How it Started, How it’s Going

Science Definition Team work room, 2013. Photo by S. Milkovich

In February 2013, I had a new routine: upon arrival at JPL each morning, poke my head into a small corner room in the Flight Projects building before heading to my office across Lab.  Over the next few months, the walls – and eventually windows – of that small room were coated in pages and pages of powerpoint printouts.

We rearranged those pages over and over during the next few months, standing back and staring at the wall as we continually asked ourselves: did the chain of logic ring true? was there a missing logical step? If so, what was it and who on the team could champion it?

Eventually we wrote up the report of the Mars 2020 Science Definition Team, setting out the scientific purpose of the next NASA flagship mission to the surface of Mars, but not before a giant word document full of 15 people’s many track changes destroyed my harddrive.

I carried the torch of “scientifically selected and returnable samples” through rover development and into implementation. Sometimes I was arguing with the engineers who didn’t understand why this rover had to be so operationally efficient. Sometimes I was arguing with the scientists who wanted to fall back upon exploration and operations styles of previous rovers. But I tried to hold true to the vision of the science definition team: focus on the technical needs to support collection of scientifically returnable samples, because of the revolution of understanding of our place in the universe that could result.

As chronic health issues and work politics started taking over, I handed the torch over to members of the team I had assembled, a mix of scientists interested in engineering and engineers who wanted to enable science. Proud of the people whom I brought onto my team who rose to the challenge. Some of them had stumbling blocks thrown in their way, but they carried the torch of scientifically selected returnable samples into other corners of the mission.

In February 2020 the rover was sent to Florida to prepare for launch, and in March 2020 we all went home. My pre-existing health conditions make us all on high alert, and I can count on one hand the number of times I left the house in the next year.

July 2020 we watched the launch from home over the internet – waking my young son up at 4 am, he told me “I didn’t sign up for this.” I wept because it successfully launched, I wept because I couldn’t be with the science team members from the US and Spain and France and Norway to celebrate after all my years of championing them to the JPL engineers, and I wept because I had poured all my energies into this inanimate project for years and wasn’t sure what I had to show for it.

On 18 February 2021 we landed on Mars. Last time I was part of a team that landed on Mars, I was surrounded by the Curiosity Science team and feeling their energy in the room. The time before that, I sat in a hotel in NYC with the members of the Caltech-Occidental Concert Band, and clutched a pillow as we watched Mars Phoenix land before heading out to perform at Carnegie Hall. This time, the energy was at a remove. Everything seems at a remove these days – the reality of Perseverance on Mars, the discussions  of the science team about what to do next with the rover. I sit in the home office that I share with my spouse as the pandemic rages around us. Reality is masking and hand sanitizer and vaccines and school policies, and hoping that our parents stay healthy.

February 2022: in the last year, we have explored the floor of Jezero Crater, and discovered its history of lava flows interacting with water. We have collected samples and are getting ready to drive to the Jezero Delta. I am filled with memories of senior JPL staff standing up in reviews, telling us that there was no way that we’d be able to collect a cache in one Mars year (two Earth years). That we couldn’t keep the science team focused, that we’d have too much in-fighting and be too distracted by the interesting rocks we encountered. And yet here we are, well on our way.

One upon a time, this rover was paper printouts on a wall, a word document with so many track changes that it crashed my computer and made me get a new harddrive. When I showed up to graduate school in 2000 I was handed a book called “Water on Mars” by Dr. Mike Carr as a foundational text to orient myself. Thirteen years later as we wrapped up the Science Definition Team Report, Mike himself told me that he’d been on Mars Sample Return concept discussions for decades but this was the first one that he thought might actually make it happen.

Someone from the Science Definition Team sent me chocolates after we submitted our report, and I still don’t know who.

We have an actual rover on the surface of Mars.

The science team is prospering and they don’t need me anymore; I hold new science team member’s hands and give them the information they need to find the data and join the conversations. There is strength and joy in setting others up for success, and in watching them succeed. There is despair in standing on the sidelines and watching others march past full of purpose.

Whatever happens in the future, whatever paths I may travel, I will never forget that once upon a time there was a powerpoint file on my laptop that grew into a rover on Mars, and potentially to rocks brought back to Earth to teach us about the origin of life.

