Month: April 2021

In recent years, cosmologists have been faced with a crisis: The universe is expanding, but no one can agree on how fast it’s moving away from us. That’s because different ways of measuring the Hubble constant, a fundamental parameter that describes this expansion, have produced conflicting results.  But a single, lucky observation of what are known as dark sirens — black holes or neutron stars whose crashes can be picked up by gravitational wave detectors on Earth but remain invisible to ordinary telescopes — could help resolve this tension.  As…

We’ll have to wait a bit longer to see the first Mars helicopter lift off. NASA had originally aimed to conduct the first Red Planet flight of its Ingenuity helicopter — the first-ever powered flight on a world beyond Earth — on Sunday (April 11). A high-speed rotor-spinning test on Friday (April 9) didn’t go as planned, however, pushing the debut back until Wednesday (April 14) at the earliest. Now, after analyzing the issue over the weekend, the Ingenuity team has concluded “that minor modification and reinstallation of Ingenuity’s flight…

[embedded content] SpaceX is moving on quickly from its latest fallen Starship prototype. Elon Musk’s company rolled out the newest Starship test vehicle, known as SN15 (“Serial No. 15”), its South Texas launch pad last Thursday (April 8), just over a week after its predecessor exploded during a high-altitude flight. That previous vehicle, SN11, performed well during most of its 6.2-mile-high (10 kilometers) flight on March 30 but suffered a serious problem while gearing up for landing. (SpaceX skipped the SN12, SN13 and SN14 iterations, going directly from SN11 to…