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If Launched by 2028, a Spacecraft Could Catch up With Oumuamua in 26 Years – Universe Today

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In October 2017, the interstellar object ‘Oumuamua passed through our Solar System, leaving a lot of questions in its wake. Not only was it the first object of its kind ever to be observed, but the limited data astronomers obtained as it shot out of our Solar System left them all scratching their heads. Even today, almost five years after this interstellar visitor made its flyby, scientists are still uncertain about its true nature and origins. In the end, the only way to get some real answers from ‘Oumuamua is to catch up with it.

Interestingly enough, there are many proposals on the table for missions that could do just that. Consider Project Lyra, a proposal by the Institute for Interstellar Studies (i4is) that would rely on advanced propulsions technology to rendezvous with interstellar objects (ISOs) and study them. According to their latest study, if their mission concept launched in 2028 and performed a complex Jupiter Oberth Manoeuvre (JOM), it would be able to catch up to ‘Oumuamua in 26 years.

On October 30th, 2017, less than two weeks after ‘Oumuamua was detected, the Initiative for Interstellar Studies (i4is) inaugurated Project Lyra. The purpose of this concept study was to determine if a mission to rendezvous with ‘Oumuamua was feasible using current or near-term technologies. Since then, the i4is team has conducted studies that considered catching up with the ISO using nuclear-thermal propulsion (NTP) and a laser sailcraft, similar to Breakthrough Starshot – an interstellar mission concept for reaching Alpha Centauri in 20 years.

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As they describe in their study, most of the previously proposed methods for reaching 1I/’Oumuamua using near-term technologies call for a Solar Oberth Manoeuvre (SOM). A perfect example is the “Sundiver,” a proposal made by researcher Coryn Bailer-Jones of the Max Planck Institute for Astronomy (MPIA). As he described to Universe Today in a previous article, this concept relies on the Sun’s radiation pressure to obtain a very high velocity with a light sail.

“The principle of the Oberth effect is to apply your boost when you are moving fastest relative to the body you are orbiting, which is the Sun in the case of the Sundiver,” he said. “The closer you are to the Sun in your orbit, the faster you will be. So to take advantage of the Oberth effect, you need to get as close to the Sun as possible.”

At the heart of the SOM and other Oberth maneuvers is a technique known as a Gravity Assist, which has been used to explore the Solar System since the early 1970s. This technique involves using the gravitational force of three bodies, including the spacecraft, a second body that provides the “assist” (typically a large planet), and the central body about which the spacecraft’s path is being controlled.

Adam Hibberd, a researcher with the i4is, was the lead author of this latest Lyra study (titled “Project Lyra: A Mission to 1I/’Oumuamua without Solar Oberth Manoeuvre.”) Before joining i4is, Hibberd was an aerospace engineer who developed the Optimum Interplanetary Trajectory Software (OITS). When ‘Oumuamua was detected, he decided to use OITS with this ISO as the intended destination. After finding out about Project Lyra, he joined them and their research efforts shortly afterward.

Artist’s impression of the Project Lyra lightsail probe rendezvousing with an interstellar object (ISO). Credit: i4is

As he explained to Universe Today via email, the Solar Oberth Maneuver (SOM) relies on three discrete changes in velocity (aka. impulses) to exit the Solar System. These include:

  1. At Earth, to increase the spacecraft’s fathest distance from the Sun (aphelion),
  2. At aphelion, to slow down and fall in close to the Sun,
  3. At the closest point to the Sun (perihelion) when the spacecraft is travelling at it fastest to get an extra boost

“This 3-impulse scenario was discovered by Theodore Edelbaum in 1959, although the term SOM seems to have stuck. It is fuel-optimal for generating high speeds out of the solar system. This is precisely what is needed to catch an ISO when the ISO has passed perihelion and is receding quickly from the sun.”

However, this theoretical setup disregards Jupiter. Thus as a slight modification to this, if we slow down in step 2 with the help of a reverse Jupiter gravitational assist, then we can achieve escape with even less fuel. It is because the SOM is so efficient at generating high speeds that it has been used to research missions to ISOs.”