We came in peace – and complexity – for all humankind.

Dr Sarah Milkovich

Feb 18 2022

This image was acquired on Feb. 17, 2022 (Sol 354) by the Perseverance Rover, Jezero Crater, Mars. NASA/JPL-Caltech/ASU.

Cores of Rock

I stand in the back corner of the small elevator, holding my son’s hand as we rattle our way down and slightly sideways to the 27th level. The tour guide shines her light on the gaps in the elevator cage door so that we can see the layers of rock interrupted by the inky darkness of closed levels. The previous time I’ve been in this elevator, there were no lights, and I stood next to my grandfather’s wheelchair. This time I am with my parents, my husband, my son, and a handful of other tourists. The elevator stops half a mile underground, and we step out.

This is the Tower-Soudan Underground Mine in Minnesota, once the oldest and deepest of Minnesota’s iron mines and now a state park. My great-grandfather died while working in a neighboring mine, and my grandfather left high school to work in that mine in order to support his mother and sisters. This is a pilgrimage to a place that represents one of the foundational stories of my childhood, and an attempt to convey to my young son where his family came from.

The thread of these rocks is woven into the fabric of my life. My grandparents’ house was right on the edge of an open-pit iron mine, and as a kid my dad sold little containers of rocks from the mine to visitors who stopped where the road ended to look into the pit. He brought an enthusiasm for geology to his marriage, and my mom picked it up and ran with it. I grew up hearing about how the rocks of my hometown in upstate New York were laid down in shallow seas and later shaped by ice sheets flowing across the surface. The rocks that I sat on when visiting the northeastern Minnesota shoreline were remnants of volcanic eruptions from over a billion years ago. The rocks I traveled past on our drives to my boarding school in New Hampshire once were attached to Africa. Is it any wonder that I ended up in a geology-adjacent career?

I remember being fascinated by the collection of rocks that my parents accumulated over the years. I, too, now pick up rocks wherever I go and display them around my house. One of my personal treasures, though, is not one that I carried back from a hike or purchased at a rock show. It is the (suprisingly heavy) core sample of iron from thousands of feet underground, from the iron mine. My grandfather brought it to the surface for my dad, who gave it to me.

Right now, there is a robot so much further away – millions of miles instead of thousands of feet – who is also collecting core samples that may someday be brought to the Earth’s surface. I have taken that tiny thread from my family and woven it into the vast tapestry that is the Mars Perseverance rover. Thousands of people all around the world worked together to create this rover, and we all brought our intellectual experience as well as our emotional resilience to the project. The Perseverance rover is many things (large, complex, ambitious), but I like to think that it includes that small, sparkling thread – a faint echo that resounds from outer space to the underground mine. I wish my grandfather and great-grandfather could hear it.

A Rebalancing

Like everyone else fortunate to have a steady paycheck that allows them to shelter-in-place this last year and a half, I’ve been doing an internal assessment of sorts. If I define success on my own terms, what does it look like? How do I define myself outside of my job? If I step to the side of expectations and let them pass me by, what would my life look like? What would make me feel like a whole person, rather than an entity doing a specific job? Even if that job is “rocket scientist” – on a day-to-day level, I was not valuing the person, only the ability to do a job that by its very nature doesn’t have measurable benchmarks. Furthermore, my particular niche within the world of rocket science tends to be invisible – the less others notice big problems and focus on smaller complaints, the better I am doing my job.

Who am I trying to prove anything to anymore? I know my own value; I am good at my job, but I am not just the job.

It has been one year since I went part-time at work. Since I have allowed myself to define who I am in other ways. Amazing as the identity of rocket scientist is, it ultimately became a cage. It turns out that I am many things: I am an artist. I am a storyteller. I am a mother. I am disabled. I am a good and loyal friend. I am an explorer. I continue to create a safe haven for my loved ones in a time of turmoil and despair. I have the spirit of a pagan inside the soul of a scientist.

Once upon a time I was going to use this blog as part of my science storytelling. Before the day-to-day grind of my job consumed me and I lost joy in what I did. Now I’m going to try to find that joy again, and start telling stories once more.

welp gonna lock that one down

My previous post, which was a form of semi-public grieving for some health and career stuff that’s been going on, has turned up in web searches related to the rover – so I’ve password protected it. Folks who know me and want to read it can email me for the password. Thank you to everyone who has reached out for their love & support.

