Showing posts with label Milky Way. Show all posts
Showing posts with label Milky Way. Show all posts

Friday, December 1

Observing Something Rare


Astronomers have observed a rare instance of a solar system inside the Milky Way whose planets orbit in sync around their host star, according to a study published yesterday. Researchers believe the motion of the planets has remained virtually unchanged since the system's formation roughly 4 billion years ago.

The four closest planets display what is known as 3:2 resonance—for every three orbits a planet makes around the host star, the next farthest planet completes two orbits. The next two planets display a similar 4:3 resonance. Typically, newborn systems are knocked out of balance by some disruptive event (for example, collisions with asteroids). Because the planets in question have maintained their original orbits, their study is expected to shed light on the early stages of star system formation.

The host star is also the brightest discovered to date to have more than four planets orbiting around it. Visualize the motion of the six planets here.

Wednesday, June 14

Light Years In Length


It turns out those stretched-out hyperspace lines from Star Wars are real. Sort of. According to EurekAlert!, a team of astrophysicists has discovered a bunch of one-dimensional filaments between 5-10 light-years in length chilling in the middle of our galaxy, the Milky Way.

While the long white lines that appear when Han Solo throws the hyperspace lever on the Falcon are actually stars, these new filaments are thought to be some kind of outflow from Sagittarius A—a supermassive black hole that lies at the center of the Milky Way. 

Essentially the filaments are exceptionally long strings of electrons interacting with a magnetic field. These new filaments run horizontally and only appear on one side of Sag A, leading scientists to believe they were birthed from the black hole millions of years ago.

That’s right; these “new” one-dimensional space strings aren’t exactly new. Even if we set aside their age, the existence of gigantic one-dimensional filaments in the Milky Way was discovered back in the early ’80s by astrophysicist Farhad Yusef-Zadeh. 

The filaments Yusef-Zadeh discovered, however, were huge vertical monoliths measuring up to 150 light-years high. It’s the horizontal orientation of the new filaments that make them so interesting.

“I’m used to them being vertical,” Yusef-Zadeh confessed in the new paper released by Northwestern University. “I never considered there might be others along the plane.” 

Yusef-Zadeh went on to explain that studying the Milky Way’s filaments could help scientists learn more about the way Sag A spins and its orientation relative to the rest of the Milky Way.

The old vertical filaments first discovered hanging around the Milky Way in 1984 run perpendicular to the galactic plane. The new horizontal filaments, however, are parallel to the plane and point radially toward the black hole at the center of our galaxy. Another difference between the two types of filaments is how they behave.   READ MORE...

Sunday, June 11

Signals From the Milky Way


Could intelligent aliens be lurking at the heart of the Milky Way?

A new search for extraterrestrial life aims to find out by listening for radio pulses from the center of our galaxy. Narrow-frequency pulses are naturally emitted by stars called pulsars, but they're also used deliberately by humans in technology such as radar. 

Because these pulses stand out against the background radio noise of space, they're an effective way of communicating across long distances — and an appealing target to listen for when searching for alien civilizations.

Scientists described the alien-hunting strategy in a new study, published May 30 in The Astronomical Journal. Researchers led by Cornell University graduate student Akshay Suresh developed software to detect these repetitive frequency patterns and tested it on known pulsars to be sure it could pick up the narrow frequencies. 

These frequency ranges are very small, at about a tenth of the width of frequencies used by a typical FM radio station. The researchers then searched data from the Green Bank Telescope in West Virginia using the method.  READ MORE...

Monday, November 14

Behind the Milky Way


A composite image showing the 58 galaxies clustered together in the "zone of avoidance" behind the Milky Way. (Image credit: Galdeano et al. / ESO)




Astronomers have detected an enormous extragalactic structure hiding in an uncharted region of space far beyond the Milky Way's center.


This phantom region, known as the zone of avoidance, is a blank spot on our map of the universe, comprising somewhere between 10% and 20% of the night sky. 

