Galaxies

Depth perception is hard to achieve when looking out into space. For decades, two camps of astrophysicists have disagreed over the nature of the North Polar Spur, a radio-wave emitting arc above the Milky Way galaxy's plane. Was it close and relatively small? Or was it faraway and much more massive? New research utilizing X-ray mapping of the galaxy has helped clarify the existence of both so-called smaller Fermi bubbles and larger X-ray ones.

Astronomers discovered in the late 1990s that galaxies move apart faster over time, contradicting expectations that gravity should slow cosmic expansion. This has prompted the revival of the "cosmological constant," a type of repulsive gravity theorized by Albert Einstein.

Look around you. Where are you? Where is this place you are occupying? Somewhere in a room, maybe in a city on a continent on a planet orbiting a star in a galaxy among billions. But… where is all of that?

Though it makes up about 25% of the universe, dark matter can't be seen directly; its existence is inferred through its gravitational effects, like the unexpectedly fast rotation of galaxies. The concept began in 1933 but gained wide acceptance after Vera Rubin’s galaxy rotation studies in the 1970s.

In 2011, three scientists won the Nobel prize for discovering “dark energy”, which they believed to be responsible for the accelerated expansion of the universe. But recently a group of astrophysicists from the University of Canterbury challenged this prevailing notion, and suggested that the original model is incorrect. This article details their alternative "timescape” model and dives into the debate about dark energy’s existence.

The collection includes illustrations and images of aurorae, planets, stars, galaxies, stellar nurseries, star clusters, exoplanets, quasars and black holes. Mission photography of astronauts, shuttles and telescopes is also featured.

The theory of general relativity, widely regarded as Einstein's most significant accomplishment, posits that mass and energy bend space and slow down time. One consequence is that massive objects, such as black holes, bend spacetime so much that light coming from behind the object wraps back around it.

Previously considered a near certainty, research data from Hubble and GAIA have reduced the likelihood of a collision and merger between the two galaxies. Instead, the data suggests the Milky Way will absorb the Large Magellanic Cloud, a dwarf galaxy, in the next two billion years.

She discovered that stars on the outer edges of galaxies were orbiting much faster than expected based on visible matter alone, implying the presence of unseen mass exerting gravitational force. Without dark matter, the outer stars in galaxies would fly off into space instead of staying in orbit.

Discovered by the Webb Telescope in 2022, Maise’s Galaxy (named after the nine-year-old daughter of the scientist who discovered it) was found as part of a survey of a section of the universe known as the Extended Growth Strip, home to thousands of galaxies. This video takes you from Earth to Maise’s galaxy, formed roughly 300 million years after the birth of the universe.