A Quiz On Extraterrestrial Objects

Explanation
Comets and asteroids are not called "Far-Earth Objects (NEO)". NEOs, or Near-Earth Objects, refer to any celestial bodies that come within 1.3 astronomical units (AU) of Earth's orbit. This includes asteroids, comets, and other objects. Therefore, the given statement is false.

Explanation
Comets are celestial objects composed largely of ice, dust, and small rocky particles. As they approach the Sun, the heat causes the ice to vaporize, creating a glowing coma (a cloud of gas and dust) around the nucleus of the comet. This vaporization process also forms a tail that points away from the Sun due to solar radiation and the solar wind. Therefore, it is correct to say that comets are made up of icy bodies.

Explanation
The statement that asteroids come from the "Kupier Belt" is incorrect. Asteroids actually come from the asteroid belt, which is located between the orbits of Mars and Jupiter in our solar system. The Kuiper Belt, on the other hand, is a region beyond Neptune that is home to many icy objects, including dwarf planets like Pluto.

Explanation
Comets do not come from the "Main Comet Belt". Comets are believed to originate from two main regions in the outer solar system: the Kuiper Belt and the Oort Cloud. The Kuiper Belt is a region beyond Neptune's orbit that is home to many icy objects, including comets. The Oort Cloud is a hypothetical region even further from the Sun, where it is believed that comets originate from. Therefore, the statement that comets come from the "Main Comet Belt" is false.

Explanation
Comets are celestial bodies that have highly elliptical orbits. Unlike the nearly circular orbits of planets, comets follow elongated paths around the Sun. This is due to the gravitational influence of other celestial bodies, which causes their orbits to be highly elongated. As a result, comets spend most of their time in the outer regions of the solar system, but occasionally come close to the Sun, resulting in the formation of a visible coma and tail. Therefore, the statement "The orbit of a comet is highly elliptical" is true.

Explanation
The orbital period of a comet can vary greatly, ranging from 75 to over 100,000 years. This range is due to the highly elliptical and elongated orbits that comets have around the Sun. Some comets have shorter orbital periods, completing their journey around the Sun in a few decades, while others take thousands or even tens of thousands of years to complete a single orbit. The wide range in orbital periods is a result of factors such as the comet's initial velocity, distance from the Sun, and gravitational interactions with other celestial bodies.

Explanation
The correct answer is 1-100. The orbital period of an asteroid refers to the time it takes for the asteroid to complete one orbit around the sun. This period can vary depending on the size and distance of the asteroid from the sun. Generally, most asteroids have orbital periods ranging from 1 to 100 years. However, it is worth noting that there are some exceptions where the orbital period can be outside this range, ranging from 75 to over 100,000 years.

Explanation
Silicates are minerals that are commonly found in comets and asteroids. These minerals have a crystalline structure that allows them to reflect light effectively. Therefore, if a comet or asteroid contains more silicates, it will have a higher ability to reflect light. This is why the statement "More silicates allow a comet or asteroid to reflect light" is true.

Explanation
This statement is false. Comets and asteroids do orbit the sun. Comets are icy bodies that orbit the sun in highly elliptical paths, while asteroids are rocky bodies that also orbit the sun, but in more circular or elliptical paths. Both comets and asteroids are part of our solar system and are influenced by the gravitational pull of the sun.

Explanation
Asteroids are celestial bodies that are primarily composed of rocky fragments. These rocky fragments, also known as regolith, are remnants from the early formation of the solar system. They are made up of various types of rock, including silicate minerals and metals. The composition of asteroids can vary, but the majority of them are indeed made up of rocky materials. Therefore, the statement "Asteroids are made up of rocky fragments" is true.

Explanation
Long period comets do not come from the Kuiper Belt. Instead, they originate from the Oort Cloud, a region located much farther away from the Sun. The Kuiper Belt is a region in our solar system beyond Neptune where shorter period comets are believed to originate from. Therefore, the statement that long period comets come from the Kuiper Belt is false.

Explanation
Comet Halley is the most famous comet of the 20th century because it is visible from Earth every 76 years, making it one of the most well-known and studied comets. It was first observed in ancient times and has been documented throughout history, including its most recent appearance in 1986. Comet Halley is named after the English astronomer Edmond Halley, who accurately predicted its return based on previous observations. Its regular and predictable orbit, as well as its distinctive appearance and historical significance, have made Comet Halley the most famous comet of the 20th century.

Explanation
Comet Halley is the correct answer because it is the only known short period comet among the options provided. Short period comets have orbits that take less than 200 years to complete, while long period comets take more than 200 years. Comet Hale-Bopp, Comet ISON, and Comet Alvarez are all long period comets, so they are not the correct answer.

Explanation
Asteroids are also called minor planets because they are small celestial bodies that orbit the Sun, similar to planets but on a smaller scale. They are also referred to as planetoids, which further emphasizes their resemblance to planets. However, asteroids are not comets, as comets are icy bodies that develop a glowing coma and tail when they approach the Sun. Lastly, while asteroids can be composed of rock, labeling them simply as "rocks" would be an oversimplification of their nature and composition.

Explanation
The correct answer is Alvarez Hypothesis. The hypothesis made by Luis and Walter Alvarez is commonly known as the Alvarez Hypothesis. This hypothesis proposes that the mass extinction event that occurred at the end of the Cretaceous period, which led to the extinction of the dinosaurs, was caused by a large asteroid impact on Earth. This hypothesis is supported by evidence such as the discovery of a layer of iridium-rich sedimentary rock, known as the K-Pg boundary, which is believed to be the result of the impact.

Explanation
Comets and asteroids have an irregular shape. Unlike regular shapes such as spheres or cubes, comets and asteroids do not have a uniform structure. They are made up of various rocky and icy materials that have been formed through collisions and gravitational forces. This irregular shape is due to their formation processes and the lack of significant gravitational forces to shape them into more regular forms.

Explanation
The statement that short period comets come from the Main Asteroid Belt is false. Short period comets actually come from the Kuiper Belt, a region of the solar system beyond Neptune that is home to many icy bodies. The Main Asteroid Belt, on the other hand, is located between Mars and Jupiter and consists of rocky asteroids. Therefore, short period comets do not originate from the Main Asteroid Belt.

Explanation
Comets and asteroids move relatively slow when viewed from Earth because they are located far away in space. Their distance from Earth causes their apparent motion to appear slower compared to other celestial objects such as planets or stars. Additionally, comets and asteroids have elliptical orbits, which means they can spend a longer time in certain parts of their orbit where their motion appears slower.

Explanation
Silicates are a type of minerals that are composed of silicon and oxygen, along with other elements such as metals. This means that silicates do contain silicon, oxygen, and at least one metal, making the statement true.

Explanation
The correct answer is Stony Meteorites, Stony-iron Meteorites, and Iron Meteorites. These three types of meteorites are classified based on their composition. Stony meteorites are mostly made up of silicate minerals and can be further divided into chondrites and achondrites. Stony-iron meteorites contain a combination of silicate minerals and iron-nickel alloys. Iron meteorites, as the name suggests, are mainly composed of iron-nickel alloys. Each type of meteorite provides valuable information about the early solar system and its evolution.