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'Time Machine' Simulation May Uncover Secrets of Cosmic Web Connecting Universe – VICE

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When light from the early universe reaches Earth, it presents an eerie snapshot of ancient stars and galaxies that have long since died, or taken on different forms over the course of billions of years. 

Though we cannot directly see the future of these objects, scientists have now figured out how to do the next best thing by “fast-forwarding” simulations of the cosmic web, a network of large-scale structures that connects the universe, over the course of 11 billion years to its present state, reports a new study.

In this way, researchers led by Metin Ata, a cosmologist at the University of Tokyo’s Kavli Institute for the Physics and Mathematics of the Universe, were able to unspool the long-term evolution of giant galaxy clusters like a “time machine,” in the words of one author.

The new technique allowed the team “to ‘fast-forward’ the simulation to our present day and study the evolution of observed cosmic structures self-consistently,” revealing that at least one of these ancient “protoclusters” likely collapsed into an enormous cosmic web filament spanning 300 million light years, according to a study published in Nature Astronomy on Thursday.  

The results also provide a means to test the standard model of cosmology, alternately known as the Lambda cold dark matter (ΛCDM), which is a well-corroborated framework to explain the weird properties of the universe, including the existence of dark matter, an unexplained substance that is far more abundant than regular “baryonic” matter.

“Understanding the formation of large-scale structures in the Universe, starting from tiny fluctuations in the matter density and subsequently evolving gravitationally into the complex cosmic web seen at the present epoch, is a key ambition of cosmological science,” Ata and his colleagues said in the study.

“As gravitationally evolving objects, protoclusters are ideal observables to study early structure formation and to compare with theoretical predictions,” they continued, adding that they are “excellent laboratories to jointly study the interplay between baryonic physics and dark matter models.”

Most cosmological simulations match the general statistical distribution of matter across the universe, rather than reproducing any specific cosmic structures that we can observe from Earth. However, a subcategory of these models, known as constrained cosmological simulations, do mimic real observations, though the new study notes that they are “mainly focused on the local universe or nearby structures” rather than the distant ancient universe, which is called the “high-redshift” universe  because light waves from this era become stretched into redder bands of the spectrum over time.

By merging constrained cosmological simulations with the Hubble Space Telescope’s Cosmological Evolution Survey (COSMOS), Ata’s team capitalized on what they call “a unique opportunity for studying early structure formation and matching galaxy properties” between the ancient and modern universe, according to the study.

“Observationally, the effort to find and characterize protoclusters is a lively, ongoing field,” the researchers said. “In particular, the COSMOS field is an excellent site for this, as it is covered by deep and coordinated multi-wavelength observations over a wide field” that are “suited to protocluster studies.”

“Up to this point, there has not been a uniform and self-consistent study dedicated to these structures in the COSMOS field,” the team continued. “We address this problem with constrained simulations applied towards the rich legacy of large-scale spectroscopic surveys that have been conducted on the COSMOS field over nearly a decade, achieving a cosmic volume and number density unmatched anywhere else on the sky.”

In other words, the researchers looked at real protoclusters that existed 11 billion years ago and turned the clock forward in their constrained simulations. Of particular interest was the fate of the Hyperion super-protocluster, the largest structure of its kind during cosmic dawn, which the team called “the subject of scientific and public curiosity” in the study. Whereas some scientists have speculated that this immense elongated structure would eventually collapse into a single massive galaxy cluster, Ata and his colleagues suggest that it has evolved into a giant filamentary supercluster within the cosmic web, which is embedded with multiple massive cluster cores.

“We confirm that several previously reported protoclusters will evolve into massive galaxy clusters by our present epoch, including the ‘Hyperion’ structure that we predict will collapse into a giant filamentary supercluster spanning 100 [megaparsecs],” or 300 million light years, the team said in the study. “We also discover previously unknown protoclusters with lower final masses than are typically detectable by other methods that nearly double the number of known protoclusters within this volume.”

The large-scale structures that undergird the cosmic web are mostly made of dark matter, which is only observable due to its gravitational effect on luminous objects made of regular baryonic matter. As a result, the simulations pioneered by the new study can help shed light on the nature of dark matter by charting the course of its cosmic distribution across time, providing a key test of the ΛCDM model.

“Constrained simulations of these upcoming high-redshift galaxy surveys will also allow us to probe early structure formation for consistency with the ΛCDM model with increasing sensitivity to lower-mass galaxy (proto)clusters,” the researchers said in the study. 

“Each identified protocluster represents a unique environment to study the morphologies and merger rates of member galaxies in high-density environments” in the early universe, they concluded, “which is so far only possible in theoretical studies or random cosmological simulations.”

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Artemis 1 moon mission could launch as soon as late August – Space.com

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NASA officials have declared the Artemis 1 moon rocket’s most recent “wet dress rehearsal” a success and are hopeful the mission can get off the ground as soon as late August.

