4 things you should know about the science of smell, megaconstellations, and the future of fruit

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Meet Renée-Claude Goulet and Michelle Campbell Mekarski.

They are Ingenium’s science advisors, providing expert scientific advice on key subjects relating to the Canada Agriculture and Food Museum and the Canada Science and Technology Museum. Jesse Rogerson, formerly the science advisor for the Canada Aviation and Space Museum, continues to lend his expert voice to the Channel.

In this colourful monthly blog series, Ingenium’s past and present science advisors offer up three quirky nuggets related to their areas of expertise. For the July edition, they invited student intern Victoria Banderob to add her voice to the column. Collectively, they tackled the science behind stinky flowers and rain, astronomy amidst megaconstellations of satellites, and how bubble guns may help the future of fruit.

A tall corpse plant grows under a canopy of green plants in a greenhouse. The tall, thick, beige stem emerges from a massive fanned shell or petal. The shell is green from underneath, and dark maroon in the middle.

The green and maroon outer shell (spathe) hide the clusters of flowers found on the bottom of the stem that protrudes from the middle of the plant. 

Don’t judge a flower by its stench

Something rather fishy is happening in greenhouses across the world this summer. Plants that are taller and wider than most humans — and emit the pungent odour of rotting meat — are blooming.

The Amorphophallus titanum, or corpse flower, spends years building up its energy until it’s ready to undergo an intense, whirlwind flowering event. It blooms once every three to 10 years and has just 24 to 48 hours to attract its pollinators and reproduce.

The stem of the corpse flower produces chemicals that smell like rotting fish (trimethylamine) and sweaty socks (isovaleric acid), in the hopes of tricking beetles and flies into thinking it’s a decomposing animal. To improve its chances of attracting these pollinators, the stem generates heat — reaching up to 37° C. As the air around the stem warms up, the hot air rises and sends the putrid chemicals lofting into the air. 

The corpse flower also attracts humans — not for the smell, but for the once-in-a-lifetime chance to witness the majestic bloom tower over them. The plant originates in the rainforests of Sumatra, Indonesia, but are now found growing in greenhouses around the world for the public to see. With physical distancing rules in effect, greenhouses have adapted viewing experience so the public can follow the flowering event on social media and live streams from the safety (and smell) of their own homes. 

Recent blooms could be seen at Barnard College in New York and the Franklin Park Zoo in New England; however, there are no active blooms in Canada and it is nearly impossible to predict when another will take place. For now, you can watch time-lapse recordings of blooming events and enjoy the beauty…without the stench.

By Victoria Banderob

Living things in soil produce the “smell of rain”

There is a particular odour to rainfall on dry, parched ground. You must have smelled it before…that earthy scent that fills the air after the first drops of rain, or even as a storm is approaching. This scent actually has a name: petrichor. This term was coined in 1964 by mineral chemistry researchers studying its source.

In fact, the scent of petrichor comes from many different molecules released by soil microbes and plants! There are billions of living organisms in a single tablespoon of soil. Most of these are microscopic beings, including archaea (very ancient and bacteria-like), bacteria, fungi, and actinomycetes (bacteria that behave like fungi in many ways). These minuscule but abundant organisms are basically responsible for decomposition of dead plant and animal matter (including their wastes), releasing nutrients back into the soil for plant growth. 
Through their everyday activities, soil microbes also produce wastes, which can take many forms. Within the actinomycetes, there is a group that releases a chemical called geosmin — an important part of petrichor. Newer research suggests that these microbes release geosmin to attract springtails — tiny soil bugs that feed on the bacteria and help them spread. Geosmin, along with the plant oils also part of the scent of petrichor, accumulate in pores in the soil.

Human noses are very sensitive to geosmin, so there doesn’t need to be much of it in the air for us to notice it. Rain hitting the ground fills the pores and creates tiny droplets, which spray into the air, making the scent molecules airborne. It stops once the soil is wet. 

So the next time it rains, enjoy the petrichor, knowing that it’s a wonderful connection to the living world beneath our feet!

By Renée-Claude Goulet

An image of the night sky, with many individual stars visible. There are a large number of white streaks going across the image, created by the Starlink satellites flying through the frame.

In a long exposure, the light reflected by a satellite as it passes through the frame of the image is stretched into a bright streak, which negatively affects or ruins the image completely. 

Astronomy in an age of megaconstellations

Starlink is a planned megaconstellation of telecommunication satellites that is currently being deployed by SpaceX. The satellites will provide high-speed internet to all locations around Earth.

