Lots of plants are smooth to the touch, and some are even soft and feathery like flowers! So why are cactuses prickly and sometimes even painful? We asked botanist Rachel Jabaily from Colorado College to answer this spine-tingling question. 


Got a question that’s prickling at your brain? Send it to us at BrainsOn.org/contact, and we’ll help sharpen you up.

Lots of plants are smooth to the touch, and some are even soft and feathery like flowers! So why are cactuses prickly and sometimes even painful? We asked botanist Rachel Jabaily from Colorado College to answer this spine-tingling question.  Got a question that’s prickling at your brain? Send it to us at <a href="http://brainson.org/contact">BrainsOn.org/contact</a>, and we’ll help sharpen you up.

Moment of Um is your daily answer to those questions that pop up out of nowhere and make you go… ummmmmmm. Brought to you by your friends at Brains On Universe.

Sales and Distribution by Lemonada Media https://lemonadamedia.com/  

Moment of Um is your daily answer to those questions that pop up out of nowhere and make you go&hellip; ummmmmmm. Brought to you by your friends at Brains On Universe.
Sales and Distribution by Lemonada Media <a href="https://lemonadamedia.com/" data-stringify-link="https://lemonadamedia.com/" data-sk="tooltip_parent">https://lemonadamedia.com/</a>&nbsp;&nbsp;

Moment Of Um

Why are cactuses prickly?

We’re back! We’ve officially moved into our new headquarters! Come unpack with us and get a tour while we fill you in on some big news. Plus, new episodes of Brains On coming later this month and new Smash Boom and Forever Ago after that. If you want to support the show or drop us a line, head to brainson.org. The best way to keep us going is to join Smarty Pass or donate here:https://brainson.supercast.com. Thank you!


See Smash Boom Best LIVE in Princeton, NJ!


Join us at the McCarter Theatre for a live, in-person version of Smash Boom Best, an award winning podcast for kids and families! Each live show takes two cool things, smashes them together and lets the audience decide which is best. Host Molly Bloom moderates a debate between two performers who make their case using facts fueled by jokes, physical comedy, and the occasional song and dance. At the end, the audience votes for the winner and crowns the Smash Boom Best – all while learning how to defend their own opinions and make the strongest arguments for their case. 


While we are in town, we are throwing a Smash Boom Spectacular Party right after the live show and YOU are invited! This won't be just any party. You will get to meet host Molly Bloom and our debaters. They'll be playing games with you, singing songs, answering your questions, and posing for photos. Plus, you'll get to take home an awesome, one-of-a kind Smash Boom Best goodie bag. You can gain access to this SBSP (Smash Boom Spectacular Party) by purchasing a VIP ticket* when you make your purchase.  See you there!





