Shop

When I was your age ... Pluto was a *planet*. by Kip Stewart

T-Shirts & Hoodies

Style:
We Use American Apparel Sizing Chart
or
$26.59
Available to buy on…

When I was your age ... Pluto was a *planet*. by 


Poor old Pluto. Demoted from planet to dwarf planet, or worse … panetoid!

In 2006 the International Astronomical Union ruled that Pluto was no longer a planet, leaving just eight planets proper in our Solar System.

For the record, a planet is:
“A celestial body that (i) is in orbit around the Sun, (ii) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (iii) has cleared the neighbourhood around its orbit.” (IAU Resolution B5)

Pluto satisfies (i) and (ii), but not (iii): there are other things sharing its orbit around the Sun. Bigger planets, with stronger gravitational fields, plough everything else out of the way as they go around the Sun. Pluto is just too small to make that kind of impact.

Off you go now, Pluto. It’s been fun.

Tags

space, geek, nerd, planet, cool, science, astronomy, astro, pluto

I’m a physicist, science communicator, certified iNerd, lover of (and amateur dabbler in) design, and rabid fan of quality science. This is where quirky ideas, fun science, wearable geekery and occasional accidentally cool photography gather.

View Full Profile

Comments

  • MuscularTeeth
    MuscularTeethabout 5 years ago

    haha

  • skarayalcin
    skarayalcinabout 5 years ago

    lol this cracked me up! nice tshirt Kip

  • RCMdesigns
    RCMdesignsabout 5 years ago

    :) I like this

  • Kip Stewart
    Kip Stewartabout 5 years ago

    Yeah … you know you’re growing old(er), I’d say, when the Solar System itself changes.

  • retepk
    retepkalmost 5 years ago

    A ripper. Like it.

  • Joy Watson
    Joy Watsonover 3 years ago

    coool

  • tori yule
    tori yuleover 3 years ago

    very cool!

  • Meagan93
    Meagan93over 2 years ago

    Love it :)

  • Nadya Johnson
    Nadya Johnsonalmost 2 years ago

    Cool work! Hope you’ll add it to Cutting Edge!

  • Paulo van Breugel
    Paulo van Breugelalmost 2 years ago

    Love it.

desktop tablet-landscape content-width tablet-portrait workstream-4-across phone-landscape phone-portrait