Question
20. The following diagram part of the night sky, including the constellation Leo. The circles represent stars. The unshaded circles represent the changing positions of one celestial object over a period of a few weeks. The celestial object represented by the unshaded circles most likely is (1) a galaxy (3) Earth's moon (2) a planet (4) another star
Answer
4.3
(270 Votes)
Nia
Professional · Tutor for 6 years
Answer
To determine what the unshaded circles in the tree structure diagram represent, we need to consider the characteristics of the options given:1. A galaxy - Galaxies are vast collections of stars, gas, and dust. They do not change position in the sky over a period of a few weeks to the extent that would be noticeable with the naked eye. Their apparent motion is due to the rotation of the Earth and the Earth's orbit around the Sun, which causes all celestial objects to shift gradually over time. However, this shift is not significant over a few weeks.2. A planet - Planets in our solar system orbit the Sun and can be seen moving against the background of stars over time. This motion is called apparent retrograde motion, and it can be observed over a period of a few weeks or months. Planets can appear to move in a complex path, sometimes looping back on themselves, depending on the relative positions of the Earth and the planet in their orbits.3. Earth's moon - The Moon orbits Earth and its position changes noticeably each night. However, the Moon's path is relatively predictable and follows a certain pattern across the sky, moving eastward among the stars from night to night.4. Another star - Stars, excluding the Sun, are so far away that their positions relative to each other do not appear to change over a few weeks. Their apparent motion is similar to that of galaxies, primarily due to the Earth's rotation and orbit.Given the description that the unshaded circles represent the changing positions of one celestial object over a period of a few weeks, the most likely answer is:(2) a planetPlanets can show noticeable movement against the background of stars over a few weeks, which is consistent with the description of the unshaded circles in the diagram.Final Answer: (2) a planet