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Stalking Starlink's 'DarkSat' – Universe Today

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By now, you’ve no doubt heard of (or seen) Starlink. SpaceX’s mega-satellite constellation has become a permanent fixture in our skies as of late, with several routine passes on any given week. But have you seen the supposed ‘black sheep’ of the flock, DarkSat?

Starlink is looking to provide global internet access with latency (lag time) of 25/35 milliseconds, with connectivity speeds comparable to existing cable and fiber optic with services starting in late 2020. SpaceX recently announced that Starlink users will connect with the service via a ‘UFO on a Stick‘ antenna. (no kidding!)

Thus far, SpaceX has launched 182 Starlink satellites in three batches (that’s three times sixty, plus two early test satellites), and by the end of 2020, SpaceX will add nearly 1600 more satellites. SpaceX filed for 12,000 satellites to fill out the initial constellation, and there may ultimately be 42,000 Starlink satellites in low Earth orbit.

The first two Starlink test satellites set for launch. Credit: SpaceX

Each Starlink satellite is about the size of a table, and are flat-packed IKEA-style in the Falcon-9 nose fairing. Each satellite also sports a large solar panel that’s unfurled once they reach orbit.

60 Starlink satellites, stacked in a nose fairing for launch. Credit: SpaceX

Those numbers are also set to increase today, with the launch of Starlink 3 (batch number four) from Cape Canaveral Air Force station at 14:49 Universal Time (UT)/9:49 AM Eastern Standard Time (EST). SpaceX is now already the largest operator of satellites in low Earth orbit, and plans to reach a cadence of two Starlink launches a month, or one every two weeks.

The reality of ‘mega-satellite constellations’ such as Starlink in 2020 has also alarmed the astronomical community and generated controversy. Will artificial stars soon out number real ones in the night sky? This also comes as projects such as the Large Synoptic Survey Telescope (LSST) are set to come online in the coming years.

Starlink satellites trail through the field of view of the Dark Energy Camera. Credit: DELVE Survey/CTIO/AURA/NSF

The Rise of DarkSat

SpaceX made an
effort to address the issue during the November launch, and stated
that they painted one of the new Starlink satellites black in an
effort to reduce reflectivity. To date, SpaceX has not released
images of just what ‘DarkSat’ looks like up close. Several US
classified satellites such as Lacrosse 5 typically pull a ‘vanishing
act’ and are suspected of using some sort of stealth technology,
though of course, the U.S. Department of Defense isn’t sharing this
ability with SpaceX.

It took a while for
the identity of the rumored DarkSat to become general knowledge.
Typically, objects are cataloged by U.S. Combined Space Operations
Center (CSpOC) Space-Track shortly after launch, but the flood of new
objects generated by a typical Starlink launch poses a unique
challenge. The third batch launch (dubbed Starlink 2) that included
DarkSat put 60 objects in orbit.

T.S. Kelso over at Celestrak later identified DarkSat as NORAD ID 2020-001U (COSPAR ID 44932).

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A discussion panel at the recent 235th meeting of the American Astronomical Society addressed the Starlink issue. “The LSST survey is the most impacted by bright satellite trails because of its wide-fast-deep coverage of the sky,” Says Patrick Seitzer (University of Michigan) during the AAS panel on Starlink. “Original Starlinks will saturate detectors.” LSST is set to see first light in 2022.

Starlink with star trails over Virginia. Image credit and copyright: Chris Becke (@BeckePhysics)

The Starlink
satellites are also much more visible during original deployment than
when they reach operational orbits higher up. For comparison, the
original Iridium satellites were placed in an operational orbit 781
kilometers (485 miles) up, and where only visible to the naked eye
when they flared. The Starlink mega-constellation will deploy in
three orbital shells with operational altitudes of 340 kilometers
(210 miles), 550 kilometers (340 miles) and 1,150 kilometers (710
miles) respectively. As of writing this, DarkSat 2020-001U’s orbit
is still on the low end, at 366 by 368 kilometers. DarkSat should
reach operation altitude and orientation by the end of February 2020.

Like the Iridium
satellites, Starlink will also have an impact on the radio astronomy
end of the spectrum as well, something that’ll need to be
addressed.

What Observers are Seeing

Want to track Starlink and DarkSat for yourself? – All of the Starlink payloads are up on Heavens-Above on both the App and the website… this great utility is probably the easiest way to catch a Starlink pass. If you have the site configured for your location, simply look for a string of dawn or dusk passes, and watch the region of the sky noted during the given time. Note that the brightness of the Starlink satellite train seems to be heavily dependent on the viewing geometry: for example, we’ve seen lots of bright flaring flashes well into the negative magnitudes as the train passes the same spot in the sky when a pass is around 45 degrees in elevation opposite to the Sun, while the train seems to have the same steady brightness when passing directly overhead near the zenith. When the satellites are lower towards the horizon in the sunward direction, however, they are considerably fainter, and only visible with binoculars.

DarkSat ‘U’ compared to other Starlink satellites and bright stars. Credit and copyright: Thierry Legault.

“For the moment, nothing looks different between Darksat and the others,” veteran astrophotographer Thierry Legault told Universe Today. “When I filmed them, the units of the last launch were brighter than magnitude +2, that’s very bright!!!”

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If Starlink-3
launches on schedule Monday, we can expect a deployment of the next
60 satellites in a ‘string of pearls’ configuration about an hour
later. Using orbital TLEs provided by Dr. Marco Langbroek, we see
good dusk passes Monday night centered on:

Paris: 16:45 UT

Norfolk: 22:45 UT

St. Louis: 00:20 UT
(on January 28th).

Los Angeles: 1:54 UT (on January 28th).

Raining satellites: Starlink passes behind a tree, with star trails. Image credit and copyright: Marco Langbroek.

We managed to catch
a recent Starlink pass at dawn of the second batch launched in
November 2019 from here in Norfolk, Virginia as a set of two dozen
satellites equally spaced about five degrees apart caught the Sun’s
first rays passing out of the Earth’s shadow. They were also easily
visible to the naked eye, about as bright as the stars in the Big
Dipper asterism at magnitude +2.

Expect fielding an uptick in spurious UFO sightings versus Starlink as well. This is already happening, along with anomalous ‘mystery drone’ sightings out in the western U.S. OneWeb also plans to join the mega-satellite constellation game in 2020, with the launch of their first operational batch of 34 satellites from the Baikonur Cosmodrome in early February 2020. Based on the first test batch of six OneWeb satellites launched in February 2019 these satellites are much fainter at +8th magnitude, though these will still show up on deep sky images.

It’s strange that this is our new reality. Controversy notwithstanding, Starlink seems set to be a modern reality for the night sky, and backyard satellite trackers are playing a crucial role in documenting exactly what they are seeing as the modern mega-constellations unfurl overhead.

Follow us (@Astroguyz) on Twitter for latest updates on how to see the latest Starlink-4 satellite train in orbit.

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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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