NASA's Planetary Protection Officer

By Paula Johanson

There's been a new job posting at NASA, for a Planetary Protection Officer.

Sounds like something from the film Men In Black, doesn't it? But for NASA, planetary protection isn't so much about people resisting invasion by giant space bugs. It's about tiny germs.

NASA needs to avoid "organic-constituent and biological contamination in human and robotic space exploration." Policies for planetary protection apply to all space flight missions, whether they might carry Earth microbes or bring back microbes in samples from comets and asteroids. The posting lasts three to five years before someone else will be hired.

"It is not a new post," wrote reporter Andy Hayes for Sky News. Click here to read his article. He went on to add:

The current holder, Catharine Conley, was presented with a pair of sunglasses on her first day in the job back in 2006 - bringing to mind Tommy Lee Jones and Will Smith in Men in Black.

Dr Conley told the New York Times in 2015 that she was keen to keep Mars from becoming contaminated by anything from Earth.

"If we're going to look for life on Mars, it would be really kind of lame to bring Earth life and find that instead," Dr Conley said.

"So far, Mars is still pretty clean."

While most of the people applying for the position already work at NASA in some capacity, one of the first applicants was a civilian. Nine-year-old Jack Davis sent his letter of application, and it was well-received. The director of NASA's planetary science division, Dr James L. Green, wrote him an encouraging reply and you can read both letters at this link.

The Kiss Connection in Spacecraft

By Paula Johanson

If you've ever wondered what connection could there possibly be between chocolate and the space program, well, there is one. According to Colonel Chris Hadfield, the Canadian astronaut, it's the shape of a Hershey's Kiss.

On December 12, Hadfield posted on Facebook a picture of four spaceships, comparing the shape of the re-entry modules. All four have a similar shape. It's actually Hadfield's son Evan who manages most of Hadfield's social media posting, and he does so with grace and efficiency.

The Hadfields wrote a caption for the image:

The natural shape of spaceships. Apollo vs NASA's current fleet under construction. The Hershey's Kiss shape makes the spaceships inherently stable, and the broad flat bottom helps spread the blistering heat of re-entry. By moving the centre of gravity we can alter how the ships fly, and thus roll and steer them to both reduce g-load and land precisely.

It was Evan Hadfield who went on to add the following note:

All four of the modules shown have the same basic curved bottom, for the heat shield that protects the module while it returns to the Earth's surface. It is the shifting of the centre of gravity that allows it to creates lift – they shift it in the shaping of the capsule. Those two concepts are just different descriptions of the same thing.

One of the readers of Chris Hadfield’s Facebook page, Scott Corliss, had this to say about the curved bottoms of the re-entry modules:

The basic shape and curveture radius for the heat shields were worked out in the early 1960s by Harvey Allen, Max Faget and Caldwell Johnson (as noted in a book, Smithsonian Air & Space Collectors Edition, Fall 2013). Slide rule and engineering paper solutions still work today!

There's an adult discussion about the shape of the re-entry modules on the Space page on Reddit; for those who like to get a bit technical, click here.

And for those of any age who prefer a more hands-on approach to learning about space, there’s a link to a page here with instructions on how to make a spaceship-shaped treat for a space-themed party, complete with a Hershey's Kiss on top for a re-entry module. Now I know what to make for my brother's next birthday party -- he's been a spaceship fan since before the Apollo launches!