Connect with us

Published

2 weeks ago

on

After almost seventy years of study, astronomers are still fascinated by active galactic nuclei (AGN), otherwise known as quasi-stellar objects (or “quasars.”) These are the result of supermassive black holes (SMBHs) at the center of massive galaxies, which cause gas and dust to fall in around them and form accretion disks. The material in these disks is accelerated to close to the speed of light, causing it to release tremendous amounts of radiation in the visible, radio, infrared, ultraviolet, gamma-ray, and X-ray wavelengths. In fact, quasars are so bright that they temporarily outshine every star in their host galaxy’s disk combined.

The brightest quasar observed to date, 100,000 billion times as luminous as our Sun, is known as SMSS J114447.77-430859.3 (J1144). This AGN is hosted by a galaxy located roughly 9.6 billion light years from Earth between the constellations Centaurus and Hydra. Using data from the eROSITA All Sky Survey and other space telescopes, an international team of astronomers conducted the first X-ray observations of J1144. This data allowed the team to investigate prevailing theories about AGNs that could provide new insight into the inner workings of quasars and how they affect their host galaxies.

The team was led by Dr. Elias Kammoun, a postdoctoral researcher with the Research Institute in Astrophysics and Planetology (IRAP), and Zsofi Igo, a Ph.D. candidate at the Max Planck Institute for Extraterrestrial Physics (MPE). They were joined by colleagues from the IRAP and MPE and researchers from the Italian National Institute of Astrophysics (INAF), the Leibniz Institute for Astrophysics (AIP), and multiple universities. The paper that describes their findings appeared on April 3rd in the Monthly Notices of the Royal Astronomical Society.

Built by the MPE, eROSITA is the primary instrument on board the Spectrum-Roentgen-Gamma (SRG) – aka. Spektr-RG – a Russian-German space observatory launched in 2019 and currently operating in a halo orbit around the L2 Lagrange point. This observatory was designed to perform the first all-sky survey in the medium energy X-ray wavelength – up to 10 kilo-electronvolts (keV). During its first five sky scans between 2020 and 2022, eROSITA detected J1144 as an X-ray source. However, it was not observed in visible wavelengths until 2022 by the SkyMapper Southern Survey (SMSS).

As they state in their study, most of what is known about AGNs is based on the study of nearby, low-mass, low-accretion quasars. Detailed observations of a high-mass, high-accretion AGN are needed to understand how SMBHs grow over time and how this affects their host galaxy (and several key properties of AGNs). In addition to its brightness, J1144 is much closer to Earth than similarly-luminous sources, making it ideal for astronomers to observe its SMBH and the effects it has on the surrounding environment. As Dr. Kammoun explained in an MPE press release:

“Similar quasars are usually found at much larger distances, so they appear much fainter, and we see them as they were when the Universe was only 2-3 billion years old. J1144 is a very rare source as it is so luminous and much closer to Earth, giving us a unique glimpse of what such powerful quasars look like.”

For their study, Dr. Kammoun and his colleagues combined data from several space telescopes, including the SRG, the ESA XMM-Newton observatory, NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR), and NASA’s Neil Gehrels Swift observatory. This allowed them to test theories about the X-ray properties of a high-mass, high-accretion AGN. This allowed them to measure the temperature of the X-rays being emitted, around 350 million K (~350 million °C; 630 million °F), more than 60,000 times the Sun’s surface temperature.

original1 1
Visualization of a faint X-ray source detected by the eROSITA Final Equatorial-Depth Survey (eFEDS). Credit: MPE/Cluster Origins

These results also allowed them to constrain the mass and growth rate of the central black hole, which they estimate to be 10 billion solar masses, and growing on the order of 100 solar masses per year. Moreover, observations by the eROSITA instrument showed how J1144 has evolved over time, including how its brightness varies over the course of a year but remains relatively consistent in terms of its energy spectrum. These
Did you miss our previous article…
https://mansbrand.com/photo-gallery-hiking-and-backpacking-idahos-sawtooth-mountains-2/

