How many solar systems are there? – The latest data collected by NASA indicates that there are 3,916 solar systems within our Milky Way. This means there are 3,916 stars with planets orbiting them in our single galaxy. Also according to the latest data, there are 5,241 confirmed exoplanets, which are planets that exist outside our solar system. Source: Getty Images
- 1 Are there other solar systems in the Milky Way galaxy?
- 2 How many habitable planets are in the Milky Way?
- 3 How many galaxies are in the universe?
- 4 What’s beyond the universe?
- 5 What is the rarest solar system?
- 6 What planet could humans live on?
- 7 Is Milky Way bigger than Andromeda?
- 8 What universe is bigger than the Milky Way?
- 9 How many universes are in space?
- 10 Is space infinite?
- 11 Does the universe ever stop?
- 12 Will the universe be forever?
- 13 Is there anything bigger than a solar system?
- 14 Is the Milky Way only our solar system?
- 15 Is there other planets in other galaxies?
- 16 Is our solar system in Andromeda Galaxy?
Are there other solar systems in the Milky Way galaxy?
The Short Answer: Our planetary system is the only one officially called “solar system,” but astronomers have discovered more than 3,200 other stars with planets orbiting them in our galaxy. Our solar system is just one specific planetary system—a star with planets orbiting around it.
Our planetary system is the only one officially called “solar system,” but astronomers have discovered more than 3,200 other stars with planets orbiting them in our galaxy. That’s just how many we’ve found so far. There are likely to be many more planetary systems out there waiting to be discovered! Our Sun is just one of about 200 billion stars in our galaxy.
That gives scientists plenty of places to hunt for exoplanets, or planets outside our solar system. But our capabilities have only recently progressed to the point where astronomers can actually find such planets. In this illustration, you can see three young planets tracing orbits around a star called HR 8799 that lies about 130 light-years from Earth. Image credit: Gemini Observatory Artwork by Lynette Cook
How many habitable planets are in the Milky Way?
Our galaxy holds at least an estimated 300 million of these potentially habitable worlds, based on even the most conservative interpretation of the results in a study released today and to be published in The Astronomical Journal.
What is the largest solar system in the Milky Way?
Scientists observe the largest solar system ever discovered Astronomers have that a huge planet and star 104 light years from Earth form the largest solar system ever seen. The planet, dubbed 2MASS J2126-8140, and its star are a full 7,000 astronomical units (AUs) apart, or a trillion miles (an AU is the distance between the Earth and the sun).
- Researchers previously thought the planet was “rogue,” roaming the galaxy alone.
- In fact, they’re so distant that if the star exploded, citizens of planet 2MASS wouldn’t know about it for a full 62 days.
- Given its bizarre characteristics, however, it’s unlikely that anyone lives there.
- For one, it’s up to 15 times the mass of, the largest planet in our own solar system.
You might think that makes it a frigid gas giant, but that’s not so.2MASS is so large that it’s on the border between a planet and brown dwarf star, and has a likely surface temperature of around 2,730 degrees F. Meanwhile, the star it orbits around, TYC 9486-927-1, is very young, with an age between 10 and 45 million years.
How many galaxies are in the universe?
Early galaxy formation – Evidence for the appearance of galaxies very early in the Universe’s history was found in 2006, when it was discovered that the galaxy IOK-1 has an unusually high redshift of 6.96, corresponding to just 750 million years after the Big Bang and making it the most distant and earliest-to-form galaxy seen at that time.
- While some scientists have claimed other objects (such as Abell 1835 IR1916 ) have higher redshifts (and therefore are seen in an earlier stage of the universe’s evolution), IOK-1’s age and composition have been more reliably established.
- In December 2012, astronomers reported that UDFj-39546284 is the most distant object known and has a redshift value of 11.9.
The object, estimated to have existed around 380 million years after the Big Bang (which was about 13.8 billion years ago), is about 13.42 billion light travel distance years away. The existence of galaxies so soon after the Big Bang suggests that protogalaxies must have grown in the so-called “dark ages”.
- As of May 5, 2015, the galaxy EGS-zs8-1 is the most distant and earliest galaxy measured, forming 670 million years after the Big Bang,
- The light from EGS-zs8-1 has taken 13 billion years to reach Earth, and is now 30 billion light-years away, because of the expansion of the universe during 13 billion years.
On 17 August 2022, NASA released a large mosaic image of 690 individual frames taken by the Near Infrared Camera (NIRCam) on the James Webb Space Telescope (JWST) of numerous very early galaxies. In May 2023, a study in the journal Nature identified an ultra-faint galaxy named JD1.
Galaxy JD1 was observed by the JWST using the near-infrared spectrograph instrument NIRSpec and was found to have a distance value of redshift z=9.79. This means that JD1 was observed at 480 million years after the Big Bang when the universe was only about 4% of its present age. Observations of this ultra-faint galaxy were aided by the effect of a gravitational lens in the galaxy cluster Abell 2744 which helped make the image of JD1 larger and 13 times brighter than it otherwise would be.
This effect and the use of the JWST’s NIRCam showed JD1’s structure to be three starforming clumps of dust and gas. One of the authors of the study Tommaso Treu said: “The combination of JWST and the magnifying power of gravitational lensing is a revolution. Different components of near-infrared background light detected by the Hubble Space Telescope in deep-sky surveys The detailed process by which the earliest galaxies formed is an open question in astrophysics. Theories can be divided into two categories: top-down and bottom-up.
