation is a novel formulation in nuclear physics that refines the calculation of energy released during nuclear fusion reactions by explicitly incorporating the mass of all secondary particles produced. This contrasts with traditional models, which primarily consider the mass difference between initial and final nuclei, leading to more accurate energy predictions, crucial for optimizing fusion reactor design and ensuring operational safety.
  • 90
  • 16 Apr 2025
Topic Review
Al-Hamed Electro-Nuclear Equation: Integrating Energy
This research introduces a new theoretical framework in nuclear physics, referred to as the Al-Hamed Electro-Nuclear Equation, which integrates electric input energy with nuclear mass-energy interactions. Unlike conventional models that consider nuclear energy as solely a function of mass difference, the Al-Hamed model incorporates the energy contribution from electric potentials and includes the cumulative mass of all particles resulting from the nuclear reaction. The proposed equation: E = [(Q × V) + (Δm - S) × c²] accounts for both electrical energy (via charge and voltage) and mass-energy transformations (considering secondary nuclear products such as neutrons, mesons, or photons). This dual approach provides a more comprehensive description of electro-nuclear interactions, especially in scenarios involving controlled fusion or electro-stimulated decay. The paper presents a comparative analysis with traditional equations, applies the model to practical scenarios, and discusses its implications for advanced reactor designs and high-efficiency energy systems.
  • 65
  • 11 Apr 2025
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