Total
0
Shares
Share 0
Tweet 0
Pin it 0
Share 0
Related Topics:
Continue Reading

Frontier Adventure

The Best Backpacking Gear for the John Muir Trail

Published

10 hours ago

on

June 5, 2023

By

Wind4 016 2

By Michael Lanza

So you’re planning to thru-hike the John Muir Trail and making all of the necessary preparations, and now you’re wondering: What’s the best gear for a JMT hike? Having thru-hiked the JMT as well as taken numerous other backpacking trips all over the High Sierra—mostly between late August and late September, which I consider that the best time to walk the Sierra, to avoid snow and the voracious mosquitoes and blazing hot afternoons of mid-summer—I offer the following picks for the best lightweight backpacking gear and apparel for a JMT thru-hike.

Indisputably one of the best backpacking trips in America—and among the very best I’ve taken over three decades of backpacking, including 10 years I spent as Northwest Editor and lead gear reviewer for Backpacker magazine and even longer running this blog—the JMT meanders for 211 miles through the magnificent High Sierra, from Yosemite Valley to the summit of the highest peak in the Lower 48, 14,505-foot Mount Whitney (where backpackers must then descend another 11 miles to finish the trip at Whitney Portal trailhead). See my story about thru-hiking the JMT in seven days.

With few opportunities to resupply along the trail—and given the generally dry weather in the Sierra in summer—you can easily and should hike the JMT with the lightest gear that works for you (or that you can afford). Maximum pack weight will depend on how many days you spend on the trail and your food weight, but it’s quite feasible to keep your base pack weight (everything but food and water) within 15 pounds or less—and certainly no more than 20 pounds—without compromising safety or comfort in camp.

Wind4 016 3
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-guides to classic backpacking trips. Click here to learn how I can help you plan your next trip.

A backpacker hiking the John Muir Trail above Helen Lake in Kings Canyon N.P., High Sierra.
” data-image-caption=”Marco Garofalo backpacking the John Muir Trail above Helen Lake in Kings Canyon N.P. Click photo to learn how I can help you plan your JMT thru-hike.
” data-medium-file=”https://i0.wp.com/thebigoutside.com/wp-content/uploads/2022/10/JMT2-085-Marco-Garofalo-hiking-above-Helen-Lake-John-Muir-Trail-Kings-Canyon-N.P.-High-Sierra..jpg?fit=300%2C200&ssl=1″ data-large-file=”https://i0.wp.com/thebigoutside.com/wp-content/uploads/2022/10/JMT2-085-Marco-Garofalo-hiking-above-Helen-Lake-John-Muir-Trail-Kings-Canyon-N.P.-High-Sierra..jpg?fit=900%2C600&ssl=1″ decoding=”async” width=”900″ height=”600″ src=”https://i0.wp.com/thebigoutside.com/wp-content/uploads/2022/10/JMT2-085-Marco-Garofalo-hiking-above-Helen-Lake-John-Muir-Trail-Kings-Canyon-N.P.-High-Sierra..jpg?resize=900%2C600&ssl=1″ alt=”A backpacker hiking the John Muir Trail above Helen Lake in Kings Canyon N.P., High Sierra.” class=”wp-image-54840″ srcset=”https://i0.wp.com/thebigoutside.com/wp-content/uploads/2022/10/JMT2-085-Marco-Garofalo-hiking-above-Helen-Lake-John-Muir-Trail-Kings-Canyon-N.P.-High-Sierra..jpg?resize=1024%2C683&ssl=1 1024w, https://i0.wp.com/thebigoutside.com/wp-content/uploads/2022/10/JMT2-085-Marco-Garofalo-hiking-above-Helen-Lake-John-Muir-Trail-Kings-Canyon-N.P.-High-Sierra..jpg?resize=300%2C200&ssl=1 300w, https://i0.wp.com/thebigoutside
Did you miss our previous article…
https://mansbrand.com/crs-28-mission-control-audio/

Continue Reading

Frontier Adventure

CRS-28 Mission Control Audio

Published

12 hours ago

on

June 5, 2023

By

hqdefault 2

hqdefault 3

This is the vehicle trajectory and mission control audio without any additional commentary. There may be very long periods of silence. For our full hosted webcast, visit

