How radio astronomy uncovers our hidden universe
Radio astronomy is the practice of studying the natural radio waves that come from objects in our universe, like planets, stars and even galaxies. By using this form of astronomy, scientists can study faraway objects and make new discoveries -- like finding exoplanets.
The naked eye cannot see these waves. According to the National Radio Astronomy Observatory, radio signals and data can then be turned into images “that are colored in different ways to show characteristics of the object such as its temperature, ‘clumpiness’, or the strength of radio emissions from different regions. The resulting images let scientists and the public see the otherwise invisible radio objects.”
Emma Chapman, an astrophysicist and the author of the new book, The Echoing Universe: How Radio Astronomy Helps Us See the Invisible Cosmos, said this from of astronomy can be defined in simple terms: It’s just “communicating with the universe, that's it, that's your simple answer.”
Chapman explained that there are two components of radio astronomy, listening for radio waves and sending out radio waves.
Chapman said the active part of radio astronomy is “when we can actually send out radio waves, bounce them off stuff, whether it's asteroids or the surface of Venus or Mercury, and then they echo back. They return back to us, this radar, and then we can work out from how long those waves have been away.”
Unlike other forms of astronomy, Chapman explained that radio astronomy is very active. Plus, using this form of astronomy allows scientists to get information back very quickly in minutes, or even seconds.
“So much of astronomy is sitting there and waiting and hoping the thing that you want to explode explodes,” Chapman said. “Whereas with radio astronomy, you can just kick those radio waves out and be like ‘I'm going to see what Venus is up to today,' boing, and I can just have some fun with it.”
Fueling space explorers with good food
A lot goes into the meal planning and the selection process for astronauts’ diets. Food for space missions is carefully selected for each mission, with attention to both nutrition and preference.
We spoke with Ryan Dowdy last week on “Are We There Yet” about space food. Dowdy is a NASA scientist and founder and CEO at READYBAR. From 2014 to 2021, he managed the food that was sent to the International Space Station.
One food Dowdy presented to the astronauts was jalapeno walnut bars, something he thought the astronauts would enjoy. But when they did not enjoy it, Dowdy realized that most space travelers want meals that remind them of home, not new food.
“Astronauts are doing 50 different science experiments a day that they've never tried before, and they got to have an EVA (Extravehicular Activity) the next day that they're prepping for, and so food needs to be a psychological comfort, as opposed to a psychological stretch,” Dowdy said. “So that that comfort aspect was funny.”
After every mission, Dowdy took time to meet with the astronauts to talk about the food they ate while in space. Dowdy said astronauts enjoy a wide variety of condiments, because the space environment changes the way people can taste and smell.
“There's a fluid shift, the fluid that's normally being pulled down towards your feet by gravity is now up in your head, and it fills up your sinus cavities,” Dowdy said. “You can't smell, and 70% of the flavor of food actually comes from your nose…so that's why horseradish, hot sauce, and pepper…so that absolutely played into how we design foods. Artemis II took five different hot sauces with them, and its hot sauce is a huge part of space food culture. “
Out of all the food Dowdy helped send on different missions, he said his favorite addition was plain black coffee. He said it took some convincing, since people were worried that some people would take coffee with cream and sugar, but the data showed the opposite.
“We looked at the data over the last 20 years of consumption on the ISS, and do you know what the single drink is that every single astronaut consumes? Black coffee…I was so happy because once we added that to the menu, it actually helped kick the astronauts into even higher gear. Because they're high performers – they run marathons in space for crying out loud – so they love their caffeine.”
