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ESA – ESA asteroid toolkit: how to guide

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Space Safety09/12/2022
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In brief

ESA’s Near-Earth Object Coordination Centre (NEOCC) – home to Europe’s team of experts keeping an eye on potentially risky asteroids – has developed four freely available tools to better understand the small bodies scattered through our Solar System, and the risk they pose Earth.

In-depth

The 375m Apophis was briefly an object of concern when in 2004 it appeared to have a 2.7% chance of striking Earth on 13 April 2029. Later observations ruled this out entirely. It will however pass very close to Earth, and will be visible around the globe.

With the new near-Earth object (NEO) Toolkit you can visualise any asteroid’s orbit, including those making a close approach of Earth; get impressive illustrations of different groups and families of asteroids as well as plan upcoming observations and chart asteroids paths across the sky from any location in the world.

Freely available via neo.ssa.esa.int/neo-toolkit, the tools are for professional and amateur astronomers alike, along with journalists, media and schools looking for accurate visuals and anyone with an interest in asteroids.

The NEO Toolkit includes the Observation Planning Tool, Sky Chart Display Tool, Orbit Visualisation Tool and the Flyby Visualisation Tool.

Using the infamous Apophis asteroid as a case study, find out below how to get started.

Orbit Visualisation Tool

The Orbit Visualisation Tool allows you to visualise individual asteroid orbits or see groups of asteroids in orbit based on their asteroid group, family, spectral class or observation priority. To get started, click on the arrow next to “Select objects” at the upper left of the screen to make your selection.

NEO Groups

All near-Earth objects fall into one of four groups: Atira, Aten, Apollo or Amor. This depends on their orbital period – the time it takes for one full rotation around the Sun – and whether their orbit crosses Earth’s own.

Apophis, our case study, is for example an Aten asteroid as it has an orbital period shorter than Earth’s but still crosses Earth’s own path around the Sun. After its close flyby of Earth in 2029 however, Apophis’s orbit will be shifted enough by our planet’s gravity that it will fall into a different category: becoming an Apollo asteroid.

Known Aten asteroids in orbit around the Sun (size not to scale), using ESA’s Orbit Visualisation Tool

Asteroid families

Asteroids are grouped into a family if they share orbital characteristics, such as the shape of their orbit (eccentricity) or how ‘high’ they rise from the orbital plane (orbital inclination). However, families of asteroids are also thought to have originated from the same original object. As fragments from past asteroid collisions, they are the leftovers of a much larger asteroid, a failed planet.

Spectral class

An asteroid is classified with a specific spectral class depending on the sunlight it reflects; its particular emission spectrum, colour and sometimes its albedo (brightness). From this, astronomers get insights into the composition of an asteroid’s surface. Apophis, for example, is classified as an S-class asteroid, because of its stony composition.

Observational priority

Asteroids on ESA’s Asteroid Risk List – the ever-changing list of asteroids that have a ‘non-zero’ chance of impact in the next hundred years – can also be selected. That’s right, more than 95% of known near-Earth asteroids have no chance of impact in a decade. The rest are being closely monitored, until experts have enough data to say for certain they will not strike.

Flyby Visualisation Tool

With the Flyby Visualisation Tool, any asteroid that will come within three lunar distances of Earth can be easily visualised as it makes its close approach. Flybys past, present and future can be conjured up, showing how an asteroid’s path bends and warps as it gets near our planet and past it.

Search for any asteroid flyby over a given time period, or if you have a specific asteroid in mind simply click “Edit my list of objects” and add it to your list.

Apophis will make a close Earth approach on 13 April 2029. By choosing a start date of 1 Jan 2029 and an end date of 31 Dec 2029, all flybys currently known within three lunar distances from Earth for that year appear, including (99942) Apophis. Alternatively, add the asteroid to your selected objects to filter just for Apophis flybys.

Representation of Apophis’ close approach to Earth in 2029, with ESA’s Flyby Visualisation Tool

Apophis’ path five days before and five days after closest approach can be played out using the media buttons under the image. The moment of close approach is coloured red at the centre of the time bar, and various options are available to alter the view, from altering the speed to zooming in or out on Earth or on the asteroid, inverting the colours and adding or removing various details on screen.

Share your search results using the share button on the top left. Session data will be stored for 30 days. You can take a screenshot or movie of what you’re looking at using the “Export” button on the right.

Observation Planning Tool

The Observation Planning Tool can be used to check if and when an asteroid will be visible from any location on Earth, and when you’ll have the very best conditions for upcoming asteroid observations.

The tool can be used for any date(s), but it provides precalculated physical data and ‘ephemerides’ (a table showing the trajectory of an object over time) for observations within 30 days from the present date. Further into the future than this the planning tool still works but will take a bit longer to finish the calculation of all ephemerides.

This tool considers multiple variables over the timeframe selected that affect an asteroid’s visibility, including the relative position of the Sun, Moon and Galaxy, the sky’s movement, the density of the stars and the visibility and limitations of the telescope being used.

