The agency gave a rosy update on Artemis III, a test flight for its goal to return humans to the moon, but experts say the timeline is ambitious.

Pioneer 10 holds the titles for many “firsts”: It was NASA’s first mission to the outer planets, the first spacecraft to fly beyond Mars, the first to traverse the asteroid belt, and the first to fly past Jupiter. It was also the first spacecraft placed on a trajectory to escape the solar system into interstellarContinue reading "June 13, 1983: Pioneer 10 leaves solar system"

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The agency gave a rosy update on Artemis III, a test flight for its goal to return humans to the moon, but experts say the timeline is ambitious.

Does the fact that we see light from very distant galaxies prove that the one-way speed of light is finite? Dr. Jason Lisle responds to this question. The conventionality thesis plays a critical role in understanding the issue, suggesting that measurements usually assume an isotropic light speed.