Ending on a HiNote

In 2009, I became the HiRISE investigation scientist for Mars Reconnaissance Orbiter, a role I’ve described in a few other places.

I’ve seen the team through safe modes, loss of one of their CCDs, two solar conjunctions, imaging MSL on the parachute, figuring out creative ways to deal with constraints that MRO’s job relaying science data from Curiosity places on HiRISE’s imaging capabilities, imaging comets, and lots and lots of glorious images of Mars.

Along the way, I’ve made a lot of friends, both with the MRO operations team at JPL and the HiRISE team. The HiRISE operations team is based in Tucson, at the University of Arizona. In honor of their camera, they put “Hi” in front of as many mailing lists and processes or scripts as they can (HiCCUP, HiTList, HiReport, HiOps, HiPPHOP, HiCat, HiDog, HiJack, … ). I have spent most of my time interacting with the HiRISE Targeting Specialists, or HiTS, the folks who do the day-to-day commanding of the individual images that HiRISE acquires.  I send them notes from the daily gamut of meetings I attend on their behalf, answer questions from them about what’s going on at JPL, and alert them to “shenanigans” (my preferred term for unusual events) in upcoming planning cycles.

The HiRISE science team gets together twice a year, and once a year they go on field trips through areas that include geological features that are analogs to places on Mars. In the course of attending these, I’ve travelled through areas once covered by giant volcanic flows and then cut by giant floods, pushed dry ice down sand dunes, and spent my 35th birthday standing barefoot on a beach made of preserved brine shrimp poo.

I’ve done two NASA press conferences for the HiRISE team.

I’ve helped the team as they figured out how to take pictures of comets, starting with last year’s ISON images, which at the time seemed mind-meltingly complicated, as we tried to understand how to take a camera designed to run hot and take pictures of a warm object that fills the entire field of view, and flip it over to take pictures of a tiny, faint object in a cold sky. I’ve been told that interpretive dancing was involved at HiROC (the HiRISE Operations Center) to figure out what was pointing where and where the sun was.  As complicated as that was, it seems so straightforward now that we’ve done the Siding Spring campaign!

There’s a lot of things out there now about the Comet Siding Spring campaign, including a video about how MRO and the other Mars orbiting fleet hid behind the planet during peak flux, and a NASAsocial about our plans, which can be watched here (I’m briefly in it about 55 min in).  But let me tell you, none of that indicates the level of sweat and tears and sheer determination behind the scenes. From the flight engineering team at Lockheed Martin, who figured out how to make the spacecraft do multiple flips every four hours starting 60 hours before closest approach and dealt with ever-shifting instrument desires, to the HiRISE and CRISM teams who figured out how to get their instruments to work in a way wholly incompatible with their design, to the team at JPL who combined our earliest observations with the ground-based comet observations to give us last-minute updates to the predictions of where the comet would be at closest approach (and saved the closest approach images), to the project management who made sure that everyone was dotting their i’s and crossing their t’s – how much did the comet move through the sky between the start of a HiRISE scan and the end of it? Was the spacecraft tracking the comet or pointing at a fixed spot? Were we going to fill up the data storage and start overwriting data before we could downlink it?  These images represent a huge amount of work, and I think they are spectacular.  More results should be coming from the team in the coming weeks and months.


More here.

Today is my final day as the HiRISE investigation scientist.

I’m now full-time as the Science Systems Engineer for the Mars 2020 Rover.  It’s my first mission in development, and it’s my first time having this level of responsibility. I’m looking forward to putting the things I have learned as a member of the operations teams for a diverse set of spacecraft to use as we figure out how we’re going to operate our new martian beast. It’s an amazing growth experience for me, and will put my skill set to good use (and stretch me to learn a whole new set of skills). But I’m sad to be leaving the team of the most awesome camera in the entire solar system, and I wish them every success.

What is a scientist doing on a mission that does not yet have a science team?

When I tell my scientist friends that I work part-time on the Mars 2020 Rover, I usually get confused looks: “But there’s no science team yet, what can you possibly be doing?”  Well, quite a lot actually!


