Astronomy 18 oz Steel Bottle
Fill this flask with some piping hot mulled cider, grab a blanket and your telescope, and alight for an evening of stargazing. Sit down to a morning astronomy lecture or let this flask inspire you to keep seeking answers to matters of spacetime.
With a textured design for a unique tactile experience, this flask will keep your drink hot or cold until you're ready to enjoy it.




Here's how it works: the space between the inner and outer flask wall is evacuated, creating a vacuum (well, a partial vacuum anyway...). In order for heat transfer to take place from the outside world into your cold drink, or from your hot drink to the outside world, it needs nearby molecules to excite. If there aren't many molecules nearby, as is the case in a vacuum, the heat's energy can't easily be passed along, so your drink stays close to the temperature it was when you put it into the flask for a really long time.
Simply stated, vacuums make great thermal insulation!
Volume | 18 oz | 530 mL |
Width | 2.75" |
Height | 8.75" |
Opening | Wide mouth |
Material | High-grade stainless steel |
Origin | Designed in Oregon, Built responsibly overseas |
Cap Material | High-grade stainless steel, silicone ring |
Care | Hand wash only |
••• Holiday 2023 Shipping Dates & Deadlines •••
USA
Flat Rate $7.95
Orders $40+ ship for free
Expedited service available
International
Shipping is available to most countries. See details at checkout.
If you're shipping to Europe, Asia, the Middle East, or Oceania, please check out our European website for lower shipping rates and quicker delivery times.
Frequently Asked Questions
Peer Reviews
- Reviews
- Questions

Unique
I depend on Cognitive Surplus for unique gifts, and the are yet to disappoint! This gift was a perfect fit for the my nerdy recipient! The customer service at Cognitive Surplus is amazing. I made a mistake with my order and they immediately fix it. I am grateful!

Awesome flask
I received one of these drinkbottles as a gift and I am obsessed with everything from the design to the texture. The bottle is sturdy and I love the convenience of the handle :)


Beautiful flask
I bought this as a Christmas present for my boyfriend, and he's absolutely loved it! The design is gorgeous, and the flask is well built and sturdy.
Astronomy Stainless Steel Vacuum Flask
very nice material, works very well

Great product
Bought this flask for an Easter present for my son. Ice doesn’t melt quickly so water stays cold; perfect for taking to class or for a workout.
Astronomy Stainless Steel Vacuum Flask
My sister liked hers so much, I decided to get my own. It's lovely as usual, and functional!

Cool Flask
My girlfriend loved it. Keeps temperature for a super long time and has a pleasing texture.