The reason we can't see it — at least with standard visible light telescopes — is because the Milky Way's bulging center blocks our view of it; the center of our galaxy is so dense with stars, dust and other matter that light from the zone of avoidance gets scattered or absorbed before reaching Earth's telescopes.

However, researchers have had better luck uncovering the zone's secrets with telescopes that can detect infrared radiation — a type of energy that's invisible to human eyes, but powerful enough to shine through dense clouds of gas and dust. 

Infrared surveys of the zone of avoidance have found evidence of thousands of individual galaxies shining through the cosmic fog, though little is known about the large-scale structures that lurk there.  READ MORE...

Wednesday, July 13

Pillars of Creation


Photographer Andrew McCarthy recreated NASA’s famous “Pillars of Creation” photograph of the Eagle Nebula using a $500 telescope.

The original iconic image, taken by the Hubble telescope, shows an active star-forming region featuring towering tendrils of cosmic dust and gas in the heart of the Eagle Nebula, cataloged as M16.

It was first photographed in 1995 by NASA and has had a huge cultural impact with the image being featured on everything from “t-shirts to coffee mugs,” reports National Geographic.

A $16B Space Telescope vs a $500 backyard telescope
McCarthy spoke to PetaPixel about how he recreated the Pillars of Creation from his backyard in Arizona with a 12-inch Newtonian telescope and a monochrome camera using narrowband filters to create a vibrant color image.

“I shoot the Pillars of Creation a couple times a year. It’s a surprisingly accessible target, near the Sagittarius star cloud in the core of the Milky Way,” explains McCarthy.

“I used special software to remove all the stars in the image, so this unobstructed view really shows off the vast structures of gas and dust within the Eagle Nebula.

“The image was shot over several hours across multiple nights, while my telescope was guided along the stars using a sophisticated tracking mount that compensated for the earth’s rotation.”  READ MORE...

Friday, June 24

Backyard Photography of Galaxyk


In the summer of 2020, the world was enthralled with the Comet Neowise, which only makes an appearance every 6,800 years. Brennan Gilmore was so enthralled that it kicked off a passion for astrophotography that continues today. 

Two years after beginning his journey photographing the stars, he has accomplished a major goal: photographing the Andromeda galaxy.

Our neighbor in the sky, Andromeda is a spiral galaxy similar to our own Milky Way. Sitting 2.5 million light-years away, it remains a bright spot in the atmosphere and was something that Gilmore first photographed two years ago. 

However, it took him some time to build up the skills and acquire the equipment to achieve an image he was happy with. The final result was well worth the wait, as the image went viral after he posted it online and even ended up in Newsweek.

Gilmore captured the stunning image from his backyard in Charlottesville, Virginia, over the course of several nights. Using a four-inch telescope and astronomy camera, he took hundreds of photos of Andromeda. 

From there, he carefully culled his images, using only the very best for the final photograph.

In the end, all of his efforts paid off. The final photo, created from 290 individual frames, is incredibly detailed. Many of Andromeda's one trillion stars are visible through its gas halo. 

Gilmore thought of every detail, including the exposure so that even the core of the galaxy isn't overexposed. This allows viewers to drink in the stars and ponder on this far away neighbor, which is actually headed toward our own galaxyREAD MORE...

Tuesday, May 24

Fusion Rocket Breakthrough

Richard Dinan is the visionary entrepreneur who wants to help humans leave Earth and inhabit other planets in the Milky Way. And he wants to do it fast. His company, Pulsar Fusion, is betting on harnessing the power of nuclear in space to cut the time it takes to get to Mars in half – and unlock the secrets beyond our Solar System.

Speaking exclusively to Science Digest, the former Made In Chelsea star, 35, said: "In the Milky Way there are believed to be billions of habitable planets orbiting G-type stars like ours.

"That doesn't mean that they've got people on them, but it means that they could support life.