The Artemis 1 stack — a Space Launch System (SLS) rocket topped by an Orion capsule — is scheduled to roll back to the Vehicle Assembly Building (VAB) at NASA’s Kennedy Space Center (KSC) in Florida on July 1, where the massive vehicle will undergo repairs and preparations for its coming launch. 

Artemis 1, the first launch for the SLS, will send an uncrewed Orion on a roughly month-long mission around the moon. The mission has experienced several delays, and most recently the rocket’s certification to fly has been held up by incomplete fueling tests — a key part of the wet dress rehearsal, a three-day series of trials designed to gauge a new vehicle’s readiness for flight. 

Related: NASA’s Artemis 1 moon mission explained in photos 

The Artemis 1 stack first rolled from the VAB to KSC’s Pad 39B in mid-March, to prep for a wet dress rehearsal that began on April 1. But three separate attempts to fill the SLS with cryogenic propellants during that effort failed, sending the stack back to the VAB for repairs on April 25. The most recent wet dress try, which wrapped up on Monday (June 20), didn’t go perfectly, but NASA has deemed it good enough to proceed with preparations for launch.

Operators were able to fully fuel SLS for the first time, bringing the launch simulation much further along than any of the attempts in April. A leak from the core stage’s engine cooling system “umbilical” line was detected during Monday’s fueling test, but mission managers determined that the deviation didn’t pose a safety risk and continued with the simulation’s terminal count. That ended up being the right decision, Artemis 1 team members said.  

Mission operators were able to run a “mask” for the leak in the ground launch sequencer software, which permitted computers in mission control to acknowledge the malfunction without flagging it as a reason to halt the countdown, according to Phil Weber, senior technical integration manager at KSC. Weber joined other agency officials on a press call Friday (June 24) to discuss the plans for Artemis 1 now that the wet dress is in the rear view mirror.

The software mask allowed the count to continue through to the handoff from the mission control computers to the automated launch sequencer (ALS) aboard the SLS at T-33 seconds, which ultimately terminated the count at T-29 seconds. 

“[ALS] was really the prize for us for the day,” Weber said during Friday’s call. “We expected … it was going to break us out [of the countdown] because the ALS looks for that same measurement, and we don’t have the capability to mask it onboard.” 

It was unclear immediately following the recent wet dress if another one would be required, but mission team members later put that question to rest.

“At this point, we’ve determined that we have successfully completed the evaluations and required work we intended to complete for the dress rehearsal,” Tom Whitmeyer, deputy associate administrator for Common Exploration Systems at NASA headquarters, said on Friday’s call. He added that NASA teams now have the “go ahead to proceed” with preparations for Artemis 1’s launch.

Before it can be rolled back to the VAB, however, the stack will undergo further maintenance at Pad 39B, including repairs to the quick-disconnect component on the aft SLS umbilical, which was responsible for Monday’s hydrogen leak. 

There’s also one more test technicians need to perform at the pad. Hot-firing the hydraulic power units (HBUs), part of the SLS’ solid rocket boosters, was originally part of the wet dress countdown but was omitted when the countdown was aborted. Those tests will be completed by Saturday (June 25), according to Lanham. Following the hot-fire tests, operators will then spend the weekend offloading the HBUs’ hydrazine fuel.

Once back in the VAB, NASA officials estimate it’ll take six to eight weeks of work to get Artemis 1 ready to roll back to Pad 39B for an actual liftoff. Cliff Lanham, senior vehicle operations manager at KSC, outlined some of the planned maintenance on Friday’s call. 

Related: NASA’s Artemis program of lunar exploration

Related stories:

Among other tasks, technicians will perform standard vehicle inspections, hydrogen leak repairs, “late-stow” for the payloads flying on Orion, and software loads to the SLS core stage and upper stage. They will also install flight batteries.

“Ultimately, we want to get to our flight termination system testing,” Lanham said. “Once that’s complete, we’ll be able to perform our final inspections in all the volumes of the vehicle and do our closeouts.”

After that work is complete, the Artemis 1 stack will roll out from the VAB once again, making the eight to 11-hour crawl back to Pad 39B on July 1. Whitmeyer said on Friday that the late-August launch window for Artemis 1, which opens on Aug. 23 and lasts for one week, is “still on the table.”

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Mars Express Is Getting a Long-Overdue Software Upgrade – PCMag

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The European Space Agency (ESA) is updating the software on a critical part of the Mars Express spacecraft for the first time since it was deployed to the Red Planet in 2003.

ESA says(Opens in a new window) the Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) instrument “is receiving a major software upgrade that will allow it to see beneath the surfaces of Mars and its moon Phobos in more detail than ever before.” And that is no small feat.

