June 28th 2026

Things from Today:

• Puff Ball Planets - Puff ball planets were mentioned, and I must confess, I did not know very much about this type of exoplanet! These planets have been in the media recently following the TESS (Transiting Exoplanet Survey Satellite) discovery of the "puffiest" puff ball planet yet!
  What makes these puff balls (or 'Super-puffs') so fascinating, are their incredibly low densities. The puffiest of the two most recently discovered puff balls (TOI-791 b) is roughly the same size as Jupiter, but has only 3% of Jupiter's mass. This means its density (the amount of mass per unit volume) is similar to that of candy floss!
  Scientists are still trying to understand how these planets form and maintain a state of extreme 'puffiness' - as no single theory seems to fit all known examples. Something like a 'Hot Jupiter' is inflated to great size by the extreme heating from its parent star (gasses expand when heated), but not all puff balls are near enough to their parent star for this mechanism to be sufficient. In fact, the two most recent puff balls discovered (TOI-791 b and TOI-791 c) are both much further from their parent star than would normally be expected.

• Are we alone in the Universe? - This is a HUGE question. One that divides opinion, and fires up the imagination! I am a bit of a fence-sitter on this topic... In my view, we know so little about the origins of life on the Earth, that extrapolating to the wider cosmos (even given the enormous statistical weight of the vast number of planets in the observable universe) is very difficult. Biologists tell us that all life on Earth is descended from a single common ancestor (LUCA - the Last Universal Common Ancestor), which means that it is possible that life has only every emerged once in the history of our planet. When you look back far enough, to the origins of life, it really becomes a matter of physics and chemistry, rather than biology. Before you can have self replicating organisms, you need self replicating molecules - and we have no idea what sort of naturally occurring chemical processes would create molecules that can recreate themselves.
  In my view: It is entirely plausible that the circumstances required to form these self-replicating molecules and allow the complexities of even the simplest life forms to emerge from them, are so cosmically unlikely that we really may be the exception in an otherwise barren Universe.

• Dawid's Astrophotography - We were lucky to be joined by Southend based astrophotographer, Dawid Glawdzin, who kindly shared some of his fantastic astrophotography. Dawid posts his inspiring photographs to Instagram, so do take a look and give him a follow!

Extra Reading:

• [Article] Can giant space mirrors boost green energy on Earth? - Kaia Glickman (Nature)

• [Article] Thermodynamic Computers Go With the (Energy) Flow - Philip Ball (Quanta Magazine)

Extra Watching / Listening:

• [Video] General relativity from first principles - Adam Brown (Dwarkesh Patel YouTube Chanel)

• [Video] We May Never Understand Reality - Sean Carroll (New Scientist) 

Homework

This 'homework' is recurring, and one I like to set my own students (and try to stick to myself!):

1. Learn something new everyday.

2. Share what you know with someone else.

3. Look at the world and "think like a Martian".

If you learn something interesting, I would love to hear about it! Tell me about it next time or drop me an email!

spacetime-sundays@science-on-sea.com