Exoplanet Excursions: April 2015

Jon takes his brand new spaceship on a test flight to beautiful Kepler 438b.

For this trip, I’m going to need a bigger spaceship.

A
a
-
Image Credit: 
Mark Garlick
Credit: Illustration by Mark Garlick

The trusty old Cruiser Globe has been showing concerning signs of fragility as a result of the unfathomable lightyears travelled on our exoplanet excursions. So I’ve retired the Globe to the agricultural Lancashire barn where  it resides between trips – it’ll do grand for future quick hops to the Moon to watch Earthrise with a cup of tea.

My new vessel has similarities to the interior of Carl Sagan’s Ship of the Imagination from Cosmos, though it’s not quite as huge as the inside of that particular craft, which appeared like a cross between an aircraft carrier and Royale’s nightclub in Southport. My ship, named The Perihelion, is like a soft-top roadster version of Carl’s spaceship, with an impressive array of interstellar travel capabilities. Its exterior is less like a dandelion seed, more a hybrid of a Bob Lazar UFO and a Ford Capri.

The Perihelion’s maiden trip should be to somewhere familiar, so I’ll travel back to the constellation of Lyra where once I visited the stunningly beautiful world, Kepler 62e. It seems appropriate that this trip should be to the 1,000th Kepler world to be verified. Orbiting red dwarf star Kepler 438, 470 lightyears from us, is Earth-like planet Kepler 438b.

This rocky world is 1.12 times the size of Earth. Its parent star, being a red dwarf, is smaller and cooler than the Sun, so the habitable zone is comparatively close. It only takes 35.2 days for Kepler 438b to complete one orbit, a nice month-like period that’s pleasingly similar to that of our Moon.

From the surface of this world, the star Kepler 438 hardly seems like a dwarf: it looms imposingly large and scarlet, like a colossal, perfect sphere of volcanic magma. There’s 40 times more radiation reaching this planet’s surface than is the case with Earth. The surface light is far greater than we’d be used to on a midsummer day, but thankfully the Perihelion’s light balancers filter the powerful luminosity to a tolerable level.

Kepler 438b also receives a much stronger solar wind from its star than Earth does from the Sun. I’m hoping the planet’s atmosphere has a strong enough magnetic field to help it survive the ferocity of the satr’s highly energetic particles, which stream towards it as if shot out of a water cannon.

After the setting of the parent star, there’s an alluring orange glow to the night sky and behind me there’s a wonderful exoplanetary Belt of Venus. The curve of Kepler 438b casts a shadow into its own atmosphere. The ochre glow of the sky fades into the shadow curve of deep, oaky brown.

The great strength of the stellar wind, coupled with the robustness of the atmosphere and its magnetic field, gives rise to the most dazzlingly vivid alien aurora, with luminosity like mobile disco lasers hitting the wall of  a church hall. The indigo, crimson and fluorescent olive shades of this aurora have a brightness powerful enough to cast shadows. With hypnotic subtlety, these auroral shadows ripple against the alien terrain like the silhouetted lady from the title sequence from Roald Dahl’s Tales of the Unexpected.


Jon Culshaw is a comedian, impressionist and guest on The Sky at Night
This column appeared in the April 2015 issue of BBC Sky at Night Magazine
Like this article? Why not:
Exoplanet Excursions: March 2015
previous feature Article
Exoplanet Excursions: May 2015
next feature Article
We use cookies to improve your experience of our website. Cookies perform functions like recognising you each time you visit and delivering advertising messages that are relevant to you. Read more here