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Post by swamprat on Jun 18, 2020 0:31:58 GMT
That's just our Milky Way galaxy, let alone all the other galaxies in the universe. And OUR Earth is the ONLY one where "intelligent" life has evolved?!?
As many as six billion Earth-like planets in our galaxy, according to new estimates
Date: June 16, 2020
Source: University of British Columbia
Summary:
There may be as many as one Earth-like planet for every five Sun-like stars in the Milky Way Galaxy, according to new estimates by University of British Columbia astronomers using data from NASA's Kepler mission.
To be considered Earth-like, a planet must be rocky, roughly Earth-sized and orbiting Sun-like (G-type) stars. It also has to orbit in the habitable zones of its star -- the range of distances from a star in which a rocky planet could host liquid water, and potentially life, on its surface.
"My calculations place an upper limit of 0.18 Earth-like planets per G-type star," says UBC researcher Michelle Kunimoto, co-author of the new study in The Astronomical Journal. "Estimating how common different kinds of planets are around different stars can provide important constraints on planet formation and evolution theories, and help optimize future missions dedicated to finding exoplanets."
According to UBC astronomer Jaymie Matthews: "Our Milky Way has as many as 400 billion stars, with seven per cent of them being G-type. That means less than six billion stars may have Earth-like planets in our Galaxy."
Previous estimates of the frequency of Earth-like planets range from roughly 0.02 potentially habitable planets per Sun-like star, to more than one per Sun-like star.
Typically, planets like Earth are more likely to be missed by a planet search than other types, as they are so small and orbit so far from their stars. That means that a planet catalogue represents only a small subset of the planets that are actually in orbit around the stars searched. Kunimoto used a technique known as 'forward modelling' to overcome these challenges.
"I started by simulating the full population of exoplanets around the stars Kepler searched," she explained. "I marked each planet as 'detected' or 'missed' depending on how likely it was my planet search algorithm would have found them. Then, I compared the detected planets to my actual catalogue of planets. If the simulation produced a close match, then the initial population was likely a good representation of the actual population of planets orbiting those stars."
Kunimoto's research also shed more light on one of the most outstanding questions in exoplanet science today: the 'radius gap' of planets. The radius gap demonstrates that it is uncommon for planets with orbital periods less than 100 days to have a size between 1.5 and two times that of Earth. She found that the radius gap exists over a much narrower range of orbital periods than previously thought. Her observational results can provide constraints on planet evolution models that explain the radius gap's characteristics.
Previously, Kunimoto searched archival data from 200,000 stars of NASA's Kepler mission. She discovered 17 new planets outside of the Solar System, or exoplanets, in addition to recovering thousands of already known planets.
Story Source:
Materials provided by University of British Columbia. Note: Content may be edited for style and length.
Journal Reference:
1. Michelle Kunimoto, Jaymie M. Matthews. Searching the Entirety of Kepler Data. II. Occurrence Rate Estimates for FGK Stars. The Astronomical Journal, 2020; 159 (6): 248 DOI: 10.3847/1538-3881/ab88b0
www.sciencedaily.com/releases/2020/06/200616100831.htm
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Post by maxxhazzard on Jul 9, 2020 18:13:36 GMT
blows my mind when I think how many planets may be out there.. the most interesting to me is Planet X... from what I understand science is contributing the gravity pull and uses math and is most likely cause by another large planet.. planet xidk about U but.. I always tend to side with math even if my eyes can't c it..
what science is saying:;;
Caltech researchers have found mathematical evidence suggesting there may be a "Planet X" deep in the solar system. This hypothetical Neptune-sized planet orbits our Sun in a highly elongated orbit far beyond Pluto. The object, which the researchers have
nicknamed "Planet Nine," could have a mass about 10 times that of Earth and orbit about 20 times farther from the Sun on average than Neptune. It may take between 10,000 and 20,000 Earth years to make one full orbit around the Sun.The announcement does not
mean there is a new planet in our solar system. The existence of this distant world is only theoretical at this point and no direct observation of the object nicknamed "Planet 9" have been made. The mathematical prediction of a planet could explain the unique orbits of
some smaller objects in the Kuiper Belt, a distant region of icy debris that extends far beyond the orbit of Neptune. Astronomers are now searching for the predicted planet ..In January 2015, Caltech astronomers Konstantin Batygin and Mike Brown announced new
research that provides evidence of a giant planet tracing an unusual, elongated orbit in the outer solar system. The prediction is based on detailed mathematical modeling and computer simulations, not direct observation.