Under the “Setup” tab, add the date range in which you are interested, the location of the “observatory” (you!) and add the asteroid or asteroids of interest. Click “Go to Filtering”.

Under the Filtering tab you’ll find the list of asteroids selected and the visibility data in a graph format. Select your ‘time step’, i.e. the time interval between observations you’d like to check, and click “Calculate ephemerides”.

To find out if and when Apophis will be visible over the month of January 2023, the following observation data was provided by the tool.

ESA’s Observation Planning Tool shows five days in which Apophis will be visible from Darmstadt, Germany in January 2023

At the time this guide was prepared, asteroid Apophis was just over 200 million km from Earth. The Observation Planning Tool shows that Apophis will be visible for five days in the month of January 2023, seen from Darmstadt, Germany, under certain conditions shown in the bars on the left-hand side.

Use the sliders to filter for the viewing conditions acceptable for the capabilities of your telescope.

Moon elongation describes the Moon’s angular distance from the asteroid in question, as seen from the Earth (the vertex of the angle).

Sun elongation similarly describes the angular distance between the Sun and the asteroid to be observed.

Sky movement describes the speed of near-Earth objects in the sky with respect to the background stars.

Magnitude describes the evolution of the apparent magnitude of the selected asteroid in the sky during the period selected.

Galactic Latitude is measured in degrees north or south of the Galaxy’s fundamental plane of symmetry. This plane is defined by the galactic equator, the great circle in the sky best fitting the plane of the Milky Way, as determined by a combination of optical and radio measurements.

The density of stars changes as asteroids move through the sky and their background constantly changes. This measure refers to the number of stars per square arcminute in the area surrounding the selected asteroid.

Sky Chart Display Tool

Finally, with the Sky Chart Display tool, you can see where near-Earth asteroids will appear in the night sky from any location on Earth. You can visualise a particular day or extend an asteroid’s path through time to see how it will move across the sky.

Select the timeframe in which you will be observing and your location, and then add the asteroid(s) of interest. Either chose ‘Topocentric’ for a view from a point on Earth’s surface or ‘Geocentric’ for a view from Earth’s centre.

Click on “Go to Visualisation” to create your asteroid sky chart. Note: For dates far in the future, it will take some time for the sky chart tool to load.

In the case of Apophis, our case study, 1-31 January 2023 were selected to create this view, with intervals every two days as seen from Darmstadt, Germany

This sky chart for Apophis was created for the month of January 2023, daily markers every two days and the observer located in Darmstadt, Germany.

Use the ‘Display settings’ on the top-right to add or remove features such as coordinate grids and telescope parameters or to alter look of the asteroid trail. Add or remove constellations and deep sky objects by clicking on “Background objects” and decrease or increase the Field of View using the sliding bar on the bottom right.

Click “Print” on the right to save what you see.

We hope you enjoy the NEO Toolkit!

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Here’s how Helene and other storms dumped a whopping 40 trillion gallons of rain on the South

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More than 40 trillion gallons of rain drenched the Southeast United States in the last week from Hurricane Helene and a run-of-the-mill rainstorm that sloshed in ahead of it — an unheard of amount of water that has stunned experts.

That’s enough to fill the Dallas Cowboys’ stadium 51,000 times, or Lake Tahoe just once. If it was concentrated just on the state of North Carolina that much water would be 3.5 feet deep (more than 1 meter). It’s enough to fill more than 60 million Olympic-size swimming pools.

“That’s an astronomical amount of precipitation,” said Ed Clark, head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama. “I have not seen something in my 25 years of working at the weather service that is this geographically large of an extent and the sheer volume of water that fell from the sky.”

The flood damage from the rain is apocalyptic, meteorologists said. More than 100 people are dead, according to officials.

Private meteorologist Ryan Maue, a former NOAA chief scientist, calculated the amount of rain, using precipitation measurements made in 2.5-mile-by-2.5 mile grids as measured by satellites and ground observations. He came up with 40 trillion gallons through Sunday for the eastern United States, with 20 trillion gallons of that hitting just Georgia, Tennessee, the Carolinas and Florida from Hurricane Helene.

Clark did the calculations independently and said the 40 trillion gallon figure (151 trillion liters) is about right and, if anything, conservative. Maue said maybe 1 to 2 trillion more gallons of rain had fallen, much if it in Virginia, since his calculations.

Clark, who spends much of his work on issues of shrinking western water supplies, said to put the amount of rain in perspective, it’s more than twice the combined amount of water stored by two key Colorado River basin reservoirs: Lake Powell and Lake Mead.

Several meteorologists said this was a combination of two, maybe three storm systems. Before Helene struck, rain had fallen heavily for days because a low pressure system had “cut off” from the jet stream — which moves weather systems along west to east — and stalled over the Southeast. That funneled plenty of warm water from the Gulf of Mexico. And a storm that fell just short of named status parked along North Carolina’s Atlantic coast, dumping as much as 20 inches of rain, said North Carolina state climatologist Kathie Dello.

