SPACEX, US NETWORK POOL SpaceX on Tuesday launched another Starship rocket, but passed up catching the booster with giant mechanical arms as Donald Trump joined Elon Musk to watch. Facebook Paul Goldschmidt, other former Cardinals look for new teams with MLB free agency underway However, findings published earlier this year by an international research collaboration of more than 900 scientists from around the globe yielded a major surprise. As the scientists analyzed how galaxies move, they found that the force pushing or pulling them around did not seem to be constant. Meteors from the Geminid meteor shower streak across the sky Dec. 14 above the Nicholas U. Mayall Telescope at Kitt Peak National Observatory, a program of NSF's NOIRLab in Tucson, Ariz. Rob Sparks, NSF's NOIRLab The same group published a new, broader set of analyses Tuesday that yielded a similar answer. "I did not think that such a result would happen in my lifetime," said Mustapha Ishak-Boushaki, a cosmologist at the University of Texas at Dallas who is part of the collaboration. Called the Dark Energy Spectroscopic Instrument, it uses a telescope based in Tucson, Arizona, to create a three-dimensional map of the universe's 11-billion-year history to see how galaxies clustered throughout time and across space. That gives scientists information about how the universe evolved and where it might be heading. The map they are building would not make sense if dark energy were a constant force, as it is theorized. Instead, the energy appears to be changing or weakening over time. If that is indeed the case, it would upend astronomers' standard cosmological model. It could mean that dark energy is very different than what scientists thought — or that there may be something else going on. "It's a time of great excitement, and also some head-scratching and confusion," said Bhuvnesh Jain, a cosmologist at the University of Pennsylvania who is not involved with the research. The collaboration's latest finding points to a possible explanation from an older theory: that across billions of years of cosmic history, the universe expanded and galaxies clustered as Einstein's general relativity predicted. The Dark Energy Spectroscopic Instrument, or DESI, makes observations in the night sky on the Nicholas U. Mayall 4-meter Telescope at Kitt Peak National Observatory in Tucson, Ariz. Peter Toman Tomas Slovinsky, NSF's NOIRLab The new findings aren't definitive. Astronomers say they need more data to overturn a theory that seemed to fit together so well. They hope observations from other telescopes and new analyses of the new data over the next few years will determine whether the current view of dark energy stands or falls. "The significance of this result right now is tantalizing," said Robert Caldwell, a physicist at Dartmouth College who is not involved with the research, "but it's not like a gold-plated measurement." There's a lot riding on the answer. Because dark energy is the biggest component of the universe, its behavior determines the universe's fate, explained David Spergel, an astrophysicist and president of the Simons Foundation. If dark energy is constant, the universe will continue to expand, forever getting colder and emptier. If it's growing in strength, the universe will expand so speedily, it'll destroy itself in what astronomers call the Big Rip. "Not to panic. If this is what's going on, it won't happen for billions of years," he said. "But we'd like to know about it." 50 images of the universe from the Hubble Space Telescope 50 images of the universe from the Hubble Space Telescope On April 24, 1990, the Space Shuttle Discovery launched, carrying the Hubble Space Telescope (HST, or just "Hubble"). This orbiting telescope was the first of NASA's Great Observatories. For more than 30 years, HST has provided astronomers with incredible scientific data on everything from solar system objects to some of the most distant galaxies in the cosmos. Hubble was named for American astronomer Edwin Hubble, who in the early 20th century helped establish that the universe is much bigger than the Milky Way and showed the cosmos is expanding. Stacker collected 50 Hubble images, taken between 1990 and 2020, that express both the beauty of the universe and important scientific knowledge. HST is a bus-sized satellite containing a 2.4-meter-diameter mirror for focusing light from distant objects, along with a suite of instruments for photography, measuring light intensity, and taking the spectrum of various astronomical sources. Hubble is primarily an optical telescope, viewing the cosmos in the same type of light we can see, and it also has the ability to see into the infrared and ultraviolet parts of the spectrum of light. The size of the telescope and its location above Earth's atmosphere (with its pesky weather and distortions from air currents) make HST one of the best optical telescopes still in operation. HST is jointly operated by NASA and the European Space Agency and was designed to be serviced by astronauts. Unfortunately, the Hubble needed to be repaired immediately after launch, when it turned out its mirror was slightly flawed. NASA astronauts installed additional mirrors to compensate for the flaws in 1993 and upgraded other scientific instruments on five different occasions, with the last upgrade being in 2009. Meanwhile, no plans are in the works to build an equivalent space telescope, so astronomers and nonscientists alike hope Hubble will continue to work indefinitely. Click on for 50 images of the universe as seen from the Hubble Space Telescope.