This large object could explain the unique orbits of at least five smaller objects discovered in the distant Kuiper Belt..Planet X has not yet been discovered, and there is debate in the scientific community about whether it exists. The prediction in the Jan. 20 issue of
the Astronomical Journal is based on mathematical modeling.
Astronomers studying the Kuiper Belt have noticed some of the dwarf planets and other small, icy objects tend to follow orbits that cluster together. By analyzing these orbits, the Caltech team predicted the possibility that a large, previously undiscovered planet may
be hiding far beyond Pluto.They estimate the gravity of this potential planet might explain the unusual orbits of those Kuiper objects..Astronomers, including Batygin and Brown, will begin using the world's most powerful telescopes to search for the object in its
predicted orbit. Any object that far away from the Sun will be very faint and hard to detect, but astronomers calculate that it should be possible to see it using existing telescopes...
source:
Fesenmaier, Kimm, "Caltech Researchers Find Evidence of a Real Ninth Planet," press release, last modified January 20, 2015
Konstantin Batygin and Michael E. Brown, "Evidence for a Distant Giant Planet in the Solar System," The Astronomical Journal
Green, James, "A New Planet in our Solar System? NASA Takes a Look," video statement, last modified January 20, 2015
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Post by maxxhazzard on Feb 7, 2021 17:30:15 GMT
I dont know how to do it but, if you could post a pic of where earth is in the Milky Way it would give a visual of what a tiny spec earth is among the stars... and one billion planets is just a mathematical prediction ... don't hold me to this but,, I think there are two maybe three planets that nasa has literally found within the milky way to be able to support life based upon a probably water and light source but nothing confirmed ... and the math was done using these planets... ... peace
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Post by swamprat on Feb 7, 2021 20:18:02 GMT
Where is Earth in the Milky Way?
July 13, 2016 by Matt Williams
The Milky Way (estimated view)
For thousands of years, astronomers and astrologers believed that the Earth was at the center of our Universe. This perception was due in part to the fact that Earth-based observations were complicated by the fact that the Earth is embedded in the Solar System. It was only after many centuries of continued observation and calculations that we discovered that the Earth (and all other bodies in the Solar System) actually orbits the Sun.
Much the same is true about our Solar System’s position within the Milky Way. In truth, we’ve only been aware of the fact that we are part of a much larger disk of stars that orbits a common center for about a century. And given that we are embedded within it, it has been historically difficult to ascertain our exact position. But thanks to ongoing efforts, astronomers now know where our Sun resides in the galaxy.
Size of the Milky Way:
For starters, the Milky Way is really, really big! Not only does it measure some 100,000–120,000 light-years in diameter and about 1,000 light-years thick, but up to 400 billion stars are located within it (though some estimates think there are even more). Since one light year is about 9.5 x 1012 km (9.5 trillion km) long, the diameter of the Milky Way galaxy is about 9.5 x 1017 to 11.4 x 1017 km, or 9,500 to 11,400 quadrillion km.
It became its current size and shape by eating up other galaxies, and is still doing so today. In fact, the Canis Major Dwarf Galaxy is the closest galaxy to the Milky Way because its stars are currently being added to the Milky Way’s disk. And our galaxy has consumed others in its long history, such as the Sagittarius Dwarf Galaxy.
And yet, our galaxy is only a middle-weight when compared to other galaxies in the local Universe. Andromeda, the closest major galaxy to our own, is about twice as large as our own. It measures 220,000 light years in diameter, and has an estimated 400-800 billion stars within it.
