Astronomers Find the Biggest Structure in the Milky Way, a Filament of Hydrogen 1,600 Light-Years Long
Roughly 13.8 billion years ago, our Universe was born in a massive explosion that gave rise to the first subatomic particles and the laws of physics as we know them. About 370,000 years later, hydrogen had formed, the building block of stars, which fuse hydrogen and helium in their interiors to create all the heavier elements. While hydrogen remains the most pervasive element in the Universe, it can be difficult to detect individual clouds of hydrogen gas in the interstellar medium (ISM).
This makes it difficult to research the early phases of star formation, which would offer clues about the evolution of galaxies and the cosmos. An international team led by astronomers from the Max Planck Institute of Astronomy (MPIA) recently noticed a massive filament of atomic hydrogen gas in our galaxy. This structure, named “Maggie,” is located about 55,000 light-years away (on the other side of the Milky Way) and is one of the longest structures ever observed in our galaxy.
The study that describes their findings, which recently appeared in the journal Astronomy & Astrophysics, was led by Jonas Syed, a Ph.D. student at the MPIA. He was joined by researchers from the University of Vienna, the Harvard-Smithsonian Center for Astrophysics (CfA), the Max Planck Institute for Radio Astronomy (MPIFR), the University of Calgary, the Universität Heidelberg, the Centre for Astrophysics and Planetary Science, the Argelander-Institute for Astronomy, the Indian Institute of Science, and NASA’s Jet Propulsion Laboratory (JPL).
The research is based on data obtained by the HI/OH/Recombination line survey of the Milky Way (THOR), an observation program that relies on the Karl G. Jansky Very Large Array (VLA) in New Mexico. Using the VLA’s centimeter-wave radio dishes, this project studies molecular cloud formation, the conversion of atomic to molecular hydrogen, the galaxy’s magnetic field, and other questions related to the ISM and star formation.
The ultimate purpose is to determine how the two most-common hydrogen isotopes converge to create dense clouds that rise to new stars. The isotopes include atomic hydrogen (H), composed of one proton, one electron, and no neutrons, and molecular hydrogen (H2) – or Deuterium – is composed of one proton, one neutron, and one electron. Only the latter condenses into relatively compact clouds that will develop frosty regions where new stars eventually emerge.
The process of how atomic hydrogen transitions to molecular hydrogen is still largely unknown, which made this extraordinarily long filament an especially exciting find. Whereas the largest known clouds of molecular gas typically measure around 800 light-years in length, Maggie measures 3,900 light-years long and 130 light-years wide. As Syed explained in a recent MPIA press release:
“The location of this filament has contributed to this successWe don’t yet know exactly how it got there. But the filament extends about 1600 light-years below the Milky Way plane.The observations also allowed us to determine the velocity of the hydrogen gasThis allowed us to show that the velocities along the filament barely differ.”
The section of the Milky Way, as measured by ESA’s Gaia satellite (top). The box marks the location of the “Maggie” filament and the false-color image of atomic hydrogen distribution (bottom), the red line indicating the “Maggie” filament. Credit: ESA/Gaia/DPAC/T. Müller/J. Syed/MPIA
The team’s analysis showed that matter in the filament had a mean velocity of 54 km/s-1, which they determined mainly by measuring it against the rotation of the Milky Way disk. This meant that radiation at a wavelength of 21 cm (aka. the “hydrogen line“) was visible against the cosmic background, making the structure discernible. “The observations also allowed us to determine the velocity of the hydrogen gas,” said Henrik Beuther, the head of THOR and a co-author on the study. “This allowed us to show that the velocities along the filament barely differ.”
From this, the researchers concluded that Maggie is a
Did you miss our previous article…
The Kuiper Belt is Much Bigger Than We Thought
NASA’s New Horizons spacecraft is just over 8.8 billion km away, exploring the Kuiper Belt. This icy belt surrounds the Sun but it seems to have a surprise up its sleeve. It was expected that New Horizons would be leaving the region by now but it seems that it has detected elevated levels of dust that are thought to be from micrometeorite impacts within the belt. It suggests perhaps that the Kuiper Belt may stretch further from the Sun than we thought!
The Kuiper Belt is found beyond the orbit of Neptune and is thought to extend out to around 8 billion km. Its existence was first proposed in the mid-20th century by Gerard Kuiper after whom the belt has been named. It’s home to numerous icy bodies and dwarf planets and offers valuable insight into the formation and evolution of the Solar System.
Launched by NASA in January 2006 atop an Atlas V rocket, the New Horizon’s spacecraft embarked on its mission to explore the outer Solar System. The primary objective was to perform a close flyby of Pluto, which it did 9.5 years after it launched, and continue on to explore the Kuiper Belt.
New Horizons completed its flyby of Pluto in 2015, and has been travelling through the Kuiper Belt since. As it travels through the outer reachers of the region, almost 60 times the distance from Earth to the Sun, its Venetia Burney Student Dust Counter (SDC) has been counting dust levels. The instrument was constructed by students at the Laboratory for Atmospheric Space Physics at the University of Colorado Boulder. Throughout New Horizon’s journey, SDC has been monitoring dust levels giving fabulous insight into collision rates among objects in the outer Solar System.