I officially joined the 2020 mission operations team last fall as a science systems engineer.  A science systems engineer is someone who is focused on how all of the rover systems (from the components of the physical rover to the flight software that runs the rover to the ground network that we will use to build the commands during rover operations and process the data that the rover collects) will come together to support the science team.  We want to make sure that the people who are funding the rover – that means you, if you are an American – get the most scientific bang for their engineering buck. 


For the last 9 months or so, M2020 has been in what we call “Phase A” of project design – we are working out exactly what the rover is going to need to do (these are called requirements), paths forward for developing those capabilities, and thinking about how to test and verify that it can do those things before it launches. We are waiting for our science instruments to be selected by NASA HQ from the 58 proposals submitted from the Mars science community; however, even though we don’t exactly know which science instruments we will be carrying, we know the science goals of the rover.  We have a Project Scientist (Caltech professor Ken Farley), who is ultimately responsible to NASA HQ for the science achieved by the rover, but he can’t be everywhere all the time and he doesn’t have the familiarity with the engineering side of a spacecraft – so he has two science systems engineers to help make sure that the rover system will allow him and his team meet the science goals.


A major difference in science goals between M2020 and previous rovers is the development of a “returnable cache”. This means that M2020 must collect rock samples and put them in a cache, which a future mission could return to Earth should it be funded. The word “returnable” implies requirements for engineering (HOW to fill the cache?), planetary protection (how CLEAN is the cache?), and science (WHAT goes in the cache?). This latter component has a lot of implications that could easily be overlooked by the engineers focused on designing the hardware. One of the ways we tried to convey this message to the engineering team was to take some of them out into the field, and show them how a geologist would work to understand the history encoded in the landscape, and what samples would we choose to collect for further analysis. This was a lot of fun, but I’m going to save those stories for now – we’re hoping to put them up on the public M2020 website in the future. 


Another way to make sure that engineering decisions – even in this early stage of project development – are made with full recognition of the science implications of those decisions is to have a science representative in their meetings. That’s where I come in! One of the many meetings I’ve been attending is the cache hardware design team meetings so that I understand their trade spaces and to make sure they understand our science requirements, attending rover operability working group meetings to discuss how everything from the size of the heaters on the rover to the time that our relay orbiter flies overhead affects how much science we can do in a single Mars year, and where can we make reasonable changes to increase our science return. My job is to jump up occasionally to remind the engineers that we will want to collect soft rocks too (a whole different kind of drilling challenge), or that we need to take all the proper fieldwork-type measurements of the area to understand how the samples relate to the geology of area they were collected from, so we can’t just assume we will spend all of our time drilling or driving. 


It’s a lot of meetings, and a lot of discussing currently-nebulous design options or philosophical approaches to answering questions. It’s been a huge education for me in terms of developing a spacecraft, and how interconnected all aspects of a spacecraft are. It’s also been a time of emotional strain and growth for me, as sometimes I’ve had to speak up and argue against experienced engineers and managers, all of whom are very confident and not shy to share their opinions. I, on the other hand, am new to mission development, and if left to my own devices can be quite shy and introverted. I had to reconcile the fact that my area of scientific expertise is not astrobiology with the fact that I know more about astrobiology and the science goals of this mission than any of the engineers or managers. I went through a period of scrambling to find my confidence and my voice, but as I’ve gotten to know the team better and settle in to my new role, I have become more than willing to speak up and be an agitator on behalf of the future science team.


While it has been fun helping lay the groundwork for the rover, I’m looking forward to when some of these conversations become more concrete. All of us on the M2020 team – and in the Mars scientific community – are eagerly awaiting instrument selection.  Soon, I hope!

Thoughts on a Science Definition Team

There is a room at JPL that is currently covered in printouts – covering the walls and taped to the windows, stacked on the conference table, and in a few cases accidentally fallen on the floor. Each of these hundreds of pieces of paper is an individual step of logic in the chain that will hopefully take us to another great Martian adventure. This room is called the Mars 2020 War Room.

I’ve been noticeably absent from a number of things – as my MRO coworkers, my friends, and my husband can attest – for the last 6 months. That is because I’ve been working as support staff for the Mars 2020 Science Definition Team, and spending a lot of time in that room. (And yes, my boss has been known to quote Dr. Strangelove: “Gentlemen, there is no fighting in the War Room!”)

