Stretch and Squash vs Star Guide

Stretch and Squash demonstrates how a passing gravitational wave would stretch and squash the distances between objects. Gravitational waves are ripples in the fabric of space-time. They are produced by violent cosmic events, such as the collision of black holes. These ripples then travel through the universe at the speed of light. If they pass through Earth they change the distance between objects ever so slightly. Gravitational wave detectors have been built to measure these waves using kilometer-sized laser interferometers. Stretch and Squash illustrates the different effects that gravitational waves in different polarisations would have on space. (Imagine the gravitational waves are passing straight through your computer screen!) The stretching and squashing is exaggerated visually in order to emphasise the effect.

Turn your phone into a real‑time planetarium. Star Guide helps you explore the night sky, identify stars and planets, and plan the best moments to look up—whether you’re stargazing tonight or previewing the sky months from now. Point your device upward to see what’s above you, switch on Augmented Reality (AR) for an immersive sky overlay, and explore celestial objects in 3D. Want to plan ahead? Travel through time to see how the sky changes in the past or future, and preview the view from different locations around the world. Key features • Live star finder & planetarium view Explore the night sky based on your position and direction. • Augmented Reality mode Overlay stars and planets on your camera view for easy identification. • 3D stars & planets Visualize objects in a more immersive way and explore in 3D. • Best viewing time notifications Get alerts for great stargazing moments and upcoming viewing opportunities. • 24‑hour sky motion preview See how a star moves and circles across the sky over a full day. • Past & future sky “time travel” Rewind to previous nights or fast‑forward to plan future observations. • Different locations Change your location to preview the sky from other places—perfect for trips. Great for • Casual stargazing from your backyard • Learning the night sky with an interactive planetarium • Planning the best time to spot planets • Exploring how the sky looks from other cities and countries Permissions (why they may be requested) • Location: improves sky accuracy for your current position • Camera: required for AR mode • Notifications: optional alerts for best viewing times Download Star Guide and start exploring the sky—right from your pocket.