Why Can You Sometimes See Your Breath?

Chalabala/iStock via Getty Images
Chalabala/iStock via Getty Images

The human body is made up of about 60 percent water, meaning that when we breathe, we don’t just exhale carbon dioxide—we also exhale a certain amount of water vapor.

Water molecules need a lot of energy in order to remain in a gaseous form. When the warm water vapor molecules from your lungs reach colder air, they condense into “tiny droplets of liquid water and ice,” according to Wonderopolis. In fact, this process of condensation is also how clouds are formed.

But it’s actually relative humidity, not just temperature, that determines whether you can see your breath. The water vapor in your breath condenses into a liquid when it hits dew point—the temperature at which the air is saturated and can’t hold any more water in gas form. Since cold air can’t hold as much water vapor as warm air, you're much more likely to see your breath on a chilly day, but that's not always the case.

On more humid days, you may be able to see your breath even when it’s relatively warm outside. That’s because the air is already more saturated, making the dew point higher. And on especially dry days, even if it's cold outside, you may not be able to see your breath at all. Dry, unsaturated air can hold more water vapor, so you can huff and puff without seeing any evidence of it at all.

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Kodak’s New Cameras Don't Just Take Photos—They Also Print Them

Your Instagram account wishes it had this clout.
Your Instagram account wishes it had this clout.
Kodak

Snapping a photo and immediately sharing it on social media is definitely convenient, but there’s still something so satisfying about having the printed photo—like you’re actually holding the memory in your hands. Kodak’s new STEP cameras now offer the best of both worlds.

As its name implies, the Kodak STEP Instant Print Digital Camera, available for $70 on Amazon, lets you take a picture and print it out on that very same device. Not only do you get to skip the irksome process of uploading photos to your computer and printing them on your bulky, non-portable printer (or worse yet, having to wait for your local pharmacy to print them for you), but you never need to bother with ink cartridges or toner, either. The Kodak STEP comes with special 2-inch-by-3-inch printing paper inlaid with color crystals that bring your image to life. There’s also an adhesive layer on the back, so you can easily stick your photos to laptop covers, scrapbooks, or whatever else could use a little adornment.

There's a 10-second self-timer, so you don't have to ask strangers to take your group photos.Kodak

For those of you who want to give your photos some added flair, you might like the Kodak STEP Touch, available for $130 from Amazon. It’s similar to the regular Kodak STEP, but the LCD touch screen allows you to edit your photos before you print them; you can also shoot short videos and even share your content straight to social media.

If you want to print photos from your smartphone gallery, there's the Kodak STEP Instant Mobile Photo Printer. This portable $80 printer connects to any iOS or Android device with Bluetooth capabilities and can print whatever photos you send to it.

The Kodak STEP Instant Mobile Photo Printer connects to an app that allows you to add filters and other effects to your photos. Kodak

All three Kodak STEP devices come with some of that magical printer paper, but you can order additional refills, too—a 20-sheet set costs $8 on Amazon.

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What Is the Citizenship of a Baby Born on an International Flight?

Nadezhda1906/iStock via Getty Images
Nadezhda1906/iStock via Getty Images

It's pretty standard medical advice: a pregnant woman shouldn’t travel via airplane 36 weeks or later into her pregnancy. Despite that precaution, an occasional bundle of joy may still add an unexpected passenger to the flight manifest. As if giving birth at 40,000 feet wasn't already a stressful experience for a new mom, things can get even more hectic upon landing: Depending on the details surrounding the birth, her newborn’s citizenship could be up for debate.

There is no universal rule for how a country determines the citizenship of a newborn. Some countries just follow the jus sanguinis (right of blood) law, which means a baby’s nationality is determined by that of one or both parents. Others observe that rule and jus soli (right of the soil), where a country grants citizenship to a baby that’s simply born on its soil, regardless of the parents’ origin. These countries are mostly in the Americas and include the United States and Canada. And with the expansion of air travel, these laws had to extend to the heavens as well.

If a baby is born over United States airspace, the jus soli rule means the child would be granted U.S. citizenship, according to the Department of State Foreign Affairs Manual. Depending on the circumstances, the child may also be a candidate for dual citizenship if its parents are from a country that grants citizenship based on blood—though that would depend on the countries involved.

This same simplicity doesn’t extend to a jus sanguinis country, though. This means that an American mother can’t attain French citizenship for her baby just because she gave birth over French airspace. The baby would simply revert to the parent's U.S. citizenship, since the United States also generally follows jus sanguinis when a baby is born to U.S. citizens in a foreign country. Since jus sanguinis is the far more common rule around the globe, most babies born on a flight over international waters or foreign airspace will likely wind up taking the citizenship of its parents.

If there’s a case where the child could potentially be stateless—such as when a mother herself has no official citizenship and the baby is born in international airspace—the baby would likely take the citizenship of whatever country the plane itself is registered in, according to the United Nations’s Convention on the Reduction of Statelessness agreement.

Despite all these complex laws, mid-flight births are exceedingly rare—so rare, in fact, that most airlines don’t even keep track of the number of babies born in the air. An expecting mother likely wouldn't even be able to get onto a flight in the first place, since many airlines have rules that prohibit women from flying after they've reached a certain point in their pregnancy.

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