NASA spacecraft missions come in many sizes and flavors. Some are proposed by the scientific community in response to announcements of opportunity (these include the Discovery missions like MESSENGER and the New Frontiers missions like New Horizons). Some are pre-chosen by NASA to have a particular destination (these include flagship missions such as Cassini), and the scientific community proposes instruments to go on these spacecraft in order to carry out the measurements needed to answer the science questions that this spacecraft is intended to address. Before those instruments can be identified, a team of scientists is assembled to figure out what those science questions should be and what kinds of measurements are needed to address those questions. This is a science definition team.

Back in December of 2012, the associate administrator for NASA’s Science Mission Directorate (the part of NASA that includes all robotic solar system exploration) announced a plan to essentially rebuild and refly the Curiosity rover system in 2020 with new scientific instruments to answer new questions. NASA set forth an initial set of questions; a science definition team was put together to figure out if those were the right questions and how would we put together a realistic mission to answer them. Realistic is important: this encompasses if there are instruments in existence that can make the measurements, are those types of instruments affordable, and can we collect enough data in one Mars year of operations to answer the questions.

The Mars 2020 Science Definition Team (SDT) got started at the end of January, and turned in their report is to NASA on July 1. On July 9th, the report was released to the public; you can read it here ( and watch a video about the science goals here ( The punchline is that we want to look for the signs of past life on Mars via a suite of instruments onboard the rover combined with collecting rocks to eventually bring back to Earth to analyze for signs of life using terrestrial laboratories. This is very exciting to a Mars scientist – we’ve been trying to do Mars Sample Return for decades, and NASA has always been reluctant to take the first concrete steps before now. I’m not going to go into details of what we want to do right now, as I hope there will be plenty of time for that in the future; check out the video to find out more. Or, you can read our report!

The report is where I come in. I am the SDT Documentarian, which basically means that I am the keeper of the documents – multiple team-internal powerpoint files (each of more than 100 slides) and the final report (just over 200 pages). I wrangled figures, files, meeting notes, and text so that the SDT didn’t have to, and I made sure that their thoughts are captured electronically so that the science content and logic is there but in a way that a non-expert can understand it. (To be clear: all the intellectual content was generated by the people on the SDT and not myself.) It’s the sort of task that requires someone with a scientific background (in order to understand the conversation and make sure the important parts are captured) but who is willing to be a beast of burden (in order to pull together the inputs, edits, and quibbles of ~20 very smart people). I helped to keep the train running so that the SDT could decide where it is going. I work for two people here at JPL who have been stoking the fires and making sure that track exists, and I run around doing what I can for them so that they are free to keep their eye on the horizon.

It’s been fun and intense. I’ve spent a lot of late evenings gathering up and reconciling inputs, and turning around a new product to the SDT so that it is sitting in their inbox for them to start working on afresh as soon as they get in the office in the mornings. I’ve worked with some of the team before on other missions, including Curiosity and Mars Phoenix. One was a researcher in my department at grad school and another served on my Ph.D. thesis committee. I’ve been struck by their dedication: unlike myself, they are volunteers and not getting paid for this work, and they have put in a lot of time into nailing down the precise wording of their findings and arguing their way through the logic of each step in the chain, simultaneously with teaching, participating in MER and MSL operations, and doing their own research.

It was strange to have this document lurking on my computer and be so very excited about its findings but not actually be able to tell anyone about them. Although I was on vacation this past week, I went in to work to watch the press conference and I spent several hours watching what people were saying on twitter. I eventually had to pry myself away and get back to my vacation (with some reminders from my twitter friends! HiCommander, I’m looking at you.)

If all goes well, later this year NASA will release an announcement of opportunity to the community and people will be able to propose instruments to go on the rover. I think this would be a very exciting mission, and I hope that the rest of the planetary community and NASA agrees with me. Even at this stage, this is still just a proposed mission, and I’m not sure what role if any I will be playing in its future, but I hope it will take us all the way to the surface of Mars – and maybe even return some of Mars back here to Earth.

You can keep an eye on our progress at the official Mars 2020 website,