Did you miss our previous article…
https://mansbrand.com/photo-gallery-36-gorgeous-backcountry-lakes/

Continue Reading

Frontier Adventure

Photo Gallery: 36 Gorgeous Backcountry Lakes

Published

13 hours ago

on

June 5, 2023

By

Wind4 016

By Michael Lanza

Water makes up about 60 percent of our bodies—and, I suspect, 100 percent of our hearts. We crave it not only physically, for survival, but emotionally, for spiritual rejuvenation. We love playing in it for hours as children and we paddle and swim in it as adults. We’re drawn by the calming effects of sitting beside a stream or lake in a beautiful natural setting, an experience that possesses a certain je ne sais quoi—a quality difficult to describe, but that we can all feel.

And nothing beats taking a swim in a gorgeous backcountry lake.

I’ve come across quite a few wonderful backcountry lakes over more than three decades of exploring wilderness—including about 10 years as the Northwest Editor of Backpacker magazine and even longer running this blog. I’ve just updated and expanded this list of my favorites to give you some eye candy as well as ideas for future adventures—and perhaps compare against your list of favorite backcountry lakes.

Wind4 016 1
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-guides to classic backpacking trips. Click here to learn how I can help you plan your next trip.

Click on the links to my stories in these brief writeups to learn more about each of these trips. Much of this story is free for anyone to read, but reading the entire story requires a paid subscription. See my Custom Trip Planning page to learn how I can help you plan a trip to any of these lakes.

If you know some gorgeous lakes that are not on my list, please suggest them in the comments section below this story. I try to respond to all comments.

Here’s to your next peaceful moment beside a gorgeous lake deep in the mountains somewhere.

Elizabeth Lake in Glacier National Park.
” data-image-caption=”Early morning at Elizabeth Lake in Glacier National Park. Click photo to learn how I can help you plan your Glacier trip.
” data-medium-file=”https://i0.wp.com/thebigoutside.com/wp-content/uploads/2020/03/Gla6-018-Elizabeth-Lake-in-Glacier-National-Park.-2.jpg?fit=300%2C200&ssl=1″ data-large-file=”https://i0.wp.com/thebigoutside.com/wp-content/uploads/2020/03/Gla6-018-Elizabeth-Lake-in-Glacier-National-Park.-2.jpg?fit=900%2C600&ssl=1″ decoding=”async” width=”900″ height=”600″ src=”https://i0.wp.com/thebigoutside.com/wp-content/uploads/2020/03/Gla6-018-Elizabeth-Lake-in-Glacier-National-Park.-2.jpg?resize=900%2C600&ssl=1″ alt=”Elizabeth Lake in Glacier National Park.” class=”wp-image-38774″ srcset=”https://i0.wp.com/thebigoutside.com/wp-content/uploads/2020/03/Gla6-018-Elizabeth-Lake-in-Glacier-National-Park.-2.jpg?resize=1024%2C683&ssl=1 1024w, https://i0.wp.com/thebigoutside.com/wp-content/uploads/2020/03/Gla6-018-Elizabeth-Lake-in-Glacier-National-Park.-2.jpg?resize=300%2C200&ssl=1 300w, https://i0.wp.com/thebigoutside.com/wp-content/uploads/2020/03/Gla6-018-Elizabeth-Lake-in-Glacier-National-Park.-2.jpg?resize=768%2C512&ssl=1 768w, https://i0.wp.com/thebigoutside.com/wp-content/uploads/2020/03/Gla6-018-Elizabeth-Lake-in-Glacier-National-Park.-2.jpg?resize=1080%2C720&ssl=1 1080w, https://i0.wp.com/thebigoutside.com/wp-content/uploads/2020/03/Gla6-018-Elizabeth-Lake-in-Glacier-National-Park.-2.jpg?w=1200&ssl=1 1200w” sizes=”(max-width: 900px) 100vw, 900px” data-recalc-dims=”1″ />Elizabeth Lake in Glacier National Park.

Elizabeth Lake, Glacier National
Did you miss our previous article…
https://mansbrand.com/astronomers-are-searching-for-a-galaxy-wide-transmitter-beacon-at-the-center-of-the-milky-way/

Continue Reading

Trending