"We're living in a world now where maybe the entrepreneurs of the future can own their own planets.  "To do that, they will need very, very fast rockets.

That may sound like a ludicrous thing to say, but we are almost there - Mars has got quite a keen interest.

"I think part of being human is to leave our planet – we've always followed the stars since prehistoric times and now we need to emulate that."

To make this possible, Mr Dinan wants to replicate the fusion process used by stars like our Sun.  Tipped as the "holy grail" energy source, nuclear fusion has been studied for over a century.

Unlike nuclear fission – the powerful reaction that led to the creation of nuclear weapons – fusion takes two light atomic nuclei to combine to form a single heavier one while releasing massive amounts of energy.  READ MORE...

Saturday, April 23

Rare Ring Galaxies


Almost every galaxy can be classified as a spiral, elliptical, or irregular galaxy. Only 1-in-10,000 galaxies fall into the rarest category of all: ring galaxies.  With a dense core consisting of old stars, and a circular or elliptical ring consisting of bright, blue, young stars, the first ring was only discovered in 1950: Hoag's object.  After decades of wondering how these objects form, we've seen enough of them, capturing them in various stages of evolution, that we finally know where they come from.


When we look out into deep space, beyond the confines of the Milky Way, we find that the Universe isn’t quite so empty. Galaxies — small and large, near and far, in rich clusters and in near-total isolation — fill the abyss of space, with the Milky Way being just one of approximately two trillion such galaxies within the observable Universe. 


Galaxies are collections of normal matter, including plasmas, gas, dust, planets, and most prominently, stars. It’s through the examination of that starlight that we’ve learned the most about the physical properties of galaxies, and been able to reconstruct how they came to be.


In general, there are four classes of galaxies that we see. Spirals, like the Milky Way, are the most common type of large galaxy in the Universe. Ellipticals, like M87, are the largest and most common type of galaxy in the rich, central regions of galaxy clusters. Irregular galaxies are a third ubiquitous type, usually distorted from a prior spiral or elliptical shape by gravitational interactions. 


But there’s a very rare type that’s striking and beautiful: ring galaxies. They make up only 1-in-10,000 of all the galaxies out there, with the first one, Hoag’s object, only discovered in 1950. After more than 70 years, we’ve finally figured out how the Universe makes them.  READ MORE...

Monday, March 21

How Fast are we Moving?


No matter what perspective you choose to look at it from, planet Earth is always in motion. Our planet rotates on its axis continuously, spinning and completing a full 360° rotation approximately once a day. As we spin, we also revolve around the Sun, completing a nearly 1 billion kilometer journey every single year. Moreover, the entire Solar System — Sun, planets, moons, and all — moves through the Milky Way galaxy, orbiting around the galactic center on timescales far greater than humanity has existed for. And finally, the Milky Way galaxy moves within the Local Group, which itself moves through intergalactic space.


Depending on what we’re measuring our motion relative to, we can quantify just how quickly planet Earth moves through the Universe. Even though our motion is barely detectable through the experiments we can perform here on Earth, a look out at the Universe enables us to understand precisely how we’re in motion on each and every scale. Here’s how we know what our cosmic motion is, from each individual component to the entire cumulative effects of everything combined.


This view of the Earth comes to us courtesy of NASA’s MESSENGER spacecraft, which had to perform flybys of Earth and Venus in order to lose enough energy to reach its ultimate destination: Mercury. The round, rotating Earth and its features are undeniable, as this rotation explains why Earth bulges at the center, is compressed at the poles, and has different equatorial and polar diameters.(Credit: NASA/MESSENGER)



How fast does the Earth spin?
This question, although it might seem simple, has a different answer dependent on where, precisely, you are on the planet’s surface. Planet Earth is a rigid body, meaning that the land masses remain relatively constant with respect to one another over time. As the Earth rotates about its axis, practically every point on the surface completes a full rotation in just under 24 hours: 23 hours, 56 minutes, and 4.09 seconds, to be precise.  READ MORE...

