Science
Green comet zooming our way, last visited 50,000 years ago


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A comet is streaking back our way after 50,000 years.
The dirty snowball last visited during Neanderthal times, according to NASA. It will come within 26 million miles (42 million kilometers) of Earth Wednesday before speeding away again, unlikely to return for millions of years.
So do look up, contrary to the title of the killer-comet movie “Don’t Look Up.”
Discovered less than a year ago, this harmless green comet already is visible in the northern night sky with binoculars and small telescopes, and possibly the naked eye in the darkest corners of the Northern Hemisphere. It’s expected to brighten as it draws closer and rises higher over the horizon through the end of January, best seen in the predawn hours. By Feb. 10, it will be near Mars, a good landmark.
Skygazers in the Southern Hemisphere will have to wait until next month for a glimpse.
While plenty of comets have graced the sky over the past year, “this one seems probably a little bit bigger and therefore a little bit brighter and it’s coming a little bit closer to the Earth’s orbit,” said NASA’s comet and asteroid-tracking guru, Paul Chodas.
Green from all the carbon in the gas cloud, or coma, surrounding the nucleus, this long-period comet was discovered last March by astronomers using the Zwicky Transient Facility, a wide field camera at Caltech’s Palomar Observatory. That explains its official, cumbersome name: comet C/2022 E3 (ZTF).
On Wednesday, it will hurtle between the orbits of Earth and Mars at a relative speed of 128,500 mph (207,000 kilometers). Its nucleus is thought to be about a mile (1.6 kilometers) across, with its tails extending millions of miles (kilometers).
The comet isn’t expected to be nearly as bright as Neowise in 2020, or Hale-Bopp and Hyakutake in the mid to late 1990s.


But “it will be bright by virtue of its close Earth passage … which allows scientists to do more experiments and the public to be able to see a beautiful comet,” University of Hawaii astronomer Karen Meech said in an email.
Scientists are confident in their orbital calculations putting the comet’s last swing through the solar system‘s planetary neighborhood at 50,000 years ago. But they don’t know how close it came to Earth or whether it was even visible to the Neanderthals, said Chodas, director of the Center for Near Earth Object Studies at NASA’s Jet Propulsion Laboratory in California.
When it returns, though, is tougher to judge.
Every time the comet skirts the sun and planets, their gravitational tugs alter the iceball’s path ever so slightly, leading to major course changes over time. Another wild card: jets of dust and gas streaming off the comet as it heats up near the sun.
“We don’t really know exactly how much they are pushing this comet around,” Chodas said.
The comet—a time capsule from the emerging solar system 4.5 billion years ago—came from what’s known as the Oort Cloud well beyond Pluto. This deep-freeze haven for comets is believed to stretch more than one-quarter of the way to the next star.
While comet ZTF originated in our solar system, we can’t be sure it will stay there, Chodas said. If it gets booted out of the solar system, it will never return, he added.
Don’t fret if you miss it.
“In the comet business, you just wait for the next one because there are dozens of these,” Chodas said. “And the next one might be bigger, might be brighter, might be closer.”
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Green comet zooming our way, last visited 50,000 years ago (2023, January 27)
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Science
Don’t Read Too Much into River Otters’ Return – Hakai Magazine