In top-down correlations (such as the Eggen–Lynden-Bell–Sandage model), protogalaxies form in a large-scale simultaneous collapse lasting about one hundred million years. In bottom-up theories (such as the Searle-Zinn model), small structures such as globular clusters form first, and then a number of such bodies accrete to form a larger galaxy.
Once protogalaxies began to form and contract, the first halo stars (called Population III stars ) appeared within them. These were composed almost entirely of hydrogen and helium and may have been more massive than 100 times the Sun’s mass. If so, these huge stars would have quickly consumed their supply of fuel and became supernovae, releasing heavy elements into the interstellar medium,
What’s beyond the universe?
The universe is expanding, but what exactly is it expanding into? Nasa’s Goddard Space Flight Center Conceptual Image Lab/Science Photo Library Andrew Taubman Queens Park, New South Wales, Australia By definition, the universe is everything, so there is nothing external to it for it to expand into. It is not expanding into anything as such – everything is expanding.
- Richard Swifte
- Darmstadt, Germany
- It is all too easy to think of the big bang and the resulting expanding universe as being like an ordinary explosion, with everything expanding out from a central point.
A better analogy is to consider the surface of an inflating balloon where the surface is a two-dimensional equivalent of our three-dimensional universe. The balloon fabric is space; dots marked on this surface (equivalent to galaxies) will move apart as the balloon expands, but only because the fabric (space itself) is expanding, and without any central point for the expansion.
- If the universe is all there is, and isn’t part of a larger multiverse, then there is nothing outside it (not even a vacuum, which is still space), so it probably makes no sense to ask what it is expanding into.
- Nick Canning
- Coleraine, County Londonderry, UK
A two-dimensional being on the surface of an expanding balloon can observe all distances in its surface world getting larger. It can’t see the third dimension into which the balloon is expanding.
- We three-dimensional creatures see all the distances between galaxies expanding, indicating an inflation of space, but we can’t perceive extra space dimensions beyond our three, into which the expansion is taking place.
- Roger Leitch
- Bath, UK
- There are two parts to the answer to this question.
First, when mathematicians and physicists want to describe space – any space – the mathematical tools and techniques they use don’t depend in any way on the space being part of a higher dimensional space. So they can, for example, do geometry on the surface of a sphere without considering that the sphere is embedded in our everyday three-dimensional space.
Four-dimensional space-time is more complicated than the surface of a sphere, but the idea is the same. It is possible to calculate the shortest distance between two points, for example. Second, if space is expanding into some higher dimensional space, we can’t, with our current knowledge of physics, know anything about it.
And it may even be beyond our comprehension.
- Mike Follows
- Sutton Coldfield, West Midlands, UK
- This isn’t a question that physics can answer with our present knowledge or without some form of qualification.
The trite answer is that both space and time were created at the big bang about 14 billion years ago, so there is nothing beyond the universe. However, much of the universe exists beyond the observable universe, which is maybe about 90 billion light years across.
- Because the universe is homogenous on this scale, we imagine that what is beyond our observation looks much the same as what we can see.
- If the universe is infinite, there is nothing beyond it, by definition.
- A finite expanding universe conjures up the idea that it would have a boundary or edge, separating it from something beyond.
Of course, the universe has at least four dimensions (three for space and one for time) which is nigh on impossible for us to visualise. However, space could be represented as two dimensions, confined to the gossamer-thin surface of a sphere. You could travel in any direction on the surface without encountering an edge.
- If the radius were to increase, the “universe” would expand as ours does, but it wouldn’t be expanding into anything.
- Finally, we could speculate that our universe is part of a multiverse with many other universes beyond our own, but it is unlikely that we are expanding into them.
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What is the rarest solar system?
New work suggests four distinct star system types—and finds our own in the rarest category An imagined view from the Kepler-16 planetary system. Credit: Ron Miller
- This is a formidable task for modern telescopes but a question that computer models can easily explore.
- Through their research they noted a third system type in the observational data—a “mixed” distribution of shuffled small and large planets—and their simulations predicted one more: an “antiordered” architecture of worlds that get smaller and less massive the farther they are from their star.
These findings, which appear in two studies in Astronomy & Astrophysics, reinforce the conclusion that similar architectures are most common and suggest that ordered systems like our own are the rarest. “In a few years, I believe, we’ll have something like a ‘standard model’ of planetary formation,” Mishra says.
“And how different architectures of planetary systems emerge is a question that any standard model will have to answer.” Crucially, this research introduces a new mathematical framework for quantifying similarities among a system’s planets according to any observable characteristic, such as mass or size; one number reveals the total range of values for that characteristic among the planets, and the other reflects how widely those values typically vary from planet to planet.
This can help uncover patterns that reveal broad rules governing the birth and growth of planetary systems—as well as where those orderly rules break down. Matching their model’s predictions to observations suggests, for instance, that similar systems’ pea-pod planets emerge from sedate, low-mass protoplanetary disks, with higher-mass disks more easily making big planets—like our own system’s Jupiter—that can chaotically interact to yield the three other architectures.
- The powerful James Webb Space Telescope and other facilities may soon be able to test some of these ideas.
- University of Chicago astrophysicist Daniel Fabrycky, who was not involved with the new research, says such upcoming observations make these kinds of studies especially valuable.
- This is about building some set of concepts, around which we expect to be able to make interesting conclusions in the future,” he says.
“And that’s always a good idea because it’s more scientifically robust to make predictions and then check them, rather than observing surprising things and painting on a theoretical gloss afterward.” This article was originally published with the title “Order from Chaos” in Scientific American 328, 6, 10-12 (June 2023) doi:10.1038/scientificamerican0623-10
Which planet has life like Earth?