Tuesday, March 8

A Spectacular Universe


Just 12 million light-years away, the galaxies Messier 81 and 82 offer a nearby preview of the Milky Way-Andromeda merger.


Right in our cosmic backyard, a preview of the Milky Way’s future unfolds.
The galaxy Messier 81, also known as Bode’s Galaxy, is one of the brightest and closest galaxies to Earth not found in our Local Group. By connectng the lower-left corner of the Big Dipper’s cup to the upper-right corner and then traveling that same distance in the same direction, you can find M81 and the other major galaxies of its group all clustered together. (Credit: E. Siegel/Stellarium)

Just outside the Big Dipper’s “cup,” Bode’s Galaxy, Messier 81, lingers.
This optical image of Bode’s Galaxy, M81, comes courtesy of the Hubble Space Telescope. The spiral arms are littered with hot, young, blue stars, while large extent of the arms indicates a gravitational interaction with one or more nearby neighbors. A wider-field and multiwavelength view supports that. (Credit: NASA, ESA and the Hubble Heritage Team (STScI/AURA))

12 million light-years away, it’s a naked eye object for those with acute vision and exceptionally dark skies.
The two largest, brightest galaxies in the M81 Group, M81 (right) and M82 (left), are shown in the same frame in these 2013 and 2014 photos. In 2014, M82 experienced a supernova, visible in the 2014 (blue) image just above the galactic center. (Credit: Simon in the Lakes)

The largest galaxy in the M81 group moves ever-so-slightly towards us.       READ MORE...

Wednesday, January 26

Radio Signals From Milky Way

The radio telescope at the Parkes Observatory at sunset near the town of Parkes, Australia, July 15, 2019.  Stefica Nicol Bikes/Reuters



Mysterious radio waves emanating from the center of the galaxy have astronomers stumped.
Four objects have briefly emitted radio signals that don't resemble any known type of star.
Scientists think each of the four signals could come from a new type of object unknown to astronomy.

Ziteng Wang found a needle in an astronomical haystack.

Wang, a physics PhD student at the University of Sydney, was combing through data from Australia's ASKAP radio telescope in late 2020. His research team had detected 2 million objects with the telescope and was classifying each one.

The computer identified most of the stars, and the stage of life or death they were in. It picked out telltale signs of a pulsar (a rapidly rotating dead star), for example, or a supernova explosion. But one object in the center of our galaxy stumped the computer and the researchers.

The object emitted powerful radio waves throughout 2020 — six signals over nine months. Its irregular pattern and polarized radio emissions didn't look like anything the researchers had seen before.

Even stranger, they couldn't find the object in X-ray, visible, or infrared light. They lost the radio signal, too, despite listening for months with two different radio telescopes.

It reappeared suddenly, about a year after they first detected it, but within a day, it was gone again.  READ MORE...

Monday, January 24

Filaments of Hydrogen


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).  READ MORE...

Saturday, January 15

Swiss Cheese Bubble Created by Supernovas

 

Artist's illustration of the Local Bubble with the sun's location in the center and star formation occurring on the bubble's surface. (Image credit: Leah Hustak (STScI))


In the new study, published online Jan. 12 in the journal Nature, researchers accurately mapped the star-forming regions surrounding the Local Bubble and, in doing so, calculated how fast the superbubble is expanding. 
This allowed the team to work out exactly how many supernovas were needed to carve out the gigantic cosmic void and better understand how star-forming regions are created across the Milky Way.Earth is slap bang in the middle of a 1,000 light-year-wide bubble with a dense surface birthing thousands of baby stars. Researchers have long wondered what created this "superbubble." Now, a new study suggests that at least 15 powerful star explosions inflated this cosmic bubble.