The New Horizons instrument payload that is currently doing planetary science, heliospheric measurements, and astrophysical observations. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
The dust particle detections announced in a recent paper published in the Astrophysical Journal Letters by lead author Alex Doner are thought to be frozen remains from collisions between larger Kuiper Belt Objects (KBOs). The results were a real surprise and challenged the existing models that predicted a decline in dust density and KBO population. It seems that the belt extends many billions of miles beyond the current estimates or maybe even that there is a second belt!
The results came from data gathered over a three year period during New Horizon’s journey from 45 to 55 astronomical units (where 1 astronomical unit is the average distance between the Sun and Earth). While New Horizon’s was gathering data about dust, observatories such as the 8.2-meter optical-infrared Subaru Telescope in Hawaii have been making discoveries of new KBOs. Together these findings suggest the Kuiper Belt objects and dust may well extend a further 30 AUs out to about 80 AUs from the Sun.
New Horizons is now in its extended mission and hopefully has sufficient power and propellant to continue well into the 2040s. At its current velocity that will take the spacecraft out to about 100 AU from the Sun so the research team speculate that the SDC could identify the transition point into interstellar space.
Source : NASA’s New Horizons Detects Dusty Hints of Extended Kuiper Belt
The post The Kuiper Belt is Much Bigger Than We Thought appeared first on Universe Today.
Did you miss our previous article…
A Planetary Disk in the Orion Nebula is Destroying and Replenishing Oceans of Water Every Month
Planet-forming disks are places of chaotic activity. Not only do planetesimals slam together to form larger worlds, but it now appears that the process involves the destructive recycling of water within a disk. That’s the conclusion from scientists studying JWST data from a planetary birth crèche called d203-506 in the Orion Nebula.
The data they studied suggest that an amount of water equivalent to all of Earth’s oceans is created and replenished in a relatively short period—about a month. According to study co-lead Els Peeters at Western University in Canada, it was relatively easy to discover this process in the protoplanetary disk. “This discovery was based on a tiny fraction of our spectroscopic data,” she said. “It is exciting that we have so much more data to mine and I can’t wait to see what else we can find.”
The Orion Nebula is a vast active star- and planet-forming region and the d203-506 protoplanetary disk lies within it at a distance of about 1,350 light-years away from Earth. Astronomers study the nebula to understand all aspects of star birth since there are so many newborn stars there. In addition, many are surrounded by disks of gas and dust, called protoplanetary disks (proplyds, for short). Those regions are excellent places to observe planet-formation processes, and particularly the interplay between the young stars and their disks.
The Orion Nebula is one of the most studied objects in the sky. Many of its protostars and their planetary disks likely contain water in some form. Image: NASA
The Water Cycle of a Proplyd
We all know that water is an important ingredient for life. It certainly played a role in creating and sustaining life on our planet. As it turns out, water is a significant fraction of the materials in a proplyd. In the infant Solar System, water existed throughout our proplyd long before any of the planets formed, largely in their icy form, either as icy bodies or locked into asteroids and planetesimals. It also exists in interstellar space.
This view of Earth’s horizon by an Expedition 7 crewmember onboard the International Space Station. A new study suggests that Earth’s water didn’t all come from comets, but likely also came from water-rich planetesimals. Credit: NASA
Most of Earth’s water got delivered to the forming planet over millions of years. It melted or outgassed to form the oceans, rivers, and lakes we see today. But, some fraction of the water in our system’s birth disk probably went through a “freeze-thaw” cycle within the disk. That happened when the Solar System was still just a disk of gas and dust. The water was essentially destroyed and then re-formed at higher temperatures.
We can’t see that effect anymore in our system. But, astronomers can point telescopes at other proplyds to see if the same process happens there. That’s what Peeters and her team did. They used JWST to look at d203-506. There, bright young stars flood the nearby regions in the proplyd with intense ultraviolet radiation. The UV breaks up water molecules to form hydroxyl molecules and that process also releases infrared light. JWST can search out that light and report back on how much hydroxyl
Did you miss our previous article…
The 12 Best Hikes in Utah’s National Parks
By Michael Lanza
From natural arches, hoodoos, and hanging gardens to balanced rocks and towering mesas, slot canyons and vast chasms, the desert Southwest holds in its dry, searing, lonely open spaces some of America’s most fascinating and inspiring geology. The writer “Cactus Ed” Abbey no doubt had this region in mind when he said there “are some places so beautiful they can make a grown man break down and weep.” Much of it sits protected within southern Utah’s five national parks: Zion, Bryce Canyon, Arches, Canyonlands, and Capitol Reef.
The good news? Many of the best sights can be reached on dayhikes of anywhere from a couple hours to a full day.
A hiker below the Wall of Windows on the Peek-a-Boo Loop in Bryce Canyon National Park.
