First ever exomoon may have been found 4,000 light-years away

Researchers have announced the possible discovery of the first-ever exomoon — that is, the first moon spotted outside of our own solar system. The findings were made by researchers with Columbia University, which report good odds that the signal they detected reveals the presence of a moon orbiting a far away planet. The moon was found by looking for decreases in light from distant planets that results when the moon passes between it and the observing telescope.

The team used the Kepler Space Telescope as part of its mission to find an exomoon which, if real, orbits a planet near the massive star Kepler-1625. The grouping is located about 4,000 light-years from our own planet, and the possibility remains that the detected signals were caused by something other than a moon.

In order to determine whether the signals (of which three were observed) indicate the presence of a moon, the team wants to use Hubble to take a look at the region; this could happen as soon as this upcoming October. Using Hubble will provide better data on the observed light changes due to its greater power versus Kepler, which was used initially. Whether they'll ultimately get approval for using Hubble is yet to be seen.

The prospect of getting confirmation is exciting. Per the research, it seems this exomoon could be the size of Neptune with the planet it orbits measuring in somewhere around the size of Jupiter. A planet-sized moon would be an incredible discovery...assuming such a conclusion can be safely made. Hubble may reveal that the signal wasn't caused by a moon at all.

Verification about a planet-sized exomoon could open the doors to a whole new range of understanding about the worlds that lie beyond our solar system. Information about these worlds, though, isn't easily acquired. You can read what the researchers know at this point via this newly published study on the topic.