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Standing at the foot of a rocky sandstone cliff, biologist Michelle Wainstein inspected her essentials: latex gloves, two long cotton swabs, glass vials, and tubes filled with buffer solution. She placed them in a blue dry bag, rolled it up, and clipped it to a rope wrapped around her waist. It was late afternoon, and she was slick with dirt and sweat from navigating the dense terrain. Her destination lay across the frigid river: two small logs of otter fecal matter resting on a mossy boulder. In she plunged.
The river, the Green-Duwamish in Washington State, trickles out of the Cascade Range and empties 150 kilometers downstream into Puget Sound. The last eight kilometers of the run—known as the lower Duwamish—is so polluted the US Environmental Protection Agency designated it a Superfund site in 2001. For a century, Seattle’s aviation and manufacturing industries routinely dumped waste chemicals like polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) into the water.
“A lot of the river is still really polluted,” says Jamie Hearn, the Superfund program manager at Duwamish River Community Coalition. “The mud is thick and black, and you can smell it.”
Despite the pollution, river otters are everywhere along the waterway, even in the most contaminated areas near the river’s mouth. “I would be walking the docks looking for scat,” remembers Wainstein, “and a couple of times we were lucky enough to see moms with their pups.”
For several weeks in the summer of 2016 and 2017, Wainstein surveyed otter poop she collected from a dozen sites along the river. Comparing contaminant concentrations in the otters’ poop between the river’s industrial and rural zones, Wainstein uncovered the lingering legacy of the region’s toxic past. The poop from otters in the lower Duwamish contained nearly 26 times more PCBs and 10 times more PAHs than poop from their cousins in cleaner water upstream. PCBs disrupt hormonal and neurological processes and affect reproduction in mammals. Both PCBs and PAHs are human carcinogens.
The discovery that otters along the lower Duwamish are living with such high levels of contamination upends a common narrative: that river otters’ return to a once-degraded landscape is a sign that nature is healing.
In Singapore, where smooth-coated otters have reappeared in canals and reservoirs, they have been embraced as new national mascots. “It plays into that rhetoric that government agencies want to project,” says environmental historian Ruizhi Choo, “that we’ve done such a good job that nature is coming back. That image of a city in nature is the new marketing branding.”
In Europe, the once-common Eurasian otter similarly began reappearing in the late 20th century following successful river cleanup campaigns. Conservationist Joe Gaydos at the SeaDoc Society thinks that this phenomenon has helped form the mental link between otters and ecosystem health.
“The number of animals is our first indicator,” Gaydos says. But few seem to ask the next question: are those animals healthy?
As Wainstein’s study suggests, perhaps not. The otters she analyzed in the lower Duwamish have some of the highest concentrations of PCBs and PAHs ever recorded in wild river otters. Previous research has found a correlation between PCB exposure and health risks in wild river otters, including increased bone pathologies, reproductive and immunological disorders, organ abnormalities, and hormonal changes.
Even so, the contamination is not manifesting in physically obvious ways. “They’re not washing up on shore with tumors all over their bodies,” Wainstein says, and neither is their population dwindling. “They’re not setting off this direct alarm with a big change in their ability to survive.”
The otters’ ability to bear such a heavy contaminant burden suggests that a population resurgence alone may not reflect the quality of an environment. They just become as toxic as the environments they inhabit.
However, their localized bathroom habits, mixed diet of fish, crustaceans, and mammals, and persistence in the face of pollution make them useful indicators of environmental contamination.
River otters have played this role before. Following the 1989 Exxon Valdez oil spill, river otters lingered in oil-drenched waterways, allowing scientists like Larry Duffy at the University of Alaska Fairbanks to track the effectiveness of the oil cleanup. In 2014, scientists in Illinois discovered dieldrin in otter organ tissue even though the insecticide had already largely been banned for 30 years. In these cases, the collection of long-term pollution data was made possible by the creatures’ resilience in contaminated waterways. Wainstein wants to similarly use the Green-Duwamish River otters as biomonitors of the Superfund cleanup over the next decade.
Watching workers dismantle a portion of the river’s levied banks to make channels for salmon, Wainstein thinks about the seabirds, shorebirds, and small mammals, like beaver and mink, that were driven out by industrial contamination. She wonders if one day the rumbling machinery dredging up clawfuls of sediment from the riverbed will be taken over by the piercing cries of marbled murrelets, the croaks of tufted puffins, and the bubbling twittering of western snowy plovers.
“How long will it take? And will it actually work?” she says of the cleanup effort. The otters might hold the answer.
Science
Planets align on March 28 – CTV News London


If you had your eyes to the sky Tuesday evening you may have noticed a special alignment.
Just after sunset, Jupiter and Mercury were close to the horizon, just above that was the brightest planet Venus, a dim, greenish looking star was Uranus and a reddish/orange looking star was Mars.
This information is according to Jan Cami, a Professor in the Department of Physics & Astronomy at Western University, and the Director of the Hume Cronyn Memorial Observatory.
There were some clouds on the western horizon so the planets may have been difficult to see from this region.
According to Cami, the alignment was visible because of the layout of our solar system.
“All planets orbit the Sun in approximately the same plane, so you could think of the solar system as a pancake with an egg yolk at the centre that represents the Sun perhaps. The Earth of course is in that pancake, so if we look at other planets, we are always looking in that plane of the pancake, which to us looks like a line in the sky,” she told CTV News.
While it would have been interesting to see, Cami said to see the five planets fairly close to each other in the sky, is actually not super rare.
“They happen every couple of years. In fact, last June there was an alignment where the planets were visible early in the morning, in order of increasing distance from the Sun. What changes is the position of the planets. Having all eight planets of the solar system align like this is much rarer.”
If you happened to catch the alignment on camera, send us your photos and videos to weathersnapshot@ctv.ca
Science
UBCO students look up—way up—to gather research data – UBC Okanagan News – University of British Columbia