Astronomers in the 1970s first discovered the gigantic void, known as the Local Bubble, after realizing that no stars had formed inside the blob for around 14 million years. The only stars inside the bubble either existed before the bubble emerged or formed outside the void and are now passing through; the sun is one such trespasser. 
This setup had suggested that several supernovas were responsible for this void. Those stellar explosions, the researchers said, would have blasted the materials needed to make new stars, such as hydrogen gas, to the edge of a huge area in space, leaving behind the Local Bubble that's surrounded by a frenzy of star births.  READ MORE...

Monday, August 16

Milky Way Streaking

In 2017, astronomers noticed a star streaking out of the Milky Way at nearly 2 million mph (3.2 million km/h) — roughly four times faster than our sun orbits — and flying against the direction in which most stars trek around the galactic center. 

It's also made of completely different star stuff, mostly heavy, "metallic" atoms rather than the usual light elements. 

LP 40-365, as it was called, was as eye-catching as a wooden car barreling up the interstate against traffic at hundreds of miles per hour.

"It is exceptionally weird in a lot of different ways," said study lead author J.J. Hermes, an astronomer at Boston University.

The star moves so quickly that it's headed out of our galaxy for good, which astronomers have taken as evidence that the metallic explorer was launched here by a cosmic catastrophe — a supernova. 

But they couldn't tell how the supernova had sent it flying. Was LP 40-365 a piece of the exploded star itself? Or was it a partner star flung clear by the shockwave associated with star explosions? 

A new analysis of old data finds that the star — called a white dwarf — spins about its axis at a leisurely pace — a hint that it is indeed a piece of stellar debris (not a partner star) that managed to survive one of the galaxy's most violent and mysterious events.

"We can now connect this star to the shrapnel from an exploded white dwarf with a lot more confidence," said Hermes.  READ MORE

Saturday, July 10

Strange Signals

On April 28, 2020, two ground-based radio telescopes detected an intense pulse of radio waves. It only lasted a mere millisecond but, for astonished astronomers, it was a major discovery, representing the first time a fast radio burst (FRB) had ever been detected so close to Earth.

Located just 30,000 light-years from our planet, the event was firmly within the Milky Way, and it was, to all intents and purposes, almost impossible to miss. The Canadian Hydrogen Intensity Mapping Experiment (CHIME) and the Survey for Transient Astronomical Radio Emission 2 (STARE2) certainly had no problems picking it up. 

"CHIME wasn’t even looking in the right direction and we still saw it loud and clear in our peripheral vision," said Kiyoshi Masui, assistant professor of physics at the Massachusetts Institute of Technology. "STARE2 also saw it, and it’s only a set of a few radio antennae literally made out of cake pans."

Until that point, all FRBs had been observed outside our galaxy. "They’ve been billions of light years away, making them a lot harder to study," said doctoral candidate in physics Pragya Chawla from McGill University in Canada. 

April 2020’s discovery was also notable for being the most energetic radio blast that astronomers have ever recorded in the Milky Way, but what made it most exciting is that scientists are now closer to determining the origin of FRBs than at any point since they were first discovered.  TO READ MORE, CLICK HERE...

Friday, April 23

A Dying Galaxy

From the smallest microbe to the mightiest oak, death is as true for above as it is for below, even for the mightiest galaxies.

The process, however, is not a quick one. A haunting new Hubble photo of the galaxy NGC 1947 demonstrates this well: Even from a distance of around 45.4 million light-years away (in the southern constellation of Dorado), we can see that the galaxy is slowly on the decline.

The clue lies in the dust and gas. A galaxy in the prime of its life will be filled with the stuff, using it to make new stars. Eventually, the star-stuff will run out, and that's what astronomers believe we are seeing with NGC 1947.

It's a rare type of galaxy known as a lenticular galaxy - disk-shaped, like the Milky Way or Andromeda, but without the spiral arms. NGC 1947 used to have spiral arms, but it has used up almost all the gas and dust that gave them structure; all that remains is a few wisps, backlit by starlight.  Read More