Scott Simon is the host.

I'm pretty sure no one else thought to ask, at least in this way, why the rest of the universe exists.

There is an interview with NPRBROADCAST.

There are theories that the explanation may be hidden in the electric dipole moment. It isn't a moment as in a moment. The neutron is a bit more football shaped than spherical.

Joe Palca, our colleague, was the one who said that. He made an art form out of explaining the difficult things. Joe has covered science for NPR for 30 years.

It's not so, Joe.

I decided that can't really. I wonder why I am leaving. It just seemed like it was time. It's better to leave when people want you to stay.

SIMON: Well, that's right.

Wait until the other proves to be the case.

It's better to jump than be pushed.

Something like that is what Paco said.

SIMON: Yeah, that's right. We have a lot to ask you on your way out of the building. Over the years, you've been our guide. What made you want to report science?

The interesting part to me is the question you posed about the electric dipole moment. The electric dipole moment is what it is.

Excuse me, did you ask that question?

It's right, Paco.

I simply said it. I had never heard of it. Yes.

Exactly, that's right. You are absolutely correct. I didn't hear of it as well. I had no idea what it meant. A lot of people were searching for it. There is something magical about searching for something that is obscure but potentially important. A lot of people thought this was a story about sandwiches, but when they learned about the electric dipole moment of the neutron, they were disappointed. If people are able to see that beauty or help them see it, that's great.

The Mars rover landings were covered by Joe.

When I was sent to Mars in 1997 for the first time, it was a little more like "let's go down to the barn and build a spaceship kind of thing." Compared to other NASA missions, it was a little more like "Let's go down to the barn and It didn't have a lot of people to work with. There was a small group of people. That mission was a success.

David Kestenbaum was sent to Mars the next time there was a landing. Let's go back to Palca. They all succeeded after I did the next four in a row. I've covered all the successful Mars landings since 1997 and the one that failed was the one that David Kestenbaum was assigned to. NASA is worried that I'm leaving.

It's true, SIMON. With good reason.

It's true, Paco.

There's a clip from your piece about the second Mars rover landing.

There is an interview with NPRBROADCAST.

Rob Manning is five minutes and 55 seconds after entering. We should be moving around.

Bouncing on the ground is protected by an air bag. The rover wouldn't bounce as much if the air bag hadn't inflated. They inflated.

The man is getting a bounce.

There are people who say yes.

There is a bounce signal.

The hair is still on the back of my neck when I hear that. I get to know him and he is excited. It is powerful.

What is it like to cover a historical event?

You want to be transparent. Some people told Joe that he was getting too excited. You are making it sound like you are cheering. I am not being a cheerleader. I'm talking about something. The thing was amazing. Should we have spent the money or did we get enough out of it? That's okay. It was amazing at that time.

There is a tragic moment I think both of us remember. The space shuttle fell apart as it reentered the atmosphere. Both of us were in the studio that day.

Paco remembers it very well. She called my house after nine.

Gwen was our editor at the time.

That's correct. She said that the shuttle is late. It was my first thought that delayed is not good. I jumped in my car and went to the studio to find out what was happening. I knew about the program but I didn't know a lot about the mission.

It's true. What stood out to you that you were able to pass on to others?

There is another one that you may not have heard of. It's a biological technique for changing genes or removing genes. I didn't know what it was when I read about it. I know what it does but I can't say how it works. The woman who did it told me that she was going to win the prize. She was the winner of the prize.

A high point for WEEKEND EDITION is when you made a pickle glow. Are you aware of that?

It's true, Paco. Someone asked Joe if he could come up with a demo for the live show that was cool looking.

We do a show before an audience.

It's true, Paco. Sorry, well. That is what I said. We did this in person. I think we tried it. It may have been a failure, but it was not.

There is an interview with NPRBROADCAST.

Plug it in and see what happens. There is a little bit of smoke coming out of the end, but you can see it.

Joe, it's a pickles. I do not.

Just wait a second.

Wait, oh, wait. Some smoke is visible.

You can see some smoke.

Smoke comes out of the end. I think it looks like that.

There is aCHEERING.

There is a fire. The pickles are glowing.

Wow! I sound excited as if I'm about to land on the moon.

Some people like glowing pickles. I can't say anything. It was a pleasure. It's kind of silly. It wasn't the most serious piece I've ever done, but it was enjoyable. It had a little of science.

You touch on something that has really changed your work. It doesn't have to be obvious to apply. It's wonderful to know and to watch science.

It's true, Paco. There was a famous question about the Fermilab that was asked in congress. The senator wanted to know how this would help the defense of America. The scientist says it isn't. He said not at all. It will make America more worth defending.

It's part of our culture to explore the outdoors. It improves us for it. Some things we'll learn, and they may be stuck on a shelf and never become relevant, and some things that will change the way we think of ourselves.

It's true. Thank you, Joe, for everything you've done for us over the past three decades. It is a sad honor for me to say goodbye to Joe. Thank you a lot.

It has been my pleasure.

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