The fully stacked Super Heavy first stage and Starship Spacecraft measure in at approximately 118 meters tall. This beast of an interplanetary transportation system is designed to deliver 100 tons of cargo to mars while achieving the lowest marginal launch cost in history. These lofty goals require a massive spacecraft to crash into the Martian atmosphere at 7.5 kilometers per a second and decelerate using aerodynamic forces punctuated by a rocket-powered, hover slam landing. Don’t forget about the return trip with Earth’s significantly denser atmosphere applying even more friction.

With such large forces at play, one of the key technological challenges is the spacecraft’s heat shield. Like a knight riding into battle, a heat shield provides protection at the expense of additional weight. This tradeoff is critical when cargo capacity equates to life sustaining supplies. After first exploring carbon fiber construction for its strength to weight ratio, SpaceX has hit on an audacious plan to reduce development cost and ensure reusability of the Starship; build a spaceship out of stainless steel that sweats methane on entry. With weight foremost on the mind of rocket scientist, the proposition of a steel spacecraft seems anti-intuitive. On further inspection, when you add up the reinforcement material required for carbon fiber connection points and the higher melting temperature of modern steel alloys, the proposed design reduces weight by requiring less conventional heat shield material on the spacecraft. Augmenting the cooling via transpiration effectively allows the Starship to regenerate much of its heat shield capacity by replenishing methane which is also used for rocket fuel. Think really shining metal with powers of regeneration. Did someone say Wolverine?

The Starship’s transpirational cooling system is meant to augment and protect a more traditional heat shield on the reentry side of the spacecraft. This system maximizes overall reusability of the spacecraft while minimizing weight. The fact that we can compare it to our favorite member of the x-men makes the whole proposition even cooler, no pun intended. Here’s to the Wolverine heat shield.

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A green 94 Jeep Cherokee was my first car. My father had purchased it as a daily driver and my brother had inherited it once the state mistakenly issued him a license to operate a motor vehicle. Along the extensive network of dirt roads that crisscrossed my town to the sand pits and obstacles that dotted the local dump, this jeep had taken a legendary beating. Songs were written about it…or at least they should have been. It was my first ride. Like teenage love, the whirring purr of the indestructible inline 6 strained my heart strings and the rugged solid axle steed delivered me to any destination under any conditions.

As time passed, and life flung me away to college living on the windy streets of Boston, we would still bump into each other from time to time. She had been relegated to the role of a laundry vehicle at my family business. I would visit home catching glimpses of my old friend, drivetrain running as dependable as ever, lugging mountains of sheets up steep hills that hammered on her near bullet-proof transmission as her body rotted around her leaving a path of rusted metal in its wake. It took time to truly appreciate my relationship with the XJ.

In retrospect, the Jeep Cherokee is somewhat of an enigma. American Motors Corporation had shoehorned the son of a tractor engine into a unibody chassis. The approach broke ranks with the standard body on frame design that was a staple of pretty much all car manufacturing until that time. In was the last new jeep produced by AMC before Chrysler swooped in. Envisioned as a capable alternative for suburban families, the XJ delivered something that stood the test of time. Design cues that drew heavily from the utilitarian requirements imparted on military jeeps of old, the near 90 degree angles and straight lines were juxtaposed with body proportions that almost universally defined the standard for the Sport Utility Vehicle concept the XJ had authored with its birth. Like a beautiful final offering, the Jeep Cherokee screamed, “I was here” into the howling winds of progress and assimilation.

With an astonishing production run of 2.3 million units from 1983 to 2001, fuel efficiency standards put the last nail in the coffin of the XJ. Today they can still be seen loyally waiting for their owners posing as an affordable and still dependable option for a heavily used car. The crown may be tarnished and the castle in ashes, but the legend never dies. Long live the king.

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