Earth’s magnetic field protects and makes our planet habitable by stopping harmful high-energy particles from space, including from the Sun. The source of this magnetic field is the core at the center of our planet.
The island of Santorini in the Mediterranean has attracted people for millennia. Today, it feels magical to watch the sun set from cliffs over the deep bay, surrounded by cobalt blue churches and whitewashed houses. This mystical place attracts about 2 million tourists per year, making it one of the top destinations in Greece.
The New Horizons spacecraft, which flew past Pluto in 2015, successfully completed a flyby of “Ultima Thule”, an object in the Kuiper belt of bodies beyond Neptune on January 1, 2019. The name Ultima Thule, signifying a distant unknown place, is fitting but it is currently just a nickname pending formal naming. The official names of the body and of the features on its surface will eventually be allocated (this could take years) by the International Astronomical Union (IAU), which celebrates its centenary in 2019.
Mount Agung in Bali has been thrusting ash thousands of feet into the sky for almost two weeks. Lava is burbling at the volcano’s peak. Indonesian authorities have ordered evacuations around Agung, while tourists are stranded at the closed airport. The volcano’s flanks are bulging from magma trying to push its way out, and earthquake frequency has been increasing.
Ethiopia tends to conjure images of sprawling dusty deserts, bustling streets in Addis Ababa or the precipitous cliffs of the Simien Mountains – possibly with a distance runner bounding along in the background. Yet the country is also one of the most volcanically active on Earth, thanks to Africa’s Great Rift Valley, which runs right through its heart.
The Earth has been the blue planet for as many as 3.8 billion years. Ancient sedimentary rock deposits and lava that cooled into characteristic pillow shapes provide irrefutable evidence that liquid water has existed at the Earth’s surface for at least this long. But given how many barren rocks there are in the galaxy, Earth’s abundant oceans raise the question of where all that water came from.