Where are we now? Re-visiting the Digital Earth through human-centered virtual and augmented reality geovisualization environments The original Digital Earth concept, formulated by Al Gore (1998), is essentially a virtual reality system. In this (imagined) system, users are able to freely explore all possible recorded knowledge or information about the Earth though an interactive interface. While we imagine such an interface primarily as visual for now, it can be expected that in the future other senses will be engaged, allowing for even more realistic virtual experiences. Even though 'realism' in the experience is desirable (i.e., it feels real), immersive experiences provided by visualization environments can go beyond reality, as they can be enhanced with queryable information. Of course one can also create fictitious experiences and simulations in such environments; including information about possible pasts (e.g., ancient Rome) and futures (e.g., a planned neighborhood); or spaces that we cannot (easily) directly experience (e.g., the Moon, Mars, other faraway spaces, under the oceans, core of the earth, etc.). At the time of this writing, there is a new wave of excitement across scientific communities and commercial markets about virtual, augmented and mixed reality technologies. Various forms of virtual reality (VR), such as stereoscopic displays, have seen such waves of excitement in the past (see Gartner's hype cycles, Linden and Fenn 2003). VR experiences appear to inspire people, but the excitement about VR displays tend to not last too long, perhaps partly because of the cumbersome hardware and the amount of involvement their setup requires. Current VR technologies offer better visual quality, somewhat easier-to-setup hardware, and more realistic virtual experiences; and are more affordable compared to previous generations. Nonetheless, only time will tell if VR will remain a mainstream display technology this time around. Augmented reality (AR) on the other hand, has only been experimental until recently, and is new to mainstream attention. Dedicated headsets, such as Microsoft Hololens (https://www.microsoft. com/en-us/hololens), MagicLeap (https://www.magicleap.com/) or similar, offer full state-of-theart AR experience with hand-and head-tracking, but importantly, there are already convincing and functioning AR applications for smartphones without having to wear a 'helmet' (e.g., see augmentedcreativity.ch, https://highlights.ikea.com/2017/ikea-place/). These AR applications for mobile phones make a strong case for the durability of AR, because this way, technology addresses a much wider audience. In other words, perhaps not many people will invest in dedicated headmounted displays, whereas many people already have smartphones. This prediction will depend on the developments of the next generation of smartphones, but we envision that with continued development of the 'Internet of Things' (IoT), such mobile AR applications will eventually allow us to point our device to any object containing a chip ...