Exoplanet’s visible light spectrum measured for the first time

For some 20 years, astronomers have been discovering exoplanets, or planets orbiting other stars, in various indirect fashions. These discoveries are just as scientific and valid as a visual observance, if not more so. But once in a while there’s a milestone that’s worth noting for the thrill as much as for the science. The first time we actually saw an exoplanet, i.e. directly imaged, in 2008 was one such example. Now we have the first official detection of an exoplanet’s visible light spectrum, courtesy of the HARPS planet-hunting machine and the ESO’s 3.6-meter telescope at the La Silla Observatory in Chile.

The exoplanet in question orbits the star 51 Pegasi, and is roughly 50 light-years away from Earth in the constellation Pegasus. What also makes this discovery noteworthy is that this exoplanet, 51 Pegasi b, is the first one we ever discovered back in 1995 that orbits a normal star like the Sun. For amateur astronomers, 51 Pegasi itself has an apparent magnitude of 5.49 — meaning you can *just* about see it without binoculars or a telescope if you’re under dark skies. Fortunately, we have much more sophisticated instrumentation available to us than the naked eye:

Do stars make sound? Researchers say yes

Yet the above hasn’t stopped scientists from scanning the heavens looking for potential sounds. For example, NASA found that sound can exist in the form of electromagnetic vibrations that pulsate in similar wavelengths. When Voyager 1 finally crossed into interstellar space in 2013, NASA was able to put together and play the sound of plasma wave data, which functioned as a kind of proof that the crossing occurred. A report last year from Scientific American showed that you can convert the hail of cosmic radiation into audible ‘music’ tracks, in an effort to better understand phenomena like the solar wind. It’s even believed that ancient sound waves may have sculpted the way galaxies formed, and that black holes may produce sound waves (pictured right).For centuries, mankind has been fascinated with the possible sounds of the heavens. We know that sound doesn’t travel in the vacuum of space — by definition, and unlike light, sound needs a medium through which to travel. Sound results from the disturbance (or vibration) of the particles in that medium. That’s why you hear those stories about how space battles in movies have impossible sound effects, because you wouldn’t hear any of it if it were real.