I am Lisa Grossman, space writer for Science News. NASA's Opportunity rover's Mars mission (which I briefly worked on) is officially done. AMA!

My daughter wants to be a science related field, she is six and society pushes Disney Princesses and barbies at her but she loves microscopes, geology and telescopes. What advice could you give her about being in your field? I would love her to hear from a successful and intelligent woman.

Oh wow I love this question! My advice is to stay curious, work really hard and never let anyone tell you you're not good enough because you're a girl. Girls are every bit as good at science and math as boys are. If anyone tries to tell you otherwise, ignore them, because they're wrong. Ask lots of questions and have lots of fun.

Also, it's totally okay to like Disney Princesses AND telescopes! I do. :)

Oppy lasted more than 50 times its design life. Spirit lasted many times its design life as well. Why were the estimated design lives so short, and why did mission planners not count on more time initially? What does the massive success and longevity of this program mean for future Mars/space technology?

The team estimated that dust collecting on the rovers' solar panels would shut down their ability to charge after about 90 Martian days (or sols). But it turned out that natural wind storms cleaned off the solar panels every winter, allowing the rovers to keep going. No other rover or lander had spent so much time on Mars before, so the team didn't know to plan for that.

The next two NASA Mars rovers (Curiosity, which landed in 2012 and is still going, and Mars 2020, which launches next year) use nuclear batteries, so they're not as concerned with dust. Curiosity got some amazing pictures of the rusty sky during the global dust storm last year. The next European Mars rover, which was just named Rosalind Franklin, is solar powered, so they'll use what Spirit and Oppy learned to keep the batteries running.

I thought that nuclear reaction power was something we'd basically stopped doing because of, among other things, range safety implications during launches. Given the recent history of rocket launch failures, is this still on everyone's radar (so to speak)?

It's still used, but yeah, it's contentious! The Philae lander that was part of the Rosetta mission to a comet a few years ago didn't use nuclear power because of concerns about launch failures. The lander crashed and bounced and ended up with its solar panels facing in a bad direction, so it couldn't charge. I've heard some people speculate that if it had been able to use nuclear batteries, it would've survived.

RIP Opportunity. Felt a little sad. Did you cry yesterday?

I did tear up a little in the press conference today, when principal investigator Steve Squyres opened his remarks by saying hi to all his friends and saying "I love you guys. It's just great to see everybody." <3

Is there a chance it could turn itself on again one day? And would that make it a zombie robot?

The chances are preeeetty slim. If the solar panels were cleared of dust and the battery was able to charge again, then maybe. But the team thinks the rover powered down to the point where its internal clock got out of sync with the real Martian day/night cycle. Opportunity has had an issue since the very beginning of the mission where where one of its arm heaters is stuck on. So if it's not going into a power-saving deep sleep mode at night, that arm heater drains the batteries all the way down before it has a chance to call Earth. So things look tough.

Hi Lisa! Will NASA check in with opportunity in the future just in case it ever comes back online?

I don't think so, not specifically. I think that's pretty much what today's announcement meant. But the Deep Space Network of radio telescopes listens to Mars all the time, because there are so many other spacecraft there. I think if Oppy suddenly started broadcasting again, they'd probably notice.

What (if any) schooling did you take to get where you are?

I took pretty much all the math and science classes offered at my high school, and I got a bachelor's degree in astronomy at Cornell. I did two summers of research in college, but I also wrote for my college newspaper. After college I did a one-year graduate course in science communication at UC Santa Cruz. I don't think any of those routes are the only way into a field like this, though! I know a lot of people who took totally different paths.

So given Opportunity had extended range. A few questions, given that the space hardware seems to last beyond its mission.

1. Does NASA plan auxiliary objectives beyond the primary mission knowing that they might get more time?

2. How do they come up with new and novel tasks for their robot on mars? What role does a news person have in contextualizing that in terms of science communication?

3. Who do you think your primary audiences is for this kind of work? The Layperson? Scientists? Space enthusiasts?

1. Missions usually have what's known as a "primary" mission, which meets the initial design goals and science objectives. After that's met, the team running the mission can appeal to NASA for "extended" missions. The proposals lay out new science objectives to get done in the extended timeframe. I don't even know how many extensions Opportunity had, but I know the team was writing the next proposal this winter, still hoping the rover might wake up.
2. The rover sees new things every day, so they mostly just follow what's interesting! I think my role is capturing that excitement and transmitting it as widely as I can, so people can follow along. And I think the Spirit and Opportunity teams were really good at outreach. They really cared about sharing what they were finding.
3. I think my audience is all three: anyone with an interest in space, whatever their background.

I keep hearing the "only expected to last 90 days" timeframe. Was that a minimum expectation for mission success, or did NASA consider that realistic? And was it dust damage, power limitations, or something else that worked better than expected?

That was a minimum; some of the team talk about it like that's when the warranty ran out. The team expected dust on the solar panels to build up too much for the rovers to function at the end of 90 (Mars) days, but seasonal winds kept blowing the dust off. It was pretty lucky! The batteries were also incredible - Opportunity's battery still had 80% functionality at the end of the mission. And the engineers kept figuring out clever ways to keep the rovers moving as they wore down. My favorite is when Spirit's front wheel got stuck, the team decided to just drive backwards and drag the broken wheel in the dirt. That made Spirit dig a little trough that exposed cool material beneath the surface.

Are aliens real? 🤭

Maybe! But we don't have any direct, unambiguous evidence for them (yet?).