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NASA confirms DART mission changed asteroid’s orbital period

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Asteroid moonlet Dimorphos as seen by the DART spacecraft 11 seconds before impact. Credit: NASA/Johns Hopkins APL

Edinburgh, 13 October 2022.NASA has concluded after careful analysis of data obtained over the past two weeks that the Double Asteroid Redirection Test (DART) mission was successful in altering Dimorphos’ orbit. DART was the first mission to purposely change the motion of a celestial object, demonstrating the planet’s asteroid deflection technology.

Before collision with the kinetic impactor, Dimorphos had an orbital period of 11 hours and 55 minutes around its parent asteroid, Didymos. After the intentional collision, astronomers measured how this orbital period changed. Earth-based telescopes have now confirmed that the impact altered Dimorphos’ orbit by 32 minutes, shortening it to 11 hours and 23 minutes.

Scientists are turning their focus on further analysis of the ejecta produced by the 22,530-kph collision. The sudden spring of asteroidal rock debris enhanced DART’s push against Dimorphos. Understanding the full effect of the blast requires information of the asteroid’s physical properties, which are still under investigation.

In about four years, the European Space Agency’s Hera project will conduct detailed surveys of both Dimorphos and Didymos, NASA said. The mission will have a particular focus on the crater left by DART while also measuring Dimorphos’ mass.

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NASA emphasised that neither Dimorphos nor Didymos poses any hazard to Earth before or after the DART mission.

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DUCHESS OF DIRT: Brown marmorated stink bugs have reached the Comox Valley – now what? – Comox Valley Record

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By Leslie Cox

Special to the Record

Thanks to all the wonderful readers who contacted me with sightings of the brown marmorated stink bug in their homes, on their decks, climbing the sides of their houses. I think it is safe to say the BMSBs are here in the valley. Ugh. Now what?

Well, we definitely need to think of doing something to control these pests because they are known to feed on more than 100 plant species. And since the BMSBs are native to Asia, there are not many predators here who will keep them in line.

RELATED: With the colder weather, beware of bugs seeking comfort indoors

No major beneficial insects to keep the BMSBs in check led to an estimated $37 million loss to the apple industry in the Mid-Atlantic States in 2010, so states a page on a Government of BC website titled “Brown Marmorated Stik Bug (BMSB) Pest Alert.” No mention of how large the apple industry is overall but a $37 million loss sounds significant.

Unfortunately, their appetite is not strictly for apples though. They also love pears, peaches, grapes, all kinds of berries, chokecherry, vegetables (including corn and tomatoes), hazelnuts, almonds, English holly, maple, box elder, white ash, catalpa, and buckthorn. I would hazard a guess there are likely even more plant species the BMSBs could develop a hunger for in their new country.

Thankfully, reproduction is not as prolific in North America when you compare one or two generations per year versus as many as six generations per year in their native Asia. But one gets the full scope of a population explosion when a single female BMSB can lay as many as 400 eggs in a summer and the second generation of females add their 400 eggs to the tally in the same season. Not as bad as the aphid reproduction numbers, but still robust enough.

As some readers have discovered, the adult BMSBs prefer warm, dry conditions where they can overwinter in comfort. As soon as the temperatures start to drop and daylight hours decrease, you may find these unwelcome house guests making themselves quite comfortable. They will not do any damage to your home, but evicting them can be daunting if there are enough of them. You certainly do not want to squish them or vacuum them up…or you will soon discover why they are labeled “stink bugs.” Not something you want to expose yourself to if you are sensitive to odours.

There is some good news, though. A species of parasitic wasp was found feasting on BMSB eggs in Chilliwack four years ago. Properly identified as Trissolcus japonicus, this wasp has managed to follow its favourite food source from its native Asia to Canada. Quite appropriately, this wasp is commonly called the Samurai wasp.

And according to the Government of BC website, ladybugs, lacewings and spiders will also feed on BMSB eggs. There may be some hope BMSBs will not become too unruly a pest.

Not so the American bullfrog, though. Just put another notch in my belt with the recent capture of yet another one in our pond. It was a decent size – about four inches from nose to butt. Definitely reproduction age but a male because of its yellow throat.

