Since 1990, the Hubble Space Telescope has provided scientists with an incredible view of the universe, offering well over 1 million observations. In a recent release, NASA has introduced “Hubble Focus: The Dark Universe,” a free e-book that delves into what the Hubble mission has taught scientists about dark matter and dark energy, challenging long-standing theories.

Dark matter, a mysterious substance that cannot be seen, is believed to comprise the majority of the mass of the universe. Unlike normal matter, it is invisible and largely undetectable through traditional means. Scientists estimate that dark matter makes up 27 percent of the universe, while dark energy, responsible for the universe’s expansion, makes up 68 percent.

Equipped with powerful instruments, the Hubble Space Telescope can detect objects that are invisible to the human eye. This data has revolutionized our understanding of the invisible universe, sometimes posing challenges to existing cosmological models. “Hubble Focus: The Dark Universe” highlights key discoveries made possible by the Hubble mission, providing plain English explanations and stunning visuals.

The e-book also features expert quotes and links to videos exploring topics like the Hubble constant, the rate of the universe’s expansion. Hubble operations project scientist Ken Carpenter expressed excitement about the book, stating, “Much remains to be done, but this book will give you a front row seat to what’s been happening in this quest.” This volume is the fifth in a series of similar books that detail the Hubble mission and its groundbreaking discoveries.

For those eager to learn more about the enigmatic forces at play in the universe, “Hubble Focus: The Dark Universe” can be downloaded in PDF or EPUB format at bit.ly/hubblebook.