Kepler-452b Super-Earth exoplanet orbiting Kepler-452 Kepler-452b Artist’s impression of Kepler-452b (center), depicted here as a in the with extensive cloud cover. The actual appearance of the exoplanet is unknown. DiscoveryKepler Science team Discovery date23 July 2015 (announced) Designations KOI-7016.01 1.046 +0.019 −0.015 384.843 +0.007 −0.012 89.806 +0.134 −0.049 Star Physical characteristics Mean radius 1.5 +0.32 −0.22 5 ± 2 1.9 +1.5 −1.0 (est.) : 265 K (−8 °C; 17 °F) Kepler-452b (sometimes quoted to be an Earth 2.0 or Earth’s Cousin based on its characteristics; also known by its designation KOI-7016.01 ) is a orbiting within the inner edge of the of the star and is the only planet in the system discovered by Kepler,
It is located about 1,800 light-years (550 pc) from in the constellation of, Kepler-452b orbits its star at a distance of 1.04 AU (156 million km; 97 million mi) from its host star (nearly the same distance as Earth from the Sun), with an orbital period of roughly 385, has a mass at least five times that of Earth, and has a radius of around 1.5 times that of Earth.
It is the first potentially rocky planet discovered orbiting within the of a very sunlike star. However, it is unknown if it is entirely habitable, as it is receiving slightly more energy than Earth and could be subjected to a, The identified the exoplanet, and its discovery was announced by on 23 July 2015.
What planet could humans live on?
Flexi Says: Right now and for the foreseeable future, humans can only live on Earth. Humans have not traveled very far into space. The Moon is the only other place humans have visited. No other planet in our solar system currently has the conditions to support life as we know it on Earth.
Are there other planets like Earth in the universe?
Using data from NASA’s Transiting Exoplanet Survey Satellite, scientists have identified an Earth-size world, called TOI 700 e, orbiting within the habitable zone of its star – the range of distances where liquid water could occur on a planet’s surface.
- The world is 95% Earth’s size and likely rocky.
- Astronomers previously discovered three planets in this system, called TOI 700 b, c, and d.
- Planet d also orbits in the habitable zone.
- But scientists needed an additional year of TESS observations to discover TOI 700 e.
- This is one of only a few systems with multiple, small, habitable-zone planets that we know of,” said Emily Gilbert, a postdoctoral fellow at NASA’s Jet Propulsion Laboratory in Southern California who led the work.
“That makes the TOI 700 system an exciting prospect for additional follow up. Planet e is about 10% smaller than planet d, so the system also shows how additional TESS observations help us find smaller and smaller worlds.” Watch to learn about TOI 700 e, a newly discovered Earth-size planet with an Earth-size sibling.
Credit: NASA/JPL-Caltech/Robert Hurt/NASA’s Goddard Space Flight Center Gilbert presented the result on behalf of her team at the 241st meeting of the American Astronomical Association in Seattle. A paper about the newly discovered planet was accepted by The Astrophysical Journal Letters. TOI 700 is a small, cool M dwarf star located around 100 light-years away in the southern constellation Dorado.
In 2020, Gilbert and others announced the discovery of the Earth-size, habitable-zone planet d, which is on a 37-day orbit, along with two other worlds. The innermost planet, TOI 700 b, is about 90% Earth’s size and orbits the star every 10 days. TOI 700 c is over 2.5 times bigger than Earth and completes an orbit every 16 days. TESS monitors large swaths of the sky, called sectors, for approximately 27 days at a time. These long stares allow the satellite to track changes in stellar brightness caused by a planet crossing in front of its star from our perspective, an event called a transit.
- The mission used this strategy to observe the southern sky starting in 2018, before turning to the northern sky,
- In 2020, it returned to the southern sky for additional observations.
- The extra year of data allowed the team to refine the original planet sizes, which are about 10% smaller than initial calculations.
“If the star was a little closer or the planet a little bigger, we might have been able to spot TOI 700 e in the first year of TESS data,” said Ben Hord, a doctoral candidate at the University of Maryland, College Park and a graduate researcher at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
But the signal was so faint that we needed the additional year of transit observations to identify it.” TOI 700 e, which may also be tidally locked, takes 28 days to orbit its star, placing planet e between planets c and d in the so-called optimistic habitable zone. Scientists define the optimistic habitable zone as the range of distances from a star where liquid surface water could be present at some point in a planet’s history.
This area extends to either side of the conservative habitable zone, the range where researchers hypothesize liquid water could exist over most of the planet’s lifetime. TOI 700 d orbits in this region. Finding other systems with Earth-size worlds in this region helps planetary scientists learn more about the history of our own solar system.
Follow-up study of the TOI 700 system with space- and ground-based observatories is ongoing, Gilbert said, and may yield further insights into this rare system. “TESS just completed its second year of northern sky observations,” said Allison Youngblood, a research astrophysicist and the TESS deputy project scientist at Goddard.
“We’re looking forward to the other exciting discoveries hidden in the mission’s treasure trove of data.” TESS is a NASA Astrophysics Explorer mission led and operated by Massachusetts Institute of Technology in Cambridge, Massachusetts, and managed by NASA’s Goddard Space Flight Center.
Additional partners include Northrop Grumman, based in Falls Church, Virginia; NASA’s Ames Research Center in California’s Silicon Valley; the Center for Astrophysics | Harvard & Smithsonian in Cambridge, Massachusetts; MIT’s Lincoln Laboratory; and the Space Telescope Science Institute in Baltimore.