” data-image-caption=”Cyndi Hayes hiking below the Wall of Windows on the Peek-a-Boo Loop in Bryce Canyon National Park.
” data-medium-file=”https://i0.wp.com/thebigoutside.com/wp-content/uploads/2020/02/Bryce2-013-Wall-of-Windows-Peek-a-Boo-loop-Bryce-Canyon-UT.jpg?fit=300%2C199&ssl=1″ data-large-file=”https://i0.wp.com/thebigoutside.com/wp-content/uploads/2020/02/Bryce2-013-Wall-of-Windows-Peek-a-Boo-loop-Bryce-Canyon-UT.jpg?fit=900%2C598&ssl=1″ src=”https://i0.wp.com/thebigoutside.com/wp-content/uploads/2020/02/Bryce2-013-Wall-of-Windows-Peek-a-Boo-loop-Bryce-Canyon-UT.jpg?resize=900%2C598&ssl=1″ alt=”A hiker below the Wall of Windows on the Peek-a-Boo Loop in Bryce Canyon National Park.” class=”wp-image-43917″ srcset=”https://i0.wp.com/thebigoutside.com/wp-content/uploads/2020/02/Bryce2-013-Wall-of-Windows-Peek-a-Boo-loop-Bryce-Canyon-UT.jpg?resize=1024%2C680&ssl=1 1024w, https://i0.wp.com/thebigoutside.com/wp-content/uploads/2020/02/Bryce2-013-Wall-of-Windows-Peek-a-Boo-loop-Bryce-Canyon-UT.jpg?resize=300%2C199&ssl=1 300w, https://i0.wp.com/thebigoutside.com/wp-content/uploads/2020/02/Bryce2-013-Wall-of-Windows-Peek-a-Boo-loop-Bryce-Canyon-UT.jpg?resize=768%2C510&ssl=1 768w, https://i0.wp.com/thebigoutside.com/wp-content/uploads/2020/02/Bryce2-013-Wall-of-Windows-Peek-a-Boo-loop-Bryce-Canyon-UT.jpg?w=1200&ssl=1 1200w” sizes=”(max-width: 900px) 100vw, 900px” data-recalc-dims=”1″ />Cyndi Hayes hiking below the Wall of Windows on the Peek-a-Boo Loop in Bryce Canyon National Park.
Hi, I’m Michael Lanza, creator of The Big Outside. Click here to sign up for my FREE email newsletter. Join The Big Outside to get full access to all of my blog’s stories. Click here for my e-books to classic backpacking trips. Click here to learn how I can help you plan your next trip.
The list below of the best dayhikes in southern Utah’s national parks derives from numerous trips I’ve made to each of these parks over the past three decades, including the 10 years I spent as a field editor for Backpacker magazine and even longer running this blog. Use my list as your compass, and I guarantee you will knock off the best hikes in these parks.
I’d love to read your thoughts about my list—and your suggestions for dayhikes that belong on it. Please share them in the comments section at the bottom of this story. I try to respond to all comments, and as I continue to explore more trails, I will regularly update this story.
A teenage boy hiking Angels Landing, Zion National Park.
” data-image-caption=”My son, Nate, hiking Angels Landing in Zion National Park.
” data-medium-file=”https://i0.wp.com/thebigoutside.com/wp-content/uploads/2019/09/Zion5-015-Angels-Landing-Zion-National-Park.-copy.-copy.jpg?fit=300%2C200&ssl=1″ data-large-file=”https://i0.wp.com/thebigoutside.com/wp-content/uploads/2019/09/Zion5-015-Angels-Landing-Zion-National-Park.-copy.-copy.jpg?fit=900%2C600&ssl=1″ src=”https://i0.wp.com/thebigoutside.com/wp-content/uploads/2019/09/Zion5-015-Angels-Landing-Zion-National-Park.-copy.-copy.jpg?resize=900%2C600&ssl=1″ alt=”A teenage boy hiking Angels Landing, Zion National Park.” class=”wp-image-35512″ srcset=”https://i0.wp
Did you miss our previous article…
Sports7 days ago
Taylor Swift And Travis Kelce Both Won People’s Choice Awards, As Did Ice Spice, Beyoncé, And Other Music Stars
Tech7 days ago
The Download: missions to Jupiter’s moon Europa, and Uruguay’s screwworm gene drive
Motor6 days ago
ROAD TRIP TO COOLSVILLE: Cars From the 1950s Represent an Incredible Automotive Era in America
Motor7 days ago
Legendary Rock Band Night Ranger to Open for Foreigner, Performing Live at Barrett-Jackson’s “Rock the Block” Concert Presented by Arizona Lottery, January 19
Tech7 days ago
The search for extraterrestrial life is targeting Jupiter’s icy moon Europa
Frontier Adventure7 days ago
How to Get a Permit to Backpack Rainier’s Wonderland Trail
Travel7 days ago
Discover Marrakech: A Treasure Trove of Activities and Attractions
Tech6 days ago
The Download: hunting for new matter, and Gary Marcus’ AI critiques