To determine the true shape of our galaxy is a complex task.
The Milky Way keeps challenging astronomers who now say that some of our galaxy's spiral arms are straight rather than curved.
New research suggests that the shape of our galaxy is different than previously thought!
The reason why is so difficult to see the structure of our galaxy is because we cannot observe it from the outside, like we see for example our
neighbor Andromeda and other nearby galaxies.
We see the Milky Way edge on, so that nearer stars and clouds are superimposed on more distant ones.
This creates a confusing optical illusion, a real problem astronomers must somehow solve.
When scientists have troubles to determine the distances between the stars, they cannot easily observe the shape of our galaxy's arms, and its overall appearance.
The conventional procedure to determine the shape of the galaxy is a two step process.
First, astronomers must create a model of the galaxy so they can study how each part of it moves in respect to Earth.
Then they need to find cosmic clouds of ionized hydrogen.
By studying the emission spectra and looking for the tell tile shifts in spectral lines that movement causes, astronomers can determine the velocity of the clouds.
By matching this measured velocity to the calculated values, astronomers can work out where in the galaxy any cloud should be.
Unfortunately, this method is far from perfect. Scientists often get unclear results and so far, no-one has been able
to determine how fast the Milky Way rotates.
One of the first maps of the spiral arms based on star formations was published Georgelin & Georgelin in 1976.
Since then many have been devoted to the subject of the Milkly Way's structure. Several attempts have been made to determine the shape of our galaxy.
The Pinwheel galaxy is located 27 million light-years away in the constellation Ursa Major.
Jaques Lepine at the University of Sao Paulo in Brazil and his colleagues have now presented a new intriguing theory.
Instead of studying clouds of ionized hydrogen, the researchers focused their attention on the spectra produced by
clouds of carbon monosulphide, which are relatively common component of our galaxy.
This gave them velocity information for 870 regions of the Milky Way which they have used to create a new map of the galaxy with details never seen before.
Lepine and his colleagues concluded that the Milky Way has an additional spiral arm that was not seen in previous
surveys of the galaxy. The new arm is about 30,000 light years from the galactic core at a longitude of between 80 and 140 degrees.
In addition, Lepine also surprised many when he stated that some of the arms in the Milky Way are not curved in the
traditional way, but are straight instead. This gives the Milky Way a distinctly squarish appearance.
Do we live in a squared galaxy? It is still too early to say, but if true, it would not be the first squared-shaped galaxy.
Astronomers know of many galaxies with straight arms, such as for example M101, the Pinwheel Galaxy, which is nearly twice the size of Milky Way.
Mysteries Of The Sun Explained In Video
Are you curious about the Sun? You now have an excellent chance to learn everything you ever wanted, and even more about our Sun and all its mysteries.
Five new videos called "Mysteries of the Sun" have been just released by NASA.
The videos describe the science of the sun and its effects on the solar system and Earth.
Big Bang Machine Discovers Unknown Particle
Physicists at Cern have not yet been able to confirm the existence of
the elusive "God particle", but they have nevertheless made another interesting discovery
Scientists announced that the Large Hadron Collider, often referred to as the Big Bang machine has detected an unknown particle composed of three quarks.
A New Riddle To Ponder:
'Dark Halo' Reveals An Astronomical Surprise
Surprisingly, some of the oldest galaxies in the Universe have three times more stellar mass, and so many more stars, than
all current models of galaxy evolution predict.
A new finding made by the Atlas3D international team, led by an Oxford University scientist, helped to find a way to remove
the 'halo' of dark matter that has clouded previous calculations.
Mysterious Monolith At Gardom's Edge Was An Ancient Astronomical Calendar
Scientists have now reason to think that an ancient 4000-year-old stone monolith in England was likely an astronomical calendar, according to new archaeological evidence.
The 2.2 metre high monument, located in the Peak District National Park, has a striking, right-angled triangular shape that slants up towards geographic south.
The orientation and inclination of the slope is aligned to the altitude of the Sun at mid-summer.
Something New Spotted On The Sun
One day in the fall of 2011, Neil Sheeley, a solar scientist at the Naval Research Laboratory in Washington, D.C., did what he always does –
look through the daily images of the sun from NASA's Solar Dynamics Observatory (SDO).
But on this day he saw something he'd never noticed before: a pattern of cells with bright centers and dark boundaries occurring in the sun's atmosphere, the corona...
Hidden Misshapen Celestial "Wonder"
It is one of the brightest and strangest objects in the Milky Way - the corpse of a star that exploded around 1000 years ago.
Only a handful of such young supernova remnants are known.
The object named G350.1-0.3 is also incredibly small (only eight light years across) and young in astronomical terms.