More than a dozen universities, research institutes, and observatories worldwide are participants in the mission.
How much bigger is IC 1101 than the Milky Way?
The Biggest of the Big – This brings us to the main point of this article – IC 1101, Located almost a billion light-years away, IC 1101 is the single largest galaxy that has ever been found in the observable universe. Just how large is it? At its largest point, this galaxy extends about 2 million light-years from its core, and it has a mass of about 100 trillion stars.
- Some estimates suggests that IC 1101 is 6 million light-years in diameter.
- To give you some idea of what that means, the Milky Way is just 100,000 light-years in diameter.
- If our galaxy were to be replaced with this super-giant, it would swallow up both Magellanic clouds, the Andromeda galaxy, the Triangulum galaxy, and almost all the space in between.
That is simply staggering. Over billions of years, galaxies the size of our own have collided and combined to form this immense structure. Telescopic observations have also revealed an interesting fact about the stars within this galaxy. Normally, blue-tinted galaxies signal active star formation, while yellow-red hues indicate a cease in the birth of new stars.
Is Milky Way bigger than Andromeda?
Could The Milky Way Be More Massive Than Andromeda? The Milky Way, as we know it today, hasn’t changed much in billions of years, and neither has, Andromeda. For a long time, we thought that Andromeda was larger, more massive, and contained far more stars than we did.
But new observations have changed the story; now, we’re not so sure. ESO/S. Guisard The Milky Way is home to the Sun, our Solar System, and hundreds of billions of stars beyond that. Yet unlike all the other galaxies out there — in our Local Group and in the Universe beyond — we have no good way to view our own galaxy from our position within it.
As a result, the full extent of our galaxy, including its total size, mass, matter content, and number of stars, remains mysterious to modern astronomers. We’ve long looked at the galaxies surrounding our local neighborhood in space and compared ourselves to them.
Although there may be more than 60 galaxies present within the Local Group, two of them dominate in every way imaginable: ourselves and Andromeda. We are the two largest, most massive galaxies around, with more stars than all the others combined. But which one is bigger? Long thought to be Andromeda, we’re now finding out the Milky Way might have a chance at being number one.
Our Local Group of galaxies is dominated by Andromeda and the Milky Way, but we still don’t know, which one dominates in terms of gravitation. While Andromeda appears to be larger in physical extent and have more stars, it may yet be less massive than we are.
Andrew Z. Colvin It might strike you as a tremendous failing on the part of astronomers that we haven’t yet learned how big, massive, or full of stars our own galaxy is, but it shouldn’t surprise you. Think about it from another point of view: imagine you were looking out at a room of people, and you wanted to determine what everyone’s eye color was.
It seems like the easiest experiment of all. All you’d have to do is get close enough to everyone in the room to see what color their eyes were, and you’d know. You’d likely know the eye color of everyone close to you right away, and through use of a tool — a camera, a pair of binoculars, a telescope, etc.
You could determine the eye color of everyone within your view. There’d only be one person in the room who’d give you trouble: yourself. When you look out at a crowd of people, you can clearly determine their eye color if they’re close, enough to you simply by looking. Without being able to look at them directly, you’d have to rely on other options such as a photograph, reflection, or another observer’s data.
public domain / Pxhere We have two ways of determining our own eye color from within our own bodies.
- We can shift our perspective outside of our own bodies. Either by asking another person in the room or by taking a selfie, we can learn what the results are and gain the missing data point of our own eye color.
- We can find an accurate-enough reflection, and learn what our eye color is from this light-echo we’re observing.
For our own bodies, this is easy enough. Many trustworthy external observers exist; camera technology is advanced, accurate, and ubiquitous; reflective surfaces like mirrors, glass, or even bodies of water are abundant. When we’re not in isolation, and live in a world with the right tools, it’s an observation that’s easy to make.
When you look at your reflection in a mirror, that’s the simplest way to determine your own eye, color. If no reflective surfaces were available, and no cameras were available. and no one else could observe you, you might never devise a method to know the answer. Pete Souza / White House But what if the right tools weren’t readily available to you? What if there was no one else outside of your own body that you could contact and whose observations you could rely on? What if there were no reflections of your own face that you could look at and view yourself to determine your eye color? And what if there was no way to take an indelible image of yourself (e.g., a photograph), enabling you to view your likeness? It’s a hard problem.
Being embedded within your own body means there’s no good way to take the critical observations yourself without the outside world around you cooperating. Well, being embedded within the Milky Way means that even our best views of our own, home galaxy from within it have fundamental limitations.
We might be able to measure the motions and positions of billions of stars, but there’s still so much that’s obscure. A map of star density in the Milky Way and surrounding sky, clearly showing the Milky Way, large and, small Magellanic Clouds, and others. But measuring the stars of the Milky Way itself is challenging, as living within the Milky Way renders us unable to view all the stars and their motions inside.
All told, the Milky Way contains some 200-400 billion stars over its disk-like extent, with the Sun located some 25,000 light years from the center. ESA/GAIA Being located in the plane of the Milky Way, 25,000 light-years from the galactic center, means that there are a number of things we cannot view optically.
- Most of the stars in the galaxy, since the dust in the plane of the Milky Way (or other structures, like nebulae or stars) obscures it.
- The bulk shapes that are traced out; we still argue about the number and size of the spiral arms, the presence or absence of arm spurs, the age and extent of the central bar, etc.