Looking for alternatives to a SOM, Hibbert and his colleagues considered using a time-tested route that would incorporate Jupiter’s powerful gravitational pull. Part of their motivation for this was the inherent challenges a solar gravity assist maneuver presents. While this maneuver looks great on paper, it has never been executed before and therefore has a low Technology Readiness Level (TRL) rating.

The Interstellar Probe mission would be the farthest-reaching mission to date, overtaking the Voyager and New Horizons probes. Credit: NASA/JHUAPL

What’s more, there’s the issue of how much heating will take place as the lightsail achieves perihelion during step 3 (between 3 and 10 solar radii). These issues were addressed in a recent NASA Solar and Space Physics concept study titled “Interstellar Probe: Humanity’s Journey to Interstellar Space.” This study was conducted for the Solar and Space Physics 2023–2032 Decadal Survey, which included (among others) concepts for an interstellar probe. In Appendix D2.2., the study addresses thermal protection in the context of a Solar Oberth Maneuver:

“Unlike earlier missions, where a shield design was needed for a given Sun distance, the Interstellar Probe challenge is to see how close to the Sun a spacecraft can realistically get. As the solar distance decreases, the umbra angle increases and the size of the shield, relative to the spacecraft, grows significantly.

“Because a conceptual design effort cannot include all the material design, fabrication, and testing limitations of the full design, the final recommendation of allowable Sun distance is made based on where the design seems to be moving from very difficult to impossible.”

As the Parker Solar Probe amply demonstrates, getting close to the Sun requires a heat shield that can handle the extreme heat and radiation. In the case of Parker, that shield measures about 2.44 meters (8 ft) in diameter and weighs almost 72.5 kg (160 lbs). While the size and mass of a heat shield for Lyra would not be identical, it’s a fair bet that a solar heat shield would result in a lot of additional mass for the lightsail.

A swarm of laser-sail spacecraft leaving the Solar System. Credit: Adrian Mann

As an alternative, Hibberd and his team recommended a Jupiter Oberth Manoeuvre (JOM), which would launch from Earth, swing around Venus and Earth, conduct a Deep Space Maneuver (DSM), swing by Earth again, then receive a Gravity Assist using Jupiter’s gravitational pull. This is summarized by the acronym V-E-DSM-E-J, or the more commonly used V-E-E-GA – Venus, Earth, Earth, Gravity Assist. As Hibberd indicated, this maneuver would have several advantages over a SOM, among them:

“[It] would not require a heavy heat shield and also would not need: a) An extra travel distance from Jupiter to the Solar Oberth of around 5.2 astronomical units (au), [and] b) A further travel back to around Jupiter’s orbit of an additional 5.2 au. Both (a) & (b) would take time for a SOM which would not be required for a Jupiter Oberth Manoeuvre.”

“JOM is a discovery which is key to the remit of ‘Project Lyra’ to find options using ‘current or near-term technology’ as essentially it does not require any hardware or manoeuvres which have not been tried before, unlike the SOM. Nevertheless, despite the saving in time from not requiring (a) & (b) above – the lower escape speeds generated by the JOM mean the mission duration must be longer.”

Another advantage Hibberd and his team identified was the arrival speed of the spacecraft, which would be much slower than one relying on a SOM – 18 km/s (64,800 km/h; 40,265 mph) vs. 30 km/s (108,000 km/h; 67,108 mph). This would give the Project Lyra spacecraft more time to analyze ‘Oumuamua during approach and departure. Based on a launch window of 2028, they determined that a Project Lyra lightsail would be able to catch up to ‘Oumuamua by 2054.

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Given that ‘Oumuamua is the closest piece of interstellar material accessible to us, the scientific returns for a rendezvous mission would be immeasurable. For the relatively low cost of a rendezvous mission, humanity could get its first glimpse of what goes on in other star systems by mid-century. More to the point, it would be a chance to finally resolve the many questions’ Oumuamua raised when it made its historic flyby of Earth years ago!

Was it a nitrogen iceberg? Was it aliens? Was it something else entirely? If we play our cards right, we will know the answers to all of these questions by mid-century!

Further Reading: arXiv

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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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