Astronomy, in general, is the study of celestial bodies, and the universe as a whole, excluding the earth. It includes the study of stars, planets, galaxies and other objects that are beyond the atmosphere of earth. The Bible does reference several objects, such as planets and constellations, found in what we today call space.
For example, the most studied star in astronomy, the sun, is directly mentioned at least 160 times in the King James Bible translation, with the moon referred to 51 times. During Biblical times, the only planets viewable from the earth were Mercury, Venus, Mars, Jupiter and Saturn. Some of these can be found in Scripture, not by the names we call them today, but through the false gods astronomy has associated with them.
Astronomy tells us that next to the sun and moon, the planet Venus is the brightest object we can see in the night sky. Its ability to reflect light is due to its close proximity to the sun and the highly reflective clouds of sulfuric acid that shroud it. Many times it can easily be seen just before sunrise, hence its reference in astronomy as the "morning star." It can even be viewed during the day, lending to it also being called the "day star."
There are allusions in the Bible to Christ being the morning star. Since Venus was the brightest of all the points of light in the sky the analogy would be that Christ would be the brightest (or have the preeminence) over the other heavenly bodies, which are the stars that correspond to angels (2Peter 1:19, Revelation 2:26, 28, 22:16).
According to a 1913 Catholic Encyclopedia article on Astronomy, the planet Saturn is directly referenced in the book of Amos. The Encyclopedia states, "Saturn is no less certainly represented by the star Kaiwan (called "Chiun" in the KJV Bible), adored by the reprobate Israelites in the desert (Amos 5:26)."
In Stephen's discourse just before his martyrdom, he mentions God's condemnation of ancient Israel's idolatrous worship of "your god Remphan" (Acts 7:43). Remphan was the Egyptian name for Saturn (JFB commentary on Amos 5:26).
Isaiah 65:11, according to the JFB commentary, alludes to Jupiter and Venus. The verse itself states, "But you who forsake the Lord, who forget My holy mountain, who prepare a table for Fortune, and who furnish the drink offering to Fate" (HBFV). The Hebrew word for "fortune" is Gad, which is an astronomy reference to the Babylonian god linked to Jupiter. The Hebrew word for "fate," which is Meni, is linked to the planet Venus.
The Bible also contains several other astronomy related references to constellations or groupings of stars. The book of Job mentions space related phenomena more than any other book. Constellations such as the Bear (Arcturus), Orion, and Pleiades are written about in Job 9:8 - 9, 38:31 - 33 and also Amos 5:8.
Modern astronomy tells us that the number of stars in the observable universe that exist (all objects whose light and other signals can reach the earth) is 300 sextillion (that's 3 followed by 23 zeros)! A 2016 study, published in "The Astrophysical Journal," estimated that at a minimum 2 TRILLION galaxies exist in the observable universe.
Given all of the above, it should therefore not be surprising that God, who created everything we find in space, mentions some of them in the Bible. He has graciously allowed us, through astronomy, to witness his handiwork and the power he lovingly wields.