- The number and location of recent supernovae and supernova remnants, since the far side of the galaxy cannot easily be seen.
- And the transverse motions of the stars as they move around the galaxy; because we’re located in it, measuring bulk rotational motion as a function of galactic radius is challenging.
This four-panel view shows the Milky Way’s central region in four different wavelengths of light,, with the longer (submillimeter) wavelengths at top, going through the far-and-near infrared (2nd and 3rd) and ending in a visible-light view of the Milky Way.
Note that the dust lanes and foreground stars obscure the center in visible light, but not so much in the infrared. ESO/ATLASGAL consortium/NASA/GLIMPSE consortium/VVV Survey/ESA/Planck/D. Minniti/S. Guisard Acknowledgement: Ignacio Toledo, Martin Kornmesser Multi-wavelength views are helping, as infrared light of various wavelengths is more transparent to the dust, and large-scale sky mapping observatories from both the ground and in space — particularly ESA’s Gaia mission — are helping us understand the full extent of the physical properties of our galaxy.
Andromeda, on the other hand, is very close by at just a little over 2 million light-years distant. It is the largest galaxy beyond the Milky Way in terms of angular size, or the amount of space it takes up on the sky. We have engaged in a number of spectacular observing campaigns of Andromeda, most notably PHAT: the Panchromatic Hubble Andromeda Treasury, which measured and characterized the stars and dust across nearly half of our giant cosmic neighbor.
- A Mosaic of the 117 million resolved stars, plus many more unresolved ones, in the disk of the,
- Andromeda galaxy.
- Only a portion of the central bulge was imaged, but the density of stars in that region is unparalleled anywhere else in the Local Group.
- These measurements have helped scientists characterize the stars and mass present within the Andromeda Galaxy to greater precisions than ever before.
NASA, ESA, J. Dalcanton, B.F. Williams, L.C. Johnson (University of Washington), the PHAT team, and R. Gendler When we hold these two galaxies up against one another, comparing our own Milky Way to Andromeda, we find there are some stark differences that suggest Andromeda is the more dominant of the two.
- When we count the number of stars, the (infrared) Spitzer Space Telescope showed that Andromeda has approximately 1 trillion stars inside it, compared to a much smaller number with much larger uncertainties — between 200 billion and 400 billion — for the Milky Way.
- In terms of physical extent, the Andromeda Galaxy’s disk diameter is well-measured, and spans 220,000 light-years across. For comparison, the diameter of the Milky Way’s disk has long been thought to be only about half that: around 100,000 light-years.
- And in terms of the stars present, the Andromeda galaxy’s stars are much older, and its star-formation rate is much lower: only about 20-30% that of the Milky Way.
Six of the most spectacular star clusters in Andromeda. The brilliant red star in the fifth image is, actually a foreground star in the Milky Way. These star clusters represent some of the newest stars found by the Panchromatic Hubble Andromeda Treasury, allowing us to characterize star-formation rates and history of Andromeda overall.
- NASA, ESA, and Z.
- Levay (STScI); Science Credit: NASA, ESA, J.
- Dalcanton, B.F.
- Williams, L.C.
- Johnson (University of Washington), and the PHAT team So you’d probably think, if you went and measured the mass of these two galaxies, you’d find that Andromeda would be far greater in mass than the Milky Way.
But this isn’t the case at all. You see, the best way to measure galactic mass is by using the stars and globular clusters found distributed far away from the galactic center or disk: in the galaxy’s halo. Doing this for a galaxy like Andromeda is fascinating and educational, teaching us that the massive halo extends for approximately a million light-years in all directions, and contains a large amount of mass in this halo as well, in terms of both gas and dark matter.
- Although there are large uncertainties, the total mass estimates of Andromeda range up to,
- These estimates are so different because they’re arrived at by using different techniques, which poses an interesting puzzle at present.
- This diagram shows how scientists determined the size of the halo of the Andromeda galaxy: by,
looking at absorption features from distant quasars, whose light either did or did not pass through the halo surrounding Andromeda. Where the halo is present, its gas absorbs some of the quasar light and darkens it across a very small wavelength range.
- By measuring the tiny dip in brightness at that specific range, scientists could tell how much gas is between us and each quasar.
- NASA, ESA, and A.
- Feild (STScI) By measuring the motions of globular clusters within our own Milky Way, however, we don’t have to rely only on the radial (along our line-of-sight) measurement, but can obtain transverse (moving perpendicular to our line-of-sight) motions as well.
A combination of new data has given us a total of 46 globular clusters with distances reaching as far as 130,000 light-years from Earth, and was able to pin down the Milky Way’s mass more accurately than ever before. The result? The Gaia data alone indicates a mass of 1.3 trillion solar masses, while the combined Gaia/Hubble data (where Hubble captures the more distant globular clusters), with an uncertainty of less than 100 billion solar masses.
A map of the nearest globular clusters surrounding the Milky Way’s center. The globular clusters, closest to the galactic center have a higher metal content than the ones on the outskirts, but measuring the 3D motions of these clusters enables us to infer how much mass is present, total, throughout the Milky Way.
William E. Harris / McMaster U., and Larry McNish / RASC Calgary In other words, even though the stars tell a different story, the overall mass shows that the Milky Way is likely as massive as the most massive estimates for Andromeda. If the radio observations of Andromeda is correct, our galaxy may even be nearly twice as massive as Andromeda.