If you live in a populated area, high-speed internet is readily available through ground-based infrastructure (cable, phone lines, fibre optics, etc.). However, in remote areas, the internet is provided via satellite. For example, the Canadian company Telesat operates a fleet of 16 different telecommunication satellites at geostationary orbit (about 36,000 km altitude). In stark contrast to that, SpaceX’s Starlink megaconstellation, when completed, will be 12,000 satellites strong (and possibly as many as 42,000), and will operate at a much lower altitude of 550 km. The first batch of Starlink satellites was launched in February 2018. Now, after 10 launches, there are currently over 500 in operational orbit.

Due to both the extremely large number of satellites as well as their low orbital altitude, astronomers are worried there could be detrimental effects to their science. For example, the Cerro Tololo Inter-American Observatory in Chile snapped the accompanying five-minute long image that shows 19 streaks from the Starlink satellites already in orbit. A recent analysis of Starlink’s impact on observational astronomy indicates hundreds of Starlink satellites will be visible at once; they will be bright enough to be seen by the naked eye. The study concluded that while some science will not be affected, other types of observations — such as long-exposures with a wide field of view, or those at twilight — will be greatly impacted.

Moreover, the increase in launches and operational satellites will result in more space junk, an ongoing threat to space operations. Over 25,000 individual pieces of space debris are being tracked by the Canadian Space Operations Centre, NASA, and other administrations around the world.

Starlink is not going to be the only megaconstellation; there are other proposed projects from Google or Amazon already in development. The use of space to create worldwide access to reliable internet is important work, but working with scientists to help reduce negative impacts is vital.

By Jesse Rogerson

A soap bubble sits on the center stalk of a purple flower

Bubbles provide a gentle way to deposit pollen grains on delicate flowers.

Bubble guns and autonomous drones may boost the future of fruit

With pollinator populations in steep decline due to habitat loss, changing climate, pesticides, and disease, the future of fruit is in peril. Many scientists, organizations, and individuals are applying their imaginations and innovative ideas to ensure plants continue to be pollinated. For example, in last month’s blog post, we talked about what we can do in our own gardens to promote bee populations. In June 2020, one group of scientists proposed an innovative solution to compensate for the decreased number of pollinators in the short term: drones carrying bubble guns. 

Traditionally, when there are not enough bees or butterflies to pollinate a crop, humans can pollinate flowers using a pollen-soaked cotton swab or a small brush. However, this process is labour intensive and slow. Previously proposed methods for mechanically or robotically pollinating crops include spray dusters, pollen blowers, or small drones armed with pollen-coated brushes. However, these methods generally proved inefficient, expensive, or too rough to lay pollen on a small, delicate target.  

Enter bubble guns. Scientists at the Japan Advanced Institute of Science and Technology used bubble guns loaded with pollen solution mounted onto tiny, two-centimetre drones. As the autonomous drone flies around, it shoots bubbles at flowers. The bubbles pop gently on the flowers, leaving a pollen residue behind. The drones allow for automatic, accurate pollination, while the bubbles are gentle enough not to harm the delicate flowers. 

The inspiration for this idea? One of the scientists playing bubbles with his son. It just goes to show you…a flash of innovation can come from anywhere!  

By Michelle Campbell Mekarski

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Michelle Campbell Mekarski, PhD

As the Science Advisor at the Canada Science and Technology Museum, Michelle’s goal is to bridge the gap between the scientific community and the public — specializing in making science and technology engaging, accessible, and fun. Michelle earned a PhD in evolutionary biology and paleontology and has many years of experience developing and delivering science outreach activities. When away from her job at the museum, she can be found teaching at the University of Ottawa or Carleton University, digging for fossils, or relaxing by the water.

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Renée-Claude Goulet

Renée-Claude is the Science Advisor at the Canada Agriculture and Food Museum, and an Ontario Certified Teacher. Through her background in biology, education and many years of experience creating and delivering programs and exhibits at the museum, she has developed an expertise in communicating key issues related to the science and innovation behind production of food, fibre and fuel, to a wide range of audiences.

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Jesse Rogerson, PhD

Jesse is a passionate scientist, educator, and science communicator. As an assistant professor at York University in the Department of Science, Technology, and Society, he teaches three classes: History of Astronomy, Introduction to Astronomy, and Exploring the Solar System. He frequently collaborates with the Canada Aviation and Space Museum, and lends his expert voice to the Ingenium Channel. Jesse is an astrophysicist, and his research explores how super massive black holes evolve through time. Whether in the classroom, through social media, or on TV, he encourages conversations about how science and society intersect, and why science is relevant in our daily lives.

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Victoria Banderob

Inspired by science in everyday life, Victoria is passionate about engaging various publics with science to spark curiosity and exploration. Victoria is a science communication intern at the Canada Science and Technology Museum, and a graduate student in the Masters of Science Communication program at Laurentian University. She received her BSc from the University of Toronto in Health and Disease and Anthropology. If she’s not reading or writing about, well…science, you can find her painting or riding her bike through the streets of Toronto in search of the best cinnamon bun.