New Way to Measure Dark Energy

Researchers have discovered a method to potentially detect and measure dark energy by examining the motion between the Milky Way and Andromeda galaxies. This technique, still in its early stages, can estimate the upper value of the cosmological constant, a simple model of dark energy, which is five times higher than values determined from the early universe.




Researchers from the University of Cambridge have discovered a new way to measure dark energy – the mysterious force that makes up more than two-thirds of the universe and is responsible for its accelerating expansion – in our own cosmic backyard.

The researchers found that it may be possible to detect and measure dark energy by studying Andromeda, our galactic next-door neighbor that is on a slow-motion collision course with the Milky Way.


Since it was first identified in the late 1990s, scientists have used very distant galaxies to study dark energy but have yet to directly detect it. 

However, the Cambridge researchers found that by studying how Andromeda and the Milky Way are moving toward each other given their collective mass, they could place an upper limit on the value of the cosmological constant, which is the simplest model of dark energy. 

The upper limit they found is five times higher than the value of the cosmological constant that can be detected from the early universe.

Although the technique is still early in its development, the researchers say that it could be possible to detect dark energy by studying our own cosmic neighborhood. The results are reported in The Astrophysical Journal Letters.

Everything we can see in our world and in the skies – from tiny insects to massive galaxies – makes up just five percent of the observable universe. 

The rest is dark: scientists believe that about 27% of the universe is made of dark matter, which holds objects together, while 68% is dark energy, which pushes objects apart.  READ MORE...

A Rogue Star & Our Solar System

In 1687, Sir Isaac Newton published his magnum opus, Philosophiæ Naturalis Principia Mathematica, which effectively synthesized his theories on motion, velocity, and universal gravitation.

In terms of the latter, Newton offered a means for calculating the force of gravity and predicting the orbits of the planets. Since then, astronomers have discovered that the Solar System is merely one small point of light that orbits the center of the Milky Way Galaxy. On occasion, other stars will pass close to the Solar System, which can cause a dramatic shakeup that can kick objects out of their orbits

These “stellar flybys” are common and play an important role in the long-term evolution of planetary systems. As a result, the long-term stability of the Solar System has been the subject of scientific investigation for centuries. 

According to a new study by a team of Canadian astrophysicists, residents of the Solar System may rest easy. After conducting a series of simulations, they determined that a star will not pass by and perturb our Solar System for another 100 billion years. Beyond that, the possibilities are somewhat frightening!

The research was led by Garett Brown, a graduate student of computational physics from the Department of Physical and Environmental Sciences (PES) at the University of Toronto at Scarborough. He was joined by Hanno Rein, an associate professor of astrophysics (and Brown’s mentor) also from the PES at UT Scarborough. 

The paper that describes their findings was recently published in the Monthly Notices of the Royal Astronomical Journal. As they indicated in their paper, the study of stellar flybys could reveal much about the history and evolution of planetary systems.  READ MORE...

Galactic History

Scientists have found a strange "break" in the spiral arms our Milky Way galaxy that could tell us more about its galactic history.

The grouping of young stars and gassy regions is described by NASA's Jet Propulsion Laboratory (JPL) as looking like "a splinter poking out from a plank of wood" from the plane of the spiral Milky Way's arms.

Finding the feature was a feat in itself, because Earth is inside the Milky Way. In a statement, JPL officials said the difficulty of performing such research is somewhat like standing in Times Square while trying to draw a map of the island of Manhattan.

Researchers tracked the feature down using the infrared or heat-seeking eyes of NASA's Spitzer Space Telescope (before the observatory retired in January 2020) and the European Space Agency's Gaia mission, which measures stellar distances and motions. Gaia's latest major data release was in July.

The new study focused on a nearby region of one of the Milky Way's arms, called the Sagittarius Arm — home of the famous "Pillars of Creation" stacks of stars that form part of the Eagle Nebula (Messier 16.) Between Spitzer and Gaia, the combined data showed Sagittarius is full of young stars that move in space, at nearly the same velocity and direction.  READ MORE

A Lurking Cosmic Cloud

In the yawning vacuum of intergalactic space, something large is lurking.

Not a galaxy, although it's of a comparable size: A vast cloud of hot, faintly glowing gas, bigger than the Milky Way, in the space between galaxies congregating in a huge cluster.

Scientists believe this cloud may have been unceremoniously stripped from a galaxy in the cluster, the first gas cloud of this kind we've ever seen. Even more surprisingly, it hasn't dissipated, but has remained clumped together for hundreds of millions of years.

This not only tells us something new about the environments inside galaxy clusters, it suggests a new way to explore and understand these colossal structures.

"This is an exciting and also a surprising discovery. It demonstrates that new surprises are always out there in astronomy, as the oldest of the natural sciences," said physicist Ming Sun of the University of Alabama in Huntsville.

Galaxy clusters are, as the name suggests, groups of galaxies that are bound together gravitationally. The galaxy cluster where our 'orphan' gas cloud was found is called Abell 1367, or the Leo Cluster, around 300 million light-years away. It contains at least 72 major galaxies, and makes up part of a larger, supercluster complex.

Such environments often have a lot going on, and astronomers like to peer into them to try and figure out how our Universe is connected. In 2017, astronomers using Japan's Subaru Telescope spotted what appeared to be a small, warm cloud in Abell 1367; since its origin was unclear, they went back with more instruments to take a closer look.  TO READ ENTIRE ARTICLE, CLICK HERE...

It's All Relative... I Suppose...

 BIRTH...  DEATH...  INFINITY

BEGINNINGS AND ENDINGS

THE PURPOSE OF THE ENORMITY OF THE UNIVERSE

Relativity -  The absence of standards of absolute and universal application...  and from the area of physics, the dependence of various physical phenomena on relative motion of the observer and the observed objects, especially regarding the nature and behavior of light, space, time, and gravity...

Well...  there you have it...

Everything in this lifetime is relative...

• Politics
• Wars
• Crime
• Ownership
• Thoughts and Feelings
• Understandings
• Knowledge
• Application

But, in all of this wisdom lies a tiny misconception in that it is not logical at all relative to our planet earth and that is the purpose of the universe...  its size...  and the relative fact that it is expanding and into what we know not but can only speculate since our knowledge is limited and only relative at best.

For EXAMPLE...  there are more stars in the universe than there are grains of sand here on EARTH...  and while that statement seems very profound indeed, it still does not explain why our UNIVERSE NEEDS TO BE SOOOO  BIG...

Relatively speaking things are out of proportion when it comes to planet earth and the universe or our solar system and the universe or even our Milky Way Galaxy and the universe when it comes to any kind of comparison.

And...  well into the future of the existence of our universe, I suppose there will be space travel as well as time travel and beings can move back and forth at their leisure and for whatever relative reasons and purposes that they might have...  but it still does not explain what this damn universe has to be so big, relatively speaking that is to say or ask.