“We faced a number of challenges to improve the performance of MARSIS,” Enginium’s Carlo Nenna said in a statement. “Not least because the MARSIS software was originally designed over 20 years ago, using a development environment based on Microsoft Windows 98!”

But Enginium and the Italian National Institute for Astrophysics, which operates MARSIS, overcame those challenges. ESA says that it’s now implementing the updated MARSIS software on Mars Express to help it search for signs of liquid water deep beneath the planet’s surface.

“The new software will help us more quickly and extensively study these regions in high resolution and confirm whether they are home to new sources of water on Mars,” ESA Mars Express scientist Colin Wilson said in a statement. “It really is like having a brand new instrument on board Mars Express almost 20 years after launch.”

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All of which means that new software is being deployed to a nearly 20-year-old instrument, which was originally developed on Windows 98, on a planet that is typically about 140 million miles away. Keep that in mind the next time you’re prompted to install an update for your device.

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5 planets align in night sky for first time in years – CTV News

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A rare, five-planet alignment will peak on June 24, allowing a spectacular viewing of Mercury, Venus, Mars, Jupiter and Saturn as they line up in planetary order.

The event began at the beginning of June and has continued to get brighter and easier to see as the month has progressed, according to Diana Hannikainen, observing editor of Sky & Telescope.

A waning crescent moon will be joining the party between Venus and Mars on Friday, adding another celestial object to the lineup. The moon will represent the Earth’s relative position in the alignment, meaning this is where our planet will appear in the planetary order.

This rare phenomenon has not occurred since December 2004, and this year, the distance between Mercury and Saturn will be smaller, according to Sky & Telescope.

HOW TO VIEW THE ALIGNMENT

Stargazers will need to have a clear view of the eastern horizon to spot the incredible phenomenon, Hannikainen said. Humans can view the planetary show with the naked eye, but binoculars are recommended for an optimal viewing experience, she added.

The best time to view the five planets is in the one hour before sunrise, she said. The night before you plan to view the alignment, check when the sun will rise in your area.

Some stargazers are especially excited for the celestial event, including Hannikainen. She flew from her home west of Boston to a beachside town along the Atlantic Ocean to secure an optimal view of the alignment.

“I’ll be out there with my binoculars, looking towards the east and southeast and crossing all my fingers and toes that it is going to be clear,” Hannikainen said.

You don’t have to travel to catch a glimpse of the action because it will be visible to people around the globe.

Stargazers in the Northern Hemisphere can see the planets from the eastern to southeastern horizon while those in the Southern Hemisphere should look along the eastern to northeastern horizon. The only requirement is a clear sky in the direction of the alignment.

By the next day, the moon will have continued its orbit around the Earth, moving it out of alignment with the planets, she said.

If you miss the five-planet alignment in sequential order, the next one will happen in 2040, according to Sky & Telescope.

There will be seven more full moons in 2022, according to The Old Farmers’ Almanac:

  • June 14: Strawberry moon
  • July 13: Buck moon
  • Aug. 11: Sturgeon moon
  • Sept. 10: Harvest moon
  • Oct. 9: Hunter’s moon
  • Nov. 8: Beaver moon
  • Dec. 7: Cold moon

These are the popularized names associated with the monthly full moons, but the significance of each one may vary across Native American tribes.

LUNAR AND SOLAR ECLIPSES

There will be one more total lunar eclipse and a partial solar eclipse in 2022, according to The Old Farmer’s Almanac.

Partial solar eclipses occur when the moon passes in front of the sun but only blocks some of its light. Be sure to wear proper eclipse glasses to safely view solar eclipses, as the sun’s light can be damaging to the eye.

A partial solar eclipse on Oct. 25 will be visible to those in Greenland, Iceland, Europe, northeastern Africa, the Middle East, western Asia, India and western China. Neither of the partial solar eclipses will be visible from North America.

A total lunar eclipse will also be on display for those in Asia, Australia, the Pacific, South America and North America on Nov. 8 between 3:01 a.m. ET and 8:58 a.m. ET — but the moon will be setting for those in eastern regions of North America.

METEOR SHOWERS

Check out the remaining 11 showers that will peak in 2022:

  • Southern delta Aquariids: July 29-30
  • Alpha Capricornids: July 30-31
  • Perseids: Aug. 11-12
  • Orionids: Oct. 20-21
  • Southern Taurids: Nov. 4-5
  • Northern Taurids: Nov. 11-12
  • Leonids: Nov. 17-18
  • Geminids: Dec. 13-14
  • Ursids: Dec. 21-22

If you live in an urban area, you may want to drive to a place that isn’t littered with city lights to get the best view.

Find an open area with a wide view of the sky. Make sure you have a chair or blanket so you can look straight up. And give your eyes about 20 to 30 minutes — without looking at your phone or other electronics — to adjust to the darkness so the meteors will be easier to spot.

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