On February 4, 2021, the astronomy world will mark the 115th anniversary of the birth of Clyde Tombaugh — the man who discovered Pluto. To celebrate the occasion, Explore Scientific’s Explore Alliance is teaming up withAstronomyMagazine to host a special Pluto-themed Global Star Party at 7 p.m. CST.

  During the interactive livestream event, which will be simulcast free on Explore Scientific’s social media channels (connect at explorescientific.com/live), the editors and contributors to Astronomy Magazine as well as world-renowned astronomers and scientists will do a deep dive into all things Pluto — a solar system object that has only increased in notoriety since it was reclassified as a dwarf planet by the International Astronomical Union in 2006 — as well as its discoverer – Clyde Tombaugh.

Scheduled presenters on Pluto-themed topics will include:

• David Levy — renowned comet discoverer and author ofClyde Tombaugh: Discoverer of Planet Pluto

• David Eicher — editor-in-chief of Astronomy Magazine

• Alan Stern — the planetary scientist leadingNASA’s New Horizons mission to the Pluto system and the Kuiper Belt

• Alison Klesman, an associate editor at Astronomy Magazine who has completed years of research in the field of planetary science

  Although much of the event will be focused on Pluto, Scott Roberts and David Eicher will chat with other guests about the new era of spaceflight, science journalism, the legacy of Arecibo Observatory and more.

  This special event will be the 31st Global Star Party hosted by the Explore Alliance — the formal educational outreach organization supported by Explore Scientific — since the pandemic brought most in-person star party events to a halt last spring.

Source: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute/Alex Parker

This is the most accurate natural color images of Pluto taken by NASA's New Horizons spacecraft in 2015. These natural-color images result from refined calibration of data gathered by New Horizons' color Multispectral Visible Imaging Camera (MVIC). The processing creates images that would approximate the colors that the human eye would perceive, bringing them closer to “true color” than the images released near the encounter. This image was taken as New Horizons zipped toward Pluto and its moons on July 14, 2015, from a range of 22,025 miles (35,445) kilometers.

  In 1905, Percival Lowell, the successful businessman, mathematician and passionate amateur astronomer who founded Arizona’s Lowell Observatory, began an intense search for a ninth planet. Lowell had observed anomalies in the orbits of Neptune and Uranus that he believed could only be explained by the presence of another planet, which he dubbed “Planet X.” After more than a decade of observing and calculating, Lowell died in 1916 with his search for this elusive object unfulfilled.

  After a lengthy legal battle over Lowell’s estate, the long-shelved search for Planet X began again in 1929 when observatory newcomer Clyde Tombaugh was given the task of continuing Lowell’s work. Tombaugh, who was raised on a farm in Kansas, could not afford college as a young man so he fed his avid interest in astronomy by building his own telescopes out of old equipment parts and mirrors and lenses that he ground himself. He sent detailed drawings he had made of his observations of Jupiter and Mars to the Arizona observatory for feedback and was quickly offered a position instead. Tombaugh embraced the monotonous and painstaking task of scouring the skies for Lowell’s theorized Planet X. The search involved surveying portions of the sky by using a camera to take photos of the same section of sky one week apart and then meticulously analyzing them for any signs of movement in the objects. Tombaugh used a blink comparator that quickly flipped back and forth between the photographs to look for movement. On February 18th, 1930, he found what he was looking for when studying plates that had been taken on January 23rd and January 29th. The discovery of Planet X was confirmed and then announced on March 13, which was Lowell’s birthday.

  Needing to name the new planet, the observatory sent out a call for suggestions. After hearing about the discovery of this long-hidden planet from her grandfather, Venetia Burney, an 11-year-old girl from England, said it should be named for Pluto, the Roman god of the underworld. Her grandfather forwarded the suggestion on and it was soon selected.