DETAILS & TICKETS


McCarter Theatre Center


October 26, 2025 at 3:00pm ET


91 University Place


Princeton, NJ 08540


Buy Tickets Here

We’re back! We’ve officially moved into our new headquarters! Come unpack with us and get a tour while we fill you in on some big news. Plus, new episodes of Brains On coming later this month and new Smash Boom and Forever Ago after that. If you want to support the show or drop us a line, head to <a href="https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fbrainson.org%2F&amp;data=05%7C02%7Clhumpert%40americanpublicmedia.org%7Cc8916b86364f492e178908de05f27929%7C8245ecb6b08841218e216c093b6d9d22%7C0%7C0%7C638954736152126086%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&amp;sdata=QoP0jxHXjCVYrfvIz4%2FXZM8wy%2FnHFBTo51NJtOQuRXU%3D&amp;reserved=0" class="OWAAutoLink">brainson.org</a>. The best way to keep us going is to join Smarty Pass or donate here:<a href="https://nam02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fbrainson.supercast.com%2F&amp;data=05%7C02%7Clhumpert%40americanpublicmedia.org%7Cc8916b86364f492e178908de05f27929%7C8245ecb6b08841218e216c093b6d9d22%7C0%7C0%7C638954736152154857%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&amp;sdata=P%2FPxx1mVHb3nQmMONLqCL%2FKHhUeT0vt2TrScdc4lYq4%3D&amp;reserved=0" class="OWAAutoLink"> </a><a href="https://nam02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fbrainson.supercast.com%2F&amp;data=05%7C02%7Clhumpert%40americanpublicmedia.org%7Cc8916b86364f492e178908de05f27929%7C8245ecb6b08841218e216c093b6d9d22%7C0%7C0%7C638954736152179300%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&amp;sdata=xC4%2BfJUg5xUvo4SxQkTHogdS7npwBIJd02Eh%2FLeSpEI%3D&amp;reserved=0" class="OWAAutoLink">https://brainson.supercast.com</a>. Thank you! See Smash Boom Best LIVE in Princeton, NJ! Join us at the McCarter Theatre for a live, in-person version of Smash Boom Best, an award winning podcast for kids and families! Each live show takes two cool things, smashes them together and lets the audience decide which is best. Host Molly Bloom moderates a debate between two performers who make their case using facts fueled by jokes, physical comedy, and the occasional song and dance. At the end, the audience votes for the winner and crowns the Smash Boom Best – all while learning how to defend their own opinions and make the strongest arguments for their case.  While we are in town, we are throwing a Smash Boom Spectacular Party right after the live show and YOU are invited! This won't be just any party. You will get to meet host Molly Bloom and our debaters. They'll be playing games with you, singing songs, answering your questions, and posing for photos. Plus, you'll get to take home an awesome, one-of-a kind Smash Boom Best goodie bag. You can gain access to this SBSP (Smash Boom Spectacular Party) by purchasing a VIP ticket* when you make your purchase.  See you there! DETAILS &amp; TICKETS McCarter Theatre Center October 26, 2025 at 3:00pm ET 91 University Place Princeton, NJ 08540 <a href="https://www.mccarter.org/smashboombest" title="Buy Tickets Here" class="default">Buy Tickets Here</a>

We’re back! Brains On Universe has a new headquarters

We're moving the Brains On Universe Headquarters, and that means we have to stop putting out new episodes until we get settled. We know: not cool. But, our new home is going to be bigger and better and the absolute BEST. We can't wait until it's ready for you to visit.


In the meantime, we still have some live shows planned this fall. Brains On Live will be in Dallas, TX on September 13. And Smash Boom Best will bring the debate heat to Princeton, NJ on October 26. Head over to brainson.org/events to get tickets. We can't wait to high five you all in person!


And, if you want to be the first to hear about our shiny, new home, sign up for our newsletter. There will be six more bathrooms, 10 more water slides and, we're finally going to fix the doorbell! Also, if you have any questions or want to reach out to us, you can still head to brainson.org/contact to get in touch.

We're moving the Brains On Universe Headquarters, and that means we have to stop putting out new episodes until we get settled. We know: not cool. But, our new home is going to be bigger and better and the absolute BEST. We can't wait until it's ready for you to visit. In the meantime, we still have some live shows planned this fall. Brains On Live will be in Dallas, TX on September 13. And Smash Boom Best will bring the debate heat to Princeton, NJ on October 26. Head over to <a href="https://www.brainson.org/events" class="default">brainson.org/events</a> to get tickets. We can't wait to high five you all in person! And, if you want to be the first to hear about our shiny, new home, <a href="https://www.brainson.org/newsletter" class="c-link c-link--underline">sign up for our newsletter</a>. There will be six more bathrooms, 10 more water slides and, we're finally going to fix the doorbell! Also, if you have any questions or want to reach out to us, you can still head to <a href="http://brainson.org/contact" class="c-link c-link--underline">brainson.org/contact</a> to get in touch.

A big update about Moment of Um and the Brains On Universe

They come in cool colors, catch popcorn kernels and sometimes even have spacers - it’s braces! Ever wondered how braces magically straighten teeth? We asked Dr. ArNelle Wright - a real life dentist! - to help us break down the science of these tiny metal wonders.


Bracing for a tough question? Send it to us at BrainsOn.org/contact, and we’ll help uncover the tooth. 

They come in cool colors, catch popcorn kernels and sometimes even have spacers - it’s braces! Ever wondered how braces magically straighten teeth? We asked Dr. ArNelle Wright - a real life dentist! - to help us break down the science of these tiny metal wonders. Bracing for a tough question? Send it to us at <a href="https://www.brainson.org/contact">BrainsOn.org/contact</a>, and we’ll help uncover the tooth.

Why are cactuses prickly?

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