Science
2021 will be the shortest year in decades. Here's why – CTV News
TORONTO —
Scientists say 2021 is expected to be a shorter year than normal with the Earth spinning at a faster rate than it has in the last 50 years.
York University astronomy and physics professor Paul Delaney explained to CTV’s Your Morning that as the Earth’s rotation speeds up, the shift means that time is slowing on the planet’s surface, making each day a “fraction of a second” shorter than 24 hours.
He said in an interview on Tuesday that this phenomenon is likely being caused by climate change.
“There is such [sic] a lot of ice that is becoming liquid and is flowing into the oceans, as a consequence of that you’re changing the way the mass on the surface of the Earth is situated. Instead of a really heavy mass around the pole, you’re melting it and [spreading] it all around the planet, and that is changing the way we are rotating on our axis,” Delaney said.
“When you bring the amount of material, the amount of mass, closer to our rotation axis that actually spins up our rotation rate a little bit faster.”
Delaney compared this shift in the Earth’s mass to that of figure skaters pulling their arms in closer to their body in order to spin faster.
However, he says this change does not mean the timing of one’s day-to-day activities will change.
“We’re talking about a fraction of a second here. People shouldn’t think they’re about to get an hour’s extra sleep as a result of this, but it really is associated with the melting of the polar ice caps,” he said.
While the planet’s rotational speed often drifts around slightly, Delaney said the melting of the ice caps with climate change can alter the global time frame as well as the marking of days.
Due to this increase in rotation speed, scientists report that the average day in 2021 is expected to be 0.05 milliseconds shorter than the 86,400 seconds that normally make up the 24-hour period.
Delaney says adding an extra second to clocks in what is called a leap second can help with this.
“The fraction of a second per day is not going to make much of a difference to you and me, but things like leap seconds have been introduced over the last sort of 40 to 50 years to compensate for this change in the Earth’s rotation rate compared to what we call our fixed frame,” Delaney said.
Delaney explained that leap seconds are irregular, with one second added to the last minute of a given calendar year. Since 1972, scientists have added leap seconds about every year-and-a-half, on average, according to the National Institute of Standards and Technology (NIST).
But with the Earth rotating faster over recent years, the International Earth Rotation and Reference Systems Service (IERS) says no leap seconds have been necessary since 2016.
IERS announced in July that no leap second would be added to the world’s official timekeeping in December 2020. However, a second may actually have to be subtracted in the future in what is known as a negative leap second, which would be a first for the IERS.
While the change in time may not affect every day activities, Delaney says atomic clocks used in GPS satellites do not consider the planet’s evolving motion, which can cause potentially confusing implications for smartphones, computers, and communications systems that synchronize with Network Time Protocol (NTP) servers.
“Most computer systems are expecting 60 seconds in a minute and when you get 61 seconds in a minute, then you can cause computer crashes, so it’s a little bit like having Y2K thrown around in a way that you just don’t expect,” Delaney said.
Because leap seconds are irregular, he says there may be only a “few weeks or a few months notice” that time will be added or subtracted. This can lead to computer glitches and crashes, which Delaney said is a “big problem in our very computerized society.”
Delaney added that this can also be a problem for stock markets. For example, he noted that the New York Stock Exchange went down for over an hour on June 30, 2015 because of a leap second.
“If you’re the person who is on the selling floor trying to transact millions if not billions of dollars, and the stock market disappears on you, you’re not going to be a very happy camper. So there is financial issues that are driving this whole question of leap seconds, and that brings into sharper focus the changing of the day,” Delaney said.
So, what can be done to help adjust the Earth’s rotation? Delaney said there isn’t much people can do.
“The Earth is doing what it wants to do. As we move around the sun, as we rotate on our axis, the rate at which we are rotating is completely independent of what you and I are wanting to do,” he said.
With ice caps melting as a result of climate change, Delaney said the “easy answer” would be to stop the global warming of the planet.
“Let’s keep the ice where it should be so that the rate of rotation is retained in the way that we’re expecting it to be,” he said.
Brenna Owen, The Canadian Press
Published Wednesday, April 24, 2024 7:27PM EDT
Last Updated Wednesday, April 24, 2024 7:27PM EDT
The artwork and publicity materials showcasing a giant salmon that lived five million years ago were ready to go to promote a new exhibit, when the discovery of two fossilized skulls immediately changed what researchers knew about the fish.
Initial fossil discoveries of the 2.7-metre-long salmon in Oregon in the 1970s were incomplete and had led researchers to mistakenly suggest the fish had fang-like teeth.
It was dubbed the “sabre-toothed salmon” and became a kind of mascot for the Museum of Natural and Cultural History at the University of Oregon, says researcher Edward Davis.
But then came discovery of two skulls in 2014.
Davis, a member of the team that found the skulls, says it wasn’t until they got back to the lab that he realized the significance of the discovery that has led to the renaming of the fish in a new, peer-reviewed study.
“There were these two skulls staring at me with sideways teeth,” says Davis, an associate professor in the department of earth sciences at the university.
In that position, the tusk-like teeth could not have been used for biting, he says.
“That was definitely a surprising moment,” says Davis, who serves as director of the Condon Fossil Collection at the university’s Museum of Natural and Cultural History.
“I realized that all of the artwork and all of the publicity materials and bumper stickers and buttons and T-shirts we had just made two months prior, for the new exhibit, were all out of date,” he says with a laugh.
Davis is co-author of the new study in the journal PLOS One, which renames the giant fish the “spike-toothed salmon.”
It says the salmon used the tusk-like spikes for building nests to spawn, and as defence mechanisms against predators and other salmon.
The salmon lived about five million years ago at a time when Earth was transitioning from warmer to relatively cooler conditions, Davis says.