What’s even more interesting is that another recent study,, indicates that the extent of the Milky Way’s disk may be much larger than previously estimated: more like 170,000 light-years in diameter, rather than 100,000 light-years. Summing it all up, it looks like the Milky Way may be larger in extent and more massive in nature than we realized, while Andromeda may be more diffuse, spread-out, and less massive than we previously suspected.
Located just outside the Big Dipper, the objects M81 and M82 have often been used as an analogy for, Andromeda and the Milky Way. While Andromeda still has more stars, it’s possible that the Milky Way is nearly as large, nearly as luminous, and may even be more massive.
- More data is needed to know for certain.
- Markus Schopfer / c.c.-by-2.5 For a very long time, our observations of Andromeda and the Milky Way seemed to indicate that we were second to Andromeda in pretty much every way as far as our local neighborhood was concerned.
- But the real thing that’s changing is our measurements are improving, and we’re learning just how difficult it is to accurately measure total mass values even in our own backyard.
We’re understanding and quantifying our uncertainties, and are realizing just how significant they are. There are stellar streams, ancient and recent gravitational interactions, and unknown initial conditions and past histories for every galaxy in question.
When we measure these stars and clusters, we are only measuring velocities, yet to understand total mass, we want to measure accelerations, and that’s where the difficulty lies. It’s very much possible that our Milky Way is as massive or even more massive than Andromeda. As always, it will take more and better science to uncover the final answer.
: Could The Milky Way Be More Massive Than Andromeda?
What universe is bigger than the Milky Way?
Portion of Hubble Extreme Deep Field, Every spot and smudge in this image is a galaxy. Credit: NASA, ESA Many people are not clear about the difference between our Solar System, our Milky Way Galaxy, and the Universe. Let’s look at the basics. Our Solar System consists of our star, the Sun, and its orbiting planets (including Earth), along with numerous moons, asteroids, comet material, rocks, and dust. On that scale with our Solar System in your hand, the Milky Way Galaxy, with its 200 – 400 billion stars, would span North America ( see the illustration on the right ). Galaxies come in many sizes. The Milky Way is big, but some galaxies, like our Andromeda Galaxy neighbor, are much larger.
- The universe is all of the galaxies – billions of them! NASA’s telescopes allow us to study galaxies beyond our own in exquisite detail, and to explore the most distant reaches of the observable universe.
- The Hubble Space Telescope made one of the deepest images of the universe, called the Hubble Extreme Deep Field (image at the top of this article).
Soon the James Webb Space Telescope will be exploring galaxies forming at the very beginning of the universe. You are one of the billions of people on our Earth. Our Earth orbits the Sun in our Solar System. Our Sun is one star among the billions in the Milky Way Galaxy.
- Our Milky Way Galaxy is one among the billions of galaxies in our Universe.
- You are unique in the Universe! You can observe objects in our solar system and even see other galaxies at a star party near you-and rest assured that everything you are seeing is a part of the same universe as you! Find out more by using our club and event finder and connect with your local astronomy club.
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How many universes are in space?
Arguments against the multiverse theory – Falsifiability There is no way for us to ever test theories of the multiverse. We will never see beyond the observable universe, so if there is no way to disprove the theories, should they even be given credence? Occam’s razor Sometimes, the simplest ideas are the best.
Is it possible to travel to another galaxy?
From Wikipedia, the free encyclopedia Intergalactic travel is the hypothetical crewed or uncrewed travel between galaxies, Due to the enormous distances between the Milky Way and even its closest neighbors —tens of thousands to millions of light-years —any such venture would be far more technologically and financially demanding than even interstellar travel,
- Intergalactic distances are roughly a hundred-thousandfold (five orders of magnitude) greater than their interstellar counterparts.
- The technology required to travel between galaxies is far beyond humanity’s present capabilities, and currently only the subject of speculation, hypothesis, and science fiction,
However, theoretically speaking, there is nothing to conclusively indicate that intergalactic travel is impossible. There are several hypothesized methods of carrying out such a journey, and to date several academics have studied intergalactic travel in a serious manner.
Is space infinite?
The curvature of the cosmos – Cosmologists aren’t sure if the universe is infinitely big or just extremely large. To measure the universe, astronomers instead look at its curvature. The geometric curve on large scales of the universe tells us about its overall shape.
If the universe is perfectly geometrically flat, then it can be infinite. If it’s curved, like Earth’s surface, then it has finite volume. Current observations and measurements of the curvature of the universe indicate that it is almost perfectly flat. You might think this means the universe is infinite.
But it’s not that simple. Even in the case of a flat universe, the cosmos doesn’t have to be infinitely big. Take, for example, the surface of a cylinder. It is geometrically flat, because parallel lines drawn on the surface remain parallel (that’s one of the definitions of “flatness”), and yet it has a finite size.
- The same could be true of the universe: It could be completely flat yet closed in on itself.
- But even if the universe is finite, it doesn’t necessarily mean there is an edge or an outside.
- It could be that our three-dimensional universe is embedded in some larger, multidimensional construct.
- That’s perfectly fine and is indeed a part of some exotic models of physics.
But currently, we have no way of testing that, and it doesn’t really affect the day-to-day operations of the cosmos. And I know this is extremely headache-inducing, but even if the universe has a finite volume, it doesn’t have to be embedded.
Is time Finite or Infinite?
The Essential Context of Time — Chris Colbert All we have is time. I know, I know a heady proposition, but I think it might actually be true. Think about it for a second. Time defines our existence. It provides the bookends for pretty much everything. And the funny thing about time is that its context is both finite and infinite.
