The European Space Agency released a trove of data Monday on almost 2 billion stars in the Milky Way, collected by its Gaia space observatory in an effort to create the most accurate and complete map of our galaxy. Astronomers hope to use the data to understand better how stars are born and die, and how the Milky Way evolved over billions of years. The new data includes new information such as the age, mass, temperature and chemical composition of stars. This can be used, for example, to determine which stars were born in another galaxy and then migrated to the Milky Way. Also read: SpaceX launches 4 astronauts for NASA after private flight "This is an incredible gold mine for astronomy,” said Antonella Vallenari, who helped lead a consortium of 450 scientists and engineers who spent years turning the measurements collected by the space probe into usable data. Gaia was also able to detect more than 100,000 starquakes, which the ESA likened to large tsunamis that ripple across stars. They appear to make the stars blink and allow scientists to deduce their density, interior rotation and inside temperature, astrophysicist Conny Aerts said. Although it has only collected information on about 1% of the Milky Way's stars, the Gaia mission is already providing the basis for around 1,600 scientific publications a year. Project scientist Timo Prusti said the sheer number of stars observed makes it more likely that scientists will make very rare discoveries. “You have to observe a lot of objects in order to get the needle in the haystack,” he said. ESA chief Josef Aschbacher said having more data also allows astronomers to understand some of the forces at play in the galaxy, such as the way our own solar system is being thrown about inside the Milky Way. Also read: Space telescope launched on daring quest to behold 1st stars “It is enabling things that would never be possible without this large number of data,” he said. The Gaia data now being released also includes information on 800,000 binaries — stars that move in tandem with each other — as well as several new exoplanets, hundreds of thousands of asteroids in the solar system and millions of objects beyond our galaxy.

NASA is returning to sizzling Venus, our closest yet perhaps most overlooked neighbor, after decades of exploring other worlds. The space agency’s new administrator, Bill Nelson, announced two new robotic missions to the solar system’s hottest planet, during his first major address to employees Wednesday. Read:Chinese cargo spacecraft docks with orbital station “These two sister missions both aim to understand how Venus became an inferno-like world capable of melting lead at the surface,” Nelson said. One mission named DaVinci Plus will analyze the thick, cloudy Venusian atmosphere in an attempt to determine whether the inferno planet ever had an ocean and was possibly habitable. A small craft will plunge through the atmosphere to measure the gases. It will be the first U.S.-led mission to the Venusian atmosphere since 1978. The other mission, called Veritas, will seek a geologic history by mapping the rocky planet’s surface. Read:Forecast: 40% chance Earth to be hotter than Paris goal soon “It is astounding how little we know about Venus,” but the new missions will give fresh views of the planet’s atmosphere, made up mostly of carbon dioxide, down to the core, NASA scientist Tom Wagner said in a statement. “It will be as if we have rediscovered the planet.” NASA’s top science official, Thomas Zurbuchen, calls it “a new decade of Venus.” Each mission — launching sometime around 2028 to 2030 — will receive $500 million for development under NASA’s Discovery program. The missions beat out two other proposed projects, to Jupiter’s moon Io and Neptune’s icy moon Triton. The U.S. and the former Soviet Union sent multiple spacecraft to Venus in the early days of space exploration. NASA’s Mariner 2 performed the first successful flyby in 1962, and the Soviets’ Venera 7 made the first successful landing in 1970. Read: Cosmic 2-for-1: Total lunar eclipse combines with supermoon In 1989, NASA used a space shuttle to send its Magellan spacecraft into orbit around Venus. The European Space Agency put a spacecraft around Venus in 2006.