I suspect it was a late migration addition from the field pond behind us that made the mistake of doing a little sunbathing amongst the pond lilies on a nice afternoon when I spied him. Water was cold enough to slow his reactions though. Either that or my stalking skills with the butterfly net are getting quite good.

Leslie Cox co-owns Growing Concern Cottage Garden in Black Creek. Her website is www.duchessofdirt.ca.

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Scientists revive 48500-year-old ‘zombie virus’ buried in ice

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The thawing of ancient permafrost due to climate change may pose a new threat to humans, according to researchers who revived nearly two dozen viruses – including one frozen under a lake more than 48,500 years ago.

European researchers examined ancient samples collected from permafrost in the Siberia region of Russia. They revived and characterized 13 new pathogens, what they termed “zombie viruses,” and found that they remained infectious despite spending many millennia trapped in the frozen ground.

Scientists have long warned that the thawing of permafrost due to atmospheric warming will worsen climate change by freeing previously trapped greenhouse gases like methane. But its effect on dormant pathogens is less well understood.

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The team of researchers from Russia, Germany and France said the biological risk of reanimating the viruses they studied was “totally negligible” due to the strains they targeted, mainly those capable of infecting amoeba microbes. The potential revival of a virus that could infect animals or humans is much more problematic, they said, warning that their work can be extrapolated to show the danger is real.

“It is thus likely that ancient permafrost will release these unknown viruses upon thawing,” they wrote in an article posted to the preprint repository bioRxiv that hasn’t yet been peer-reviewed.

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“How long these viruses could remain infectious once exposed to outdoor conditions, and how likely they will be to encounter and infect a suitable host in the interval, is yet impossible to estimate.”

“But the risk is bound to increase in the context of global warming when permafrost thawing will keep accelerating, and more people will be populating the Arctic in the wake of industrial ventures,” they said.

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McMaster University team to finalize plans with CSA on deployment of satellite

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A team of students from McMaster University which has spent close to seven years creating a satellite to measure space radiation is set to finalize plans to deploy the device in outer space.

The Canadian Space Agency (CSA) is welcoming the developers this week to finalize preparation of their CubeSat, a miniaturized satellite to further the understanding of long-term exposure to space radiation.

Operation Team Lead with McMaster’s NEUtron DOSimetry & Exploration (NEUDOSE) mission Taren Ginter says the idea was selected for the Canadian Cube Sat project in 2018. In simple terms, Ginter says it measures the effects of ionizing radiation on the human body.

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Some of the financial backing for the project came in the form of $200,000 awarded to the McMaster developers by the CSA.

Ginter says as spaceflight and deep-space missions become a reality in the future, astronauts will likely have to face radiation that is distinct from the radiation experienced on earth.

The question the NEUDOSE mission is looking to answer is what kind and how much radiation astronauts will face on a multi-year mission in space.

“So our goal is to get a sense of those radiation differences and hopefully we can implement better safety precautions so that astronauts are protected,” Ginter explained.

The McMaster radiation detector is the size of a loaf of bread and is expected to be placed in a small satellite prior to being deployed into space, free floating like an astronaut would.

If it works properly, the device will send real-time radiation measurements back to the team at the university.

The device is the concept of Dr. Andrei Hanu, who came up with the idea while working at NASA as a research scientist.

Hanu led the first team of developers in 2015, jokingly referring to the device as the “igloo” due to its top which is dome-shaped.

However, Ginter says the satellite will actually look like a bunch of solar panels connected together due to the fact it needs to be charged by sunlight.

“But inside of the satellite, we have our charged and neutral particle tissue equivalent proportional counter, which is quite a mouthful,” Ginter said.

“So this is the actual payload of our satellite that will be looking at the radiation in low-earth orbit and then sending that information back down to ground station at McMaster.”

The NEUDOSE CubeSat will head to the CSA this week for a final step confirming it meets standards to be deployed from the International Space Station (ISS).

The life expectancy of the device is approximately one year in the Earth’s orbit after it’s been deployed.

The McMaster creation is earmarked for the ISS in February following launch from a SpaceX Dragon ship in Florida.

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