- As humans, it offers us an explicit and unimpeachable beginning and end.
- We are born, we live and we die.
- That’s pretty much it.
- As a universe, a vast collection of animate and inanimate objects, time is infinite.
- Even if there was a beginning, and there might be a big bang end, it won’t really be an end.
The energy left behind will become something else; the end will be a beginning. As we tend to ignore the infinite and unfathomable nature of the universe (and our infinitesimal role in it) we also ignore the finite truth of our own existence. And therein lie a problem and an opportunity.
- We approach our daily lives as if we will live forever, and in that infinite view of what is decidedly finite, we tend to make the wrong choices or worse, no choices at all.
- Our actions are fueled by the belief that we can always do it or deal with it tomorrow, and that just fundamentally isn’t true.
There may not be a tomorrow, which suggests we should act differently today. In the book I have been writing I explore this topic of finite time and how it should impact our choices. A brief excerpt is here: You know that expression “Life is too short”? Well, this cutting edge philosopher and statesman from around 20 AD named Lucius Seneca the Younger penned a compelling treatise suggesting it wasn’t an issue of length but rather of the choices we make along the way that determines a sufficient and worthy life.
He opined: “It is not that we have a short space of time, but that we waste much of it. Life is long enough, and it has been given in sufficiently generous measure to allow the accomplishment of the very greatest things if the whole of it is well invested.” Well invested means making the right choices which arguably would be made better if we all recognized that our time was finite, our days on this earth numbered, which in fact they are.
Imagine for a second (more time context) that there was a flashing red LED display in your kitchen that was a countdown of how many hours you have left on earth? Wouldn’t it change your time management approach? Wouldn’t you think twice about the investments you were making or not making, about how you were frittering away your precious life, or perhaps avoiding taking the risks to get what you really want? The consequences are huge and yet we all have a hard time seeing them because we have a hard time embracing the essential context of time.
In her book The Top Five Regrets of the Dying, ex-hospice nurse and now author Bonnie Ware consolidated years of listening to the about-to-be departed and summarized their final thoughts (regrets) down to this: 1. I wish I’d had the courage to live a life true to myself, not the life others expected of me.2.
I wish I hadn’t worked so hard.3. I wish I’d had the courage to express my feelings.4. I wish I had stayed in touch with my friends.5. I wish that I had let myself be happier. Interesting right? And particularly interesting when you look at those regrets through the context of time.
I am pretty sure that if we all embraced our time as finite, our end as sort of near, we’d find an infinite pool of courage, we’d walk away from work that did not honor or nurture us, we’d start telling the truth about how we feel, the good, the bad and the ugly, we’d reach out to friends and maybe even tell them we love them, we’d wake up every living day and be thankful that we were still alive and be excited about what we were going to do with our finite minutes, hours, and days ahead.
Fundamentally we’d look at every action through the lens of this simple question: “Is this expenditure of my time worth the loss of my time?” My bet is that we’d start making very different investment decisions. My guess is that we’d stop looking at our phones (85 times a day according to one study), we might start making more intentional plans on how we’re going to use our time (What are you doing this weekend?), and we might stop giving others our time without seeking something in return.
- And we might decide to make the most radical investment of all; we might decide to do nothing with our time in order to do something meaningful with our time.
- By that I mean we might invest more of our time in just being, sitting with our thoughts, contemplating our past, present, and future, and planning how we’re going to use the rest of our time on earth to make the most of our time.
The challenge with all this, as logical as it is, is that we don’t really believe it. Or better said, our primal beings won’t let us accept it. We are hard wired to survive and in that wiring comes a capacity to delude ourselves in order to avoid what we perceive as undue risk taking and ensure that our Maslow-codified basic needs are met.
- The rationale for living as if our time is finite is overwhelmed by our reptilian brain and its slithering need to just exist.
- The result is the five regrets.
- And under-funded 401ks.
- Chronic health conditions.
- A litany of unintended and not-so-good consequences that are largely derived from our inability to embrace the simple truth that we are not immortal and that this show is going to end, and maybe soon.
Ironically it appears as if death is the only antidote to all this. The problem, of course, is that our death is, well, the end of our time. So even when we finally get it we have no time left to do anything about it, other than feel regret. But the death of loved ones can serve as a shock treatment of sorts, an all too stark reminder that time is finite and an inner questioning of why we are wasting ours.
Sadly but truly, too many of us need the death of another to value the life (and time) we have. We need a calamity to force clarity, we need tears to motivate us to seek more joy, we need the discomfort of it all to value what we have in the here and now. Loss motivates an appreciation of living and a desire to live it with more gusto, to take more risk, to make better choices that align with who we really are and how we really want to be.
For a few days and maybe even weeks after the phone call or the funeral, we get it. And then we lose it. The clarity fades, the motivation to live our lives differently dissipates, and then we fall back to abusing our time, under using our time, living in the lala-land where we think our time is infinite.
Until the next loss, or until we wake up on our deathbed surrounded by pillows of regret. It does not have to be this way. Yes, our time is finite. But how we choose to invest it is, well, an infinite choice. We can choose to embrace the essential context of time as good news not bad. As motivation not threat.
As an omnipresent friend, not a lurking enemy. As Seneca shared, it’s not about how much time we have; it’s about how we choose to invest it. That may be the only choice that really matters in the end. Of time that is. : The Essential Context of Time — Chris Colbert
Does the universe ever stop?
