We cannot see the Milky Way like we do other galaxies, and that’s because we live inside of it. Although we can peer along its edge while embedded in its disk, we cannot see what it looks like face-on. This is really annoying to astronomers, and akin to a cartographer who wants to make a map of their neighborhood, but is stuck in their house.In a study published today in Science, a team of researchers directly measured the distance to a star-forming region on the far side of the Milky Way, shattering the previous record for a direct distance measurement within our galaxy. According to the study’s lead author, Alberto Sanna of the Max-Planck Institute for Radio Astronomy (MPIfr), “This means that, using the VLBA, we now can accurately map the whole extent of our galaxy.”Previous attempts to observe and accurately map the opposite side of the Milky Way have mainly failed because of interloping interstellar dust in the galactic plane, which blocks optical light from reaching us. But, unlike optical light, radio waves can pass unimpeded through the interstellar dust.For this study, the researchers used the National Science Foundation’s Very Long Baseline Array (VLBA) to take observations in radio wavelengths. The VLBA is not just one telescope, but instead 10 identical 82-foot (25 meters) radio antennas scattered across North America, Hawaii, and the Caribbean. When linked together, these antennas form a massive interferometer with a nearly 5,000-mile (8,000 kilometer) baseline, giving the VLBA enough resolving power to spot a baseball on the Moon.