2) Pluto’s icy ‘heart’. Credit: NASA/JHUAPL/SWRI)
𝑭𝒆𝒃𝒓𝒖𝒂𝒓𝒚 𝟏𝟖𝒕𝒉, 𝟏𝟗𝟑𝟎:
On this day 91 years ago, Clyde Tombaugh was helping in the search of a ninth planet, and he succeeded. He discovered a little planet which is what we now know as Pluto.
𝑯𝒐𝒘 𝒘𝒂𝒔 𝑷𝒍𝒖𝒕𝒐 𝒅𝒊𝒔𝒄𝒐𝒗𝒆𝒓𝒆𝒅?
🔭 A rich businessman named Percival Lowell, who had a passion for space and astronomy, created Lowell Observatory in Flagstaff, Arizona. When Clyde was 25, he was hired there to help out for the search of a ninth planet.
🔭 Clyde was comparing some photos of a star field taken a few days apart and saw an object drifting into the backdrop of stars, which was Pluto.
𝑾𝒉𝒚 𝒊𝒔 𝑷𝒍𝒖𝒕𝒐 𝒏𝒐 𝒍𝒐𝒏𝒈𝒆𝒓 𝒄𝒐𝒏𝒔𝒊𝒅𝒆𝒓𝒆𝒅 𝒂 𝒑𝒍𝒂𝒏𝒆𝒕?
🛰 The International Astronomical Union (IAU) has three criteria for a normal planet:
1. It is in orbit around the sun.
2. It has enough mass to form an almost round shape.
3. It should not share its orbital space with other gravitationally strong objects.
🛰 Pluto meets the first and second criteria, but does not meet the third. Therefore in 2006, it was demoted to a dwarf planet.
𝑪𝒐𝒐𝒍 𝒇𝒂𝒄𝒕𝒔 𝒂𝒃𝒐𝒖𝒕 𝑷𝒍𝒖𝒕𝒐 𝒂𝒏𝒅 𝒊𝒕𝒔 𝒅𝒊𝒔𝒄𝒐𝒗𝒆𝒓𝒆𝒓:
🌌 Pluto is smaller than some moons, including Earth’s. Pluto has five moons: Charon, Hydra, Nix, Kerberos, and Styx.
🌌 Pluto is one third water and two thirds rock.
🌌 Clyde Tombaugh has also discovered the asteroids 4755 Nicky, 2839 Annette, 7101 Haritina, and many more.
🌌 The asteroid 1604 Tombaugh was named after him but not discovered by him, though Clyde did name some asteroids after his wife, children, and grandchildren.
𝑫𝒊𝒅 𝒚𝒐𝒖 𝒌𝒏𝒐𝒘 𝒕𝒉𝒂𝒕 𝑷𝒍𝒖𝒕𝒐 𝒉𝒂𝒔 𝒂 ‘𝒉𝒆𝒂𝒓𝒕’?
💟 Cold as it may be, Pluto does indeed have a unique icy ‘heart’ on its surface!
💟 Tombaugh Regio, (named in honor of astronomer Clybe Tombaugh) is huge heart shaped area of frozen nitrogen on Pluto’s surface, that controls its atmosphere and climate by ‘pumping’ nitrogen winds aground the dwarf planet.