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1. Comet, asteroids and meteors

2. Have you experience observing the night sky and hoping for a falling star and making a wish?

3. Comets A comet is a fuzzy, luminous big dirty snowball composed of gas, rock, and dust wrapped around a big ball of ice. Aka “Dirty snow balls” Comets is composed ice, frozen gases, and organic compounds

4. Origin of the Comets Comets are usually found in Kuiper belt and Oort cloud. Kuiper belt a vast, donut-shaped disk of icy bodies and leftover materials from the solar system's formation, located beyond the orbit of Neptune .

5. Kuiper belt

6. Origin of the Comets Oort cloud  - a giant spherical shell surrounding the Sun, planets and Kuiper Belt Objects and the area which is located beyond the orbit of the Dwarf planet Pluto.

7. Oort cloud

8. Anatomy of a Comet

9. Anatomy of a comet It is the central solid part of the comet. The nucleus occupies the central position, also known as the core. It is composed or ice gas and dust NUCLEUS

10. Anatomy of a comet This is the bright, hazy atmosphere that forms around the nucleus when the comet nears the Sun. Together, the nucleus and coma form the head of the comet.  COMA

11. Anatomy of a comet It is the hydrogen gas surrounds the coma of the comet or  invisible layer of hydrogen gas that surrounds the coma.  HYDROGEN ENVELOPE

12. Anatomy of a comet It is formed by radiation from the sun forces dust particles away from the coma .  DUST TAIL

13. Anatomy of a comet Aka as “gas or plasma tail” It is made up of electrically charged gas molecules that are pushed away from the nucleus by the solar wind. ION TAIL

14. TWO TYPES OF COMETS SHORT PERIOD COMET-it is a comet with an orbital period of less than 200 years . Usually found Kuiper Belt. EXAMPLE Forbes (6.3 years ) Kojima (7.85 years ) Halley’s comet (87 years )

15. TWO TYPES OF COMETS LONG PERIOD COMET-it is a comet with an orbital period of MORE than 200 years . Usually located at Oort cloud. EXAMPLE Hale-Bopp (2530-2533 years ) Hyakutake (17,000years ) Kohoutek (50,000 to 200,000years )

16. Importance of Comets The composition of a comet is important in helping scientists understand how Earth has liquid water , which in turn made the planet habitable . During Earth’s formation, scientists theorized that the planet must have been too hot to have liquid water on its surface. By studying comets’ orbits and the chemical composition of materials found in impact craters found all over Earth, soil and ice samples collected from drilling down Earth’s crust and marine layers, scientists theorized that the early impact of comets on Earth brought liquid water to the planet .

17. asteroids Asteroids, sometimes called minor planets , are rocky, airless remnants left over from the early formation of our solar system about 4.6 billion years ago. Most asteroids can be found orbiting the Sun between Mars and Jupiter within the main asteroid belt.

18. asteroids Compositions: Silicates (olivine and pyroxene) Iron Nickel

19. Asteroid belt a torus-shaped region in the solar system located between the orbits of Mars and Jupiter that contains millions of irregularly shaped solid bodies called asteroids .

20. Asteroid belt

21. Three types of asteroids The three main types of asteroids, categorized by their composition, are C-type (chondrites, S-type (silicaceous), and M-type (metallic).

22. Three types of asteroids C-type (Chondrite) Asteroids Composition:  Composed of clay and silicate rocks, rich in carbon. They can also contain water ice.  Appearance:  Dark-colored and less reflective.  Location:  Found mostly in the outer regions of the asteroid belt. 

23. Three types of asteroids S-type (Siliceous) Asteroids  Composition: Made up of silicate materials and nickel-iron. Origin: Likely formed from fragments of larger asteroids. Location: More common in the inner part of the asteroid belt.

24. Three types of asteroids M-type (Metallic) Asteroids Composition: Rich in metallic components, such as nickel-iron.  Origin: Believed to be the metallic cores of large planetesimals that were shattered by collisions.  The rarest of the three major types. 

25. Near earth asteroids (Nea’s) An asteroid or comet which passes close to the Earth's orbit. While most are harmless, NEAs are studied because some could pose a threat if they were to collide with Earth. NASA and other organizations track and monitor NEAs using telescopes and have established the  International Asteroid Warning Network (IAW N )   to coordinate efforts in understanding and mitigating potential impacts. 

26. Large asteroid hits earth The asteroid that impacted Earth during the Mesozoic era, causing the mass extinction of the non-avian dinosaurs, is named the  Chicxulub impactor . It struck off the coast of the Yucatán Peninsula in Mexico 66 million years ago, and the resulting impact crater is known as the Chicxulub crater. 

27. meteoroids  Meteoroids are space rocks that range in size from dust grains to small asteroids. This term only applies when these rocks while they are still in space. Most meteoroids are pieces of other, larger bodies that have been broken or blasted off.

28. meteors A space rock that hits the atmosphere of the Earth. It's also another word for a shooting star.   When meteoroids enter Earth's atmosphere, or that of another planet, at high speed and burn up, they're called meteors.

29. meteorites A meteorite is a rock from outer space that survives its trip through a planet's atmosphere and lands on the surface. These rocks are called meteoroids while in space, and they become meteors (or "shooting stars") when they enter the atmosphere and burn up. Most meteorites are fragments of asteroids, providing scientists with clues about the early solar system. 

30. Classification of meteorites

31. Largest meteorite’s The Hoba meteorite is  the largest known intact meteorite on Earth, weighing around 60 tons and located on the Hoba West farm in Namibia . The "El Chaco" meteorite is a massive iron meteorite from the Campo del Cielo impact event in Argentina. it is now the second-largest meteorite ever found on Earth, with the largest being the  Hoba meteorite . 

32. What are the differences among them?