What was earlier the Earth or the Solar System?

Recognizing that Genisis does not attempt to explain the creation of the physical universe is key. Genesis is only concerned with the unique preparations God made on this planet so that it could support life of all sorts and creating those lives including humans. The creation of all the universe is only briefly mentioned in the verse you cited Gen 1:1 In the beginning God created the heavens(everything in the universe that is beyond the earths crust) and the earth( the planet earth which was formless and desolate ) Gen 1:2 Then by the end of the first chapter a brief synopsis on the development of the planet takes place up too and including human life.The bible is a book about humans their rise and Fall and the plan of redemption. It does not attempt to explain how or in what order the various parts of the universe came about.. One brief fact to ponder is the fact that we can see light from the Andromeda Nebula a galaxy that is over 2.5million light years away. That means that it took over2.5million years for the light to reach the observable heavens we see when we look up at night. The universe and planet are very old and the bible comments very little on the specifics. Source. https://www.google.com/search?q=andromeda+nebula&ie=UTF-8&oe=UTF-8&hl=en-us&client=safari

Creationists rarely think about the planets of the solar system. As we see at a site that calls itself YEC Headquarters, science is likely to "redefine the truth", and planets tend to make science the focus of discussion. This YEC site does not tell us what Young Earth Creationists think did happen, but only that scientists are wrong about the origin of the planets. Answersingenesis, probably the most widely read YEC site mentions planets only in so far as to claim scientific evidence that the world is only thousands of years old; once again avoiding the issue of just when the planets were created. The implication is that the answer is in the Bible and we need not consider any other explanations.

The Bible's first creation story (Genesis 1:1-2:4a) can be read as covering every aspect of God's creation, with nothing omitted, so there must be a reference to the creation of the planets. It begins with the earth alone, so just a cold and lonely rock floating aimlessly through space. The planets are lights in the sky above, so the biblical creation of the planets of the solar system (or for that matter the planets of other stars) is to be found in Genesis 1:14-15:

And God said, Let there be lights in the firmament of the heaven to divide the day from the night; and let them be for signs, and for seasons, and for days, and years: And let them be for lights in the firmament of the heaven to give light upon the earth: and it was so.

Since creationists regard the second creation story (Genesis 2:4b-25) as a retelling of part of the first creation story, we know from the biblical genealogies that the creation of man can only have taken place around 4000 BCE. The planets were created on the fourth day. For Young Earth Creationists and some Old Earth Creationists, these were literal days, so the planets are only around 6000 years old. In this hypothesis, the solar system is at least somewhat younger than the earth.

The gap theory is an attempt to harmonise biblical creation with the science of geology, on the basis that God created the earth (Genesis 1:1) millions, or even billions, of years ago. The gap exists between this initial creation and the events of Genesis 1:2 onwards. However, this does not move the creation of the sun, moon and stars - including the planets- as they are still created on the fourth day. That is resolved by some Old Earth Creationists by assuming that the Hebrew word used here for 'day' actually refers to an indefinite period of time, possibly millions of years. This is an untidy solution, open to many objections, but it provides a semblance of consistency with science. In this hypothesis, the solar system is younger than the earth.