Final answer:
Without additional information about the star close to planet Y, we cannot conclusively determine its properties. Generally, a yellow dwarf star is hotter than a red dwarf, but factors like type, mass, and luminosity must be considered to make a specific determination.
Step-by-step explanation:
The characteristics of stars vary widely, and their temperature, luminosity, and mass are interconnected. A critical understanding is that the most massive stars have the greatest gravity, allowing them to compress their centers significantly. This intense compression leads to high temperatures within and enables them to be extremely luminous with very hot surface temperatures. Conversely, stars with the lowest mass are cooler and less luminous. Therefore, if we're discussing a star close to a hypothetical planet Y, we would need more information to accurately determine whether the star is hotter, cooler, has more mass, or has less mass because it depends on various factors like type, mass, and luminosity.
However, typically, a yellow dwarf (like our Sun) is hotter than a red dwarf because the yellow light has a higher frequency, suggesting that if planet Y is orbiting around a yellow dwarf, the statement The star close to planet Y is hotter is most likely true. Yet, this is a generalization. To affirm this, we would need to compare the two stars' spectral types, luminosity, and other characteristics. Remember, some of the brightest stars in our sky are not necessarily the hottest, and some of the nearest stars to us are cooler than the Sun in temperature, yet may vary in luminosity.
Understanding this complexity is key in astrophysics, and these relationships are essential when evaluating the properties of stars in the cosmos.