Atmospheric balloons are important tools for gathering information high above the earth in zones where people wouldn’t survive unless they wear pressurized suits.
When Lake Country’s Nolan Koblischke heard the American government was shooting down balloons suspected of spying, he was more than a little curious. The George Elliot Secondary graduate has sent one of those balloons into the atmosphere himself as a student at UBC Okanagan.
Atmospheric balloons are important tools for gathering information high above the earth in zones where people wouldn’t survive unless they wear pressurized suits. Most balloons collect climate data through radios, cameras and satellite navigation equipment—and are incapable of spying.
Koblischke, a fourth-year physics student, and Leonardo Caffarello are part of a UBCO physics and engineering team that launched a balloon to the stratosphere from a space centre in the Swedish Arctic last fall. The team, sponsored by School of Engineering Professor Jonathan Holzman, launched the balloon for a physics experiment to observe cosmic rays.
Koblischke said many people might be surprised at just how much you can learn from a balloon.
What are scientists learning from these atmospheric balloons?
These atmospheric balloons are a powerful and versatile tool for scientific research and exploration. Our balloon was launched in collaboration with Canadian and European agencies, so we were joined by other university and government agency teams from different countries.
Each team flying on the balloon had a different research objective and experiment. For instance, an Italian team was testing solar panels in the upper atmosphere to be used on satellites, a German space agency team was studying stratospheric chemistry and a Hungarian team was testing radiation sensors. We even saw an experiment to carry a telescope for atmosphere-free observations of space. Besides these applications, most balloons are used for weather purposes.
Is this the first time your project has left the ground?
No, the group was originally formed a few years ago by Caffarello and competed against other university teams in the Canadian Stratospheric Balloon Experiment Design Challenge. The UBCO student-led project was one of two experiments selected to fly onboard a high-altitude research balloon launched by the Canadian Space Agency in August 2019. The balloon was airborne at about 120,000 feet for 10 hours.
The project was working on a cosmic ray detection system and they were looking for different cosmic particles across the lower atmosphere. Caffarello has since graduated but led our team on the latest iteration of this experiment that took place in Sweden last fall.
Can you explain what you learned from the experiment last fall?
Our experiment was an innovative endeavour to detect cosmic rays in the stratosphere that Caffarello and I launched from the Esrange Space Center above the arctic circle in Sweden. We learned how to devise and construct an experiment that can withstand the severe conditions of near vacuum and extreme temperatures. We also gathered valuable data during the flight such as temperatures, pressure and images that proved that certain components of our experiment could work. Lastly, we realized that research requires perseverance and collaboration.
One of the most challenging moments was when we found an issue while preparing for the launch, a sudden failure during a pressure test. We worked until 4 am for three nights in a row, culminating in an all-nighter, to brainstorm solutions and design parts on the spot. Although we did not fully fix the problem, we remained resilient and worked diligently to resolve what we could and we were successfully approved for launch.
Cosmic rays sound dangerous
Cosmic rays can cause cancer by damaging DNA, but the chances are very small so you don’t need to lose sleep over it. Thankfully, our atmosphere blocks most of the highest energy cosmic rays, hence why we needed a balloon to get our experiment above much of the atmosphere, to try to detect more cosmic rays. You might have heard that you receive radiation when flying equivalent to a chest x-ray—cosmic rays are the reasons why.
What’s next for students at UBCO? Any more high-flying projects?
Yes, we have a student team called the UBCO StratoNeers who are currently participating in the Canadian Stratospheric Balloon Experiment Design Challenge. It’s the same competition Caffarello participated in back in 2019
The StratoNeers are testing hardware protective techniques to mitigate the occurrence of bit flips due to cosmic radiation in computer binary code. This experiment would provide new insights into protective techniques to safely store data onboard satellites, rovers and space telescopes.
Do you worry someone will shoot down your balloons?
We weren’t worried about our balloon being shot down. It did drift into Norway but thankfully the Norwegians didn’t mind.


Leonardo Caffarello, left, and Nolan Koblischke pose in front of their atmospheric balloon as it’s prepared for launch.
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