Then add Helene, one of the largest storms in the last couple decades and one that held plenty of rain because it was young and moved fast before it hit the Appalachians, said University of Albany hurricane expert Kristen Corbosiero.

“It was not just a perfect storm, but it was a combination of multiple storms that that led to the enormous amount of rain,” Maue said. “That collected at high elevation, we’re talking 3,000 to 6000 feet. And when you drop trillions of gallons on a mountain, that has to go down.”

The fact that these storms hit the mountains made everything worse, and not just because of runoff. The interaction between the mountains and the storm systems wrings more moisture out of the air, Clark, Maue and Corbosiero said.

North Carolina weather officials said their top measurement total was 31.33 inches in the tiny town of Busick. Mount Mitchell also got more than 2 feet of rainfall.

Before 2017’s Hurricane Harvey, “I said to our colleagues, you know, I never thought in my career that we would measure rainfall in feet,” Clark said. “And after Harvey, Florence, the more isolated events in eastern Kentucky, portions of South Dakota. We’re seeing events year in and year out where we are measuring rainfall in feet.”

Storms are getting wetter as the climate change s, said Corbosiero and Dello. A basic law of physics says the air holds nearly 4% more moisture for every degree Fahrenheit warmer (7% for every degree Celsius) and the world has warmed more than 2 degrees (1.2 degrees Celsius) since pre-industrial times.

Corbosiero said meteorologists are vigorously debating how much of Helene is due to worsening climate change and how much is random.

For Dello, the “fingerprints of climate change” were clear.

“We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. And there would have been a time when a tropical storm would have been heading toward North Carolina and would have caused some rain and some damage, but not apocalyptic destruction. ”

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Follow AP’s climate coverage at https://apnews.com/hub/climate

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Follow Seth Borenstein on Twitter at @borenbears

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Associated Press climate and environmental coverage receives support from several private foundations. See more about AP’s climate initiative here. The AP is solely responsible for all content.

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‘Big Sam’: Paleontologists unearth giant skull of Pachyrhinosaurus in Alberta

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It’s a dinosaur that roamed Alberta’s badlands more than 70 million years ago, sporting a big, bumpy, bony head the size of a baby elephant.

On Wednesday, paleontologists near Grande Prairie pulled its 272-kilogram skull from the ground.

They call it “Big Sam.”

The adult Pachyrhinosaurus is the second plant-eating dinosaur to be unearthed from a dense bonebed belonging to a herd that died together on the edge of a valley that now sits 450 kilometres northwest of Edmonton.

It didn’t die alone.

“We have hundreds of juvenile bones in the bonebed, so we know that there are many babies and some adults among all of the big adults,” Emily Bamforth, a paleontologist with the nearby Philip J. Currie Dinosaur Museum, said in an interview on the way to the dig site.

She described the horned Pachyrhinosaurus as “the smaller, older cousin of the triceratops.”

“This species of dinosaur is endemic to the Grand Prairie area, so it’s found here and nowhere else in the world. They are … kind of about the size of an Indian elephant and a rhino,” she added.

The head alone, she said, is about the size of a baby elephant.

The discovery was a long time coming.

The bonebed was first discovered by a high school teacher out for a walk about 50 years ago. It took the teacher a decade to get anyone from southern Alberta to come to take a look.

“At the time, sort of in the ’70s and ’80s, paleontology in northern Alberta was virtually unknown,” said Bamforth.

When paleontogists eventually got to the site, Bamforth said, they learned “it’s actually one of the densest dinosaur bonebeds in North America.”

“It contains about 100 to 300 bones per square metre,” she said.

Paleontologists have been at the site sporadically ever since, combing through bones belonging to turtles, dinosaurs and lizards. Sixteen years ago, they discovered a large skull of an approximately 30-year-old Pachyrhinosaurus, which is now at the museum.

About a year ago, they found the second adult: Big Sam.

Bamforth said both dinosaurs are believed to have been the elders in the herd.

“Their distinguishing feature is that, instead of having a horn on their nose like a triceratops, they had this big, bony bump called a boss. And they have big, bony bumps over their eyes as well,” she said.

“It makes them look a little strange. It’s the one dinosaur that if you find it, it’s the only possible thing it can be.”

The genders of the two adults are unknown.

Bamforth said the extraction was difficult because Big Sam was intertwined in a cluster of about 300 other bones.

The skull was found upside down, “as if the animal was lying on its back,” but was well preserved, she said.

She said the excavation process involved putting plaster on the skull and wooden planks around if for stability. From there, it was lifted out — very carefully — with a crane, and was to be shipped on a trolley to the museum for study.

“I have extracted skulls in the past. This is probably the biggest one I’ve ever done though,” said Bamforth.

“It’s pretty exciting.”

This report by The Canadian Press was first published Sept. 25, 2024.

The Canadian Press. All rights reserved.

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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

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TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.

Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.

Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.

The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.

The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.

It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.

Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.

Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.

Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.

Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.

Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.

The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”

The Canadian Press. All rights reserved.

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