The common idea presented in both ‘our solar system: In-Depth’ & ‘Our Solar System’ is our solar system in detail.
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Both of them talk about the solar system, the sun, and its planets, their constituents, sequence of the location of the planets in reference to the sun, their formation and significance.
Besides the solar system, the former also talks about the Milky Way, its formation, the explosion of two supernovas that led to the formation of solar systems, and other constituents of the Milky Way - a spiral mass and our galaxy, one among many others in the big universe.
It also gives a reason behind the location of the first four planets near the sun and the gaseous and icy masses away from the sun.
It also talks about the other masses that are there in the Milky Way like the asteroids and comets.
A search engine is a program that searches/identify items in a database which corresponds to keywords specified by the user. A meta search engine is an online information retrieval tool that uses data of a web (search English) and that makes its own results. A subject directory is a service which offers a collection of links to the internet which is posted by creators. Hope this helped!
I think it’s C sorry If wrong
