  Low-Earth orbit (LEO) satellite systems have been deemed a promising key
enabler for current 5G and the forthcoming 6G wireless networks. Such LEO
satellite constellations can provide worldwide three-dimensional coverage, high
data rate, and scalability, thus enabling truly ubiquitous connectivity. On the
other hand, another promising technology, reconfigurable intelligent surfaces
(RISs), has emerged with favorable features, such as flexible deployment, cost
& power efficiency, less transmission delay, noise-free nature, and in-band
full-duplex structure. LEO satellite networks have many practical imperfections
and limitations; however, exploiting RISs has been shown to be a potential
solution to overcome these challenges. Particularly, RISs can enhance link
quality, reduce the Doppler shift effect, and mitigate inter-/intra beam
interference. In this article, we delve into exploiting RISs in LEO satellite
networks. First, we present a holistic overview of LEO satellite communication
and RIS technology, highlighting potential benefits and challenges. Second, we
describe promising usage scenarios and applications in detail. Finally, we
discuss potential future directions and challenges on RIS-empowered LEO
networks, offering futuristic visions of the upcoming 6G era.