It’s hard to know exactly why the relatives of today’s sockeye went extinct, but Davis says the cooler conditions would have affected the productivity of the Pacific Ocean and the amount of rain feeding rivers that served as their spawning areas.
Another co-author, Brian Sidlauskas, says a fish the size of the spike-toothed salmon must have been targeted by predators such as killer whales or sharks.
“I like to think … it’s almost like a sledgehammer, these salmon swinging their head back and forth in order to fend off things that might want to feast on them,” he says.
Sidlauskas says analysis by the lead author of the paper, Kerin Claeson, found both male and female salmon had the “multi-functional” spike-tooth feature.
“That’s part of our reason for hypothesizing that this tooth is multi-functional … It could easily be for digging out nests,” he says.
“Think about how big the (nest) would have to be for an animal of this size, and then carving it out in what’s probably pretty shallow water; and so having an extra digging tool attached to your head could be really useful.”
Sidlauskas says the giant salmon help researchers understand the boundaries of what’s possible with the evolution of salmon, but they also capture the human imagination and a sense of wonder about what’s possible on Earth.
“I think it helps us value a little more what we do still have, or I hope that it does. That animal is no longer with us, but it is a product of the same biosphere that sustains us.”
This report by The Canadian Press was first published April 24, 2024.
Science
Nasa's Hubble marks 34th anniversary with stunning view of Little Dumbbell Nebula – The Times of India
In celebration of its 34th anniversary, Nasa‘s Hubble Space Telescope has once again wowed astronomers and space enthusiasts alike by capturing an extraordinary image of the Little Dumbbell Nebula. This latest image offers a vivid glimpse into the complexities of a planetary nebula, demonstrating Hubble’s enduring capabilities in its extended mission.
The Little Dumbbell Nebula, also known as Messier 76, is one of the faintest objects in the Messier catalog and has intrigued astronomers for its intricate structure and dual-lobed shape. This planetary nebula, located approximately 2,500 light-years away in the constellation Perseus, represents a brief stage in the life cycle of a moderate-sized star like our sun.
Dr. Jennifer Wiseman, a senior scientist at Nasa’s Goddard Space Flight Center, expressed her admiration for the new imagery: “This beautiful nebula is what remains after a star like our own sun has exhausted the bulk of its nuclear fuel and shed its outer layers. The vibrant colors and intricate structures visible in the nebula are a telescope’s way of painting the portrait of the final stages of stellar evolution.”
The Little Dumbbell Nebula, despite its faintness, shines brightly in the detailed images provided by Hubble, allowing scientists to study aspects of the nebula that are rarely visible. The images highlight the dense, glowing gas and complex layers of material expelled from the dying star at the center of the nebula.
According to Dr. Wiseman, “Hubble’s high-resolution capabilities allow us to examine the fine details within the nebula, helping us understand how stars expel their material and the dynamics of this expulsion process. This image is more than just a picture; it’s a deep dive into the life of stars.”
Since its launch on April 24, 1990, Hubble has revolutionized our understanding of the universe, from the dynamics of galaxies to the atmospheres of exoplanets and the distribution of dark matter. Its contributions continue to support and complement data gathered by newer space observatories.
As Hubble continues its journey in space, the scientific community remains enthusiastic about the ongoing contributions it will bring to our understanding of the cosmos. Dr. Wiseman remarked, “Every image from Hubble is a new lesson in our cosmic curriculum.”
These observations not only contribute significantly to our knowledge of the life cycle of stars but also continue to highlight the critical role of Hubble in the exploration and understanding of our universe. As Hubble enters another year in orbit, its legacy of discoveries promises to keep inspiring both the scientific community and the public.
SpaceX sent up the 30th launch from the Space Coast for the year on the evening of April 23, a mission that also featured the company’s 300th successful booster recovery.
A Falcon 9 rocket carrying 23 of SpaceX’s Starlink internet satellites blasted off at 6:17 p.m. Eastern time from Cape Canaveral Space Force Station’s Space Launch Complex 40.
The first-stage booster set a milestone of the 300th time a Falcon 9 or Falcon Heavy booster made a successful recovery landing, and the 270th time SpaceX has reflown a booster.
This particular booster made its ninth trip to space, a resume that includes one human spaceflight, Crew-6. It made its latest recovery landing downrange on the droneship Just Read the Instructions in the Atlantic Ocean.
The company’s first successful booster recovery came in December 2015, and it has not had a failed booster landing since February 2021.
The current record holder for flights flew 11 days ago making its 20th trip off the launch pad.
SpaceX has been responsible for all but two of the launches this year from either Kennedy Space Center or Cape Canaveral with United Launch Alliance having launched the other two.
SpaceX could knock out more launches before the end of the month, putting the Space Coast on pace to hit more than 90 by the end of the year, but the rate of launches by SpaceX is also set to pick up for the remainder of the year with some turnaround times at the Cape’s SLC-40 coming in less than three days.
That could amp up frequency so the Space Coast could surpass 100 launches before the end of the year, with the majority coming from SpaceX. It hosted 72 launches in 2023.
More launches from ULA are on tap as well, though, including the May 6 launch atop an Atlas V rocket of the Boeing CST-100 Starliner with a pair of NASA astronauts to the International Space Station.
ULA is also preparing for the second launch ever of its new Vulcan Centaur rocket, which recently received its second Blue Origin BE-4 engine and is just waiting on the payload, Sierra Space’s Dream Chaser spacecraft, to make its way to the Space Coast.
Blue Origin has its own rocket it wants to launch this year as well, with New Glenn making its debut as early as September, according to SLD 45’s range manifest.
2024 Orlando Sentinel. Distributed by Tribune Content Agency, LLC.
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