Structure of the Milky Way:
If you could travel outside the galaxy and look down on it from above, you’d see that the Milky Way is a barred spiral galaxy. For the longest time, the Milky Way was thought to have 4 spiral arms, but newer surveys have determined that it actually seems to just have two spiral arms, called Scutum–Centaurus and Carina–Sagittarius.
The spiral arms are formed from density waves that orbit around the Milky Way – i.e. stars and clouds of gas clustered together. As these density waves move through an area, they compress the gas and dust, leading to a period of active star formation for the region. However, the existence of these arms has been determined from observing parts of the Milky Way – as well as other galaxies in our universe.
The Milky Way’s basic structure is believed to involve two main spiral arms emanating from opposite ends of an elongated central bar. Credit: T. Dame
In truth, all the pictures that depict our galaxy are either artist’s renditions or pictures of other spiral galaxies, and not the result of direct observation of the whole. Until recently, it was very difficult for scientists to gauge what the Milky Way really looks like, mainly because we’re inside it. It has only been through decades of observation, reconstruction and comparison to other galaxies that they have been to get a clear picture of what the Milky Way looks like from the outside.
From ongoing surveys of the night sky with ground-based telescopes, and more recent missions involving space telescopes, astronomers now estimate that there are between 100 and 400 billion stars in the Milky Way. They also think that each star has at least one planet, which means there are likely to be hundreds of billions of planets in the Milky Way – billions of which are believed to be the size and mass of the Earth.
As noted, much of the Milky Way’s arms is made up of dust and gas. This matter makes up a whopping 10-15% of all the “luminous matter” (i.e. that which is visible) in our galaxy, with the remainder being the stars. Our galaxy is roughly 100,000 light years across, and we can only see about 6,000 light years into the disk in the visible spectrum.
Still, when light pollution is not significant, the dusty ring of the Milky Way can be discerned in the night sky. What’s more, infrared astronomy and viewing the Universe in other, non-visible wavelengths has allowed astronomers to be able to see more of it.
The Milky Way, like all galaxies, is also surrounded by a vast halo of dark matter, which accounts for some 90% of its mass. Nobody knows precisely what dark matter is, but its mass has been inferred by observations of how fast the galaxy rotates and other general behaviors. More importantly, it is believed that this mass helps keep the galaxy from tearing itself apart as it rotates.
The Solar System:
The Solar System (and Earth) is located about 25,000 light-years to the galactic center and 25,000 light-years away from the rim. So basically, if you were to think of the Milky Way as a big record, we would be the spot that’s roughly halfway between the center and the edge.
Astronomers have agreed that the Milky Way probably has two major spiral arms – Perseus arm and the Scutum-Centaurus arm – with several smaller arms and spurs. The Solar System is located in a region in between the two arms called the Orion-Cygnus arm. This arm measures 3,500 light-years across and is 10,000 light-years in length, where it breaks off from the Sagittarius Arm.
The location of our Solar System in the Orion Spur of the Milky Way galaxy. Credit: Roberto Mura/Public Domain
The fact that the Milky Way divides the night sky into two roughly equal hemispheres indicates that the Solar System lies near the galactic plane. The Milky Way has a relatively low surface brightness due to the gases and dust that fills the galactic disk. That prevents us from seeing the bright galactic center or from observing clearly what is on the other side of it.
You might be surprised to learn that it takes the Sun 250 million years to complete one rotation around the Milky Way – this is what is known as a “Galactic Year” or “Cosmic Year”. The last time the Solar System was in this position in the Milky Way, there were still dinosaurs on Earth. The next time, who knows? Humanity might be extinct, or it might have evolved into something else entirely.
As you can see, the Milky Way alone is a very big place. And discerning our location within it has been no simple task. And as our knowledge of the Universe has expanded, we’ve come to learn two things. Not only is the Universe much larger than we could have ever imagined, but our place within in continues to shrink! Our Solar System, it seems, is both insignificant in the grand scheme of things, but also extremely precious!
www.universetoday.com/65601/where-is-earth-in-the-milky-way/
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