Consider the following observations. Classify each observation based on whether it is a real observation (a true statement of something we can actually see from Earth) or one that is not real (a statement of something that does not really occur as seen from Earth).

[Real:true statements]

- Mercury goes through a full cycle of phases

- Moon rises in east, sets in west each day

- stars circle daily around north or south celestial pole

- positions of nearby stars shift slightly back and forth each year

- a distance galaxy rises in east, sets in west each day

[Not real:false statements]

- we sometimes see a crescent Jupiter

- a planet beyond Saturn rises in west, sets in east

Real:

-Mercury goes through a full cycle of phases

-Moon rises in east, sets in west each day.

-Stars circle daily around north or south celestial pole.

-Positions of nearby stars shift slightly back and forth each year

-A distance galaxy rises in east. sets in west each day

False:

-We sometimes see a crescent jupiter

-A planet beyond Saturn rises in west, sets in east.

Explanation:

Real:

-Mercury goes through a full cycle of phases.

Mercury has different phases seen from Earth according with the angle in which the light from the Sun is reflected in it as a consequence of the configuration of Earth, the Sun and the planet.

Similar to how moon phases are gotten.

-Moon rises in east, sets in west each day; - A distance galaxy rises in east. sets in west each day.

Earth rotates counter-clockwise in its own axis. That motion takes 24 hours to complete a whole cycle (which is known as a day).

Therefore, the rotation leads to an effect that the stars and any astronomical object (the moon or a distant galaxy) rise from the east and sets in the west each day.

-Stars circle daily around north or south celestial pole.

North and south celestial pole are the projections of north and south of the Earth in the sky.

The fact that the stars circle around the celestial poles is another consequence of the Earth's daily motion.

-Positions of nearby stars shift slightly back and forth each year.

The angle due to the change in position of a nearby object against the background stars is known as parallax.

This angle is gotten when the position of the object (in this case, the star) is measured in January and then in July according with the configuration of the Earth with respect to the Sun in those months.

False:

-A planet beyond Saturn rises in west, sets in east.

This is not possible to be seen from Earth because its rotation in its axis is counter-clockwise (as it was already discussed). In the other hand, if a person stands in Venus will see the stars, planets and any other astronomical object moving from west to east since it rotates in its axis clockwise.

-We sometimes see a crescent Jupiter.

Crescent phase is gotten in the moon, for example, when it is between the Sun and the Earth.

This is not possible to see from Earth in the case of Jupiter because it is far enough to not have the necessary configuration with Earth to get this phase.