Ask Dr. Universe: Where does the universe end? Washington State University Dr. Universe: Where does the universe end? – Oriah, Pullman Dear Oriah, When you look up at the night sky, it can feel like the universe is a big blanket of stars above you. But unlike a blanket, the universe doesn’t have corners and edges.
Far beyond what humans can see, the universe keeps going. As far as humans know, it never stops. When I saw your question, I went directly to my friend Michael Allen to learn more. He is a senior instructor of Physics and Astronomy at Washington State University. The universe is bigger than the biggest thing you’ve ever seen.
It’s bigger than the biggest thing we can imagine. It’s so big that even your question has more than one very big answer. Allen explained that you can think of the universe kind of like a rubber band. If you look at a rubber band’s flat surface, you can see it has no beginning and no end.
- It keeps going around and around in a loop.
- Imagine you drew dots on that rubber band.
- If you pull on the rubber band, what happens? The rubber band stretches, and the dots move farther apart.
- The universe is like that.
- The distance between all its galaxies, planets and stars is stretching all the time, like dots on a rubber band.
It never ends, but it’s also constantly expanding. Scientists don’t think there is a true edge of the universe. But there’s an end to what humans can see of the universe. This is called the edge of the observable universe. It’s the farthest we can see based on how we get information from light.
- Everything you see depends on light bouncing off objects.
- Light reflects off the things around you, and your eye absorbs it.
- When you look at your hand, you see your hand in that exact moment.
- But when you look at a star, you’re actually seeing that star in the past.
- That’s because the light has to travel a very long time to reach your eyes.
The farther away the star, the longer it takes. It takes light from the nearest star, the Sun, eight minutes to get to our eyes on Earth. Light from the next nearest star, Proxima Centauri, takes about four years to get to us! Light moves very fast – about 186,000 miles per second – but the universe is very big.
So, the farthest edge of the observable universe is the oldest light we can see – about 13.8 billion years in the past. But that edge is just what we can see from Earth. Earth isn’t the center of the universe. It’s just one location. The edge of the observable universe depends on where you are located. If we were somewhere else in the universe, we would have a different view.
No matter where you are, you can think of yourself as a time traveler of sorts. When you gaze up at the stars, you’re looking up at the past. Sincerely, Dr. Universe : Ask Dr. Universe: Where does the universe end?
Will the universe be forever?
Is there an end? – If you could keep going out, as far as you wanted, would you just keep passing by galaxies forever? Are there an infinite number of galaxies in every direction? Or does the whole thing eventually end? And if it does end, what does it end with? These are questions scientists don’t have definite answers to yet.
Many think it’s likely you would just keep passing galaxies in every direction, forever, In that case, the universe would be infinite, with no end. Some scientists think it’s possible the universe might eventually wrap back around on itself – so if you could just keep going out, you would someday come back around to where you started, from the other direction.
One way to think about this is to picture a globe, and imagine that you are a creature that can move only on the surface. If you start walking any direction, east for example, and just keep going, eventually you would come back to where you began. If this were the case for the universe, it would mean it is not infinitely big – although it would still be bigger than you can imagine.
In either case, you could never get to the end of the universe or space. Scientists now consider it unlikely the universe has an end – a region where the galaxies stop or where there would be a barrier of some kind marking the end of space. But nobody knows for sure. How to answer this question will need to be figured out by a future scientist.
Written by Jack Singal, Associate Professor of Physics, University of Richmond. This article was first published in The Conversation,
Is there anything bigger than a solar system?
The solar system is the smallest when it is compared with the size of a galaxy and the Universe. Most of the hundreds of billions of stars in our galaxy are thought to have planets of their own, and the Milky Way is but one of perhaps 100 billion galaxies in the Universe.
Has anyone been outside the solar system?
What is Voyager 1? – No spacecraft has gone farther than NASA’s Voyager 1. Launched in 1977 to fly by Jupiter and Saturn, Voyager 1 crossed into interstellar space in August 2012 and continues to collect data.
Voyager 1 and its sister ship Voyager 2 have been flying longer than any other spacecraft in history. Not only are the Voyager missions providing humanity with observations of truly uncharted territory, but they are also helping scientists understand the very nature of energy and radiation in space—key information for protecting future missions and astronauts. Voyager 1 carries a copy of the Golden Record—a message from humanity to the cosmos that includes greetings in 55 languages, pictures of people and places on Earth and music ranging from Beethoven to Chuck Berry’s “Johnny B. Goode.”
|Nation||United States of America (USA)|
|Objective(s)||Jupiter Flyby, Saturn Flyby|
|Spacecraft Mass||1,592 pounds (721.9 kilograms)|
|Mission Design and Management||NASA / JPL|
|Launch Vehicle||Titan IIIE-Centaur (TC-6 / Titan no.23E-6 / Centaur D-1T)|
|Launch Date and Time||Sept.5, 1977 / 12:56:01 UT|
|Launch Site||Cape Canaveral, Fla. / Launch Complex 41|
|Scientific Instruments||1. Imaging Science System (ISS) 2. Ultraviolet Spectrometer (UVS) 3. Infrared Interferometer Spectrometer (IRIS) 4. Planetary Radio Astronomy Experiment (PRA) 5. Photopolarimeter (PPS) 6. Triaxial Fluxgate Magnetometer (MAG) 7. Plasma Spectrometer (PLS) 8. Low-Energy Charged Particles Experiment (LECP) 9. Plasma Waves Experiment (PWS) 10. Cosmic Ray Telescope (CRS) 11. Radio Science System (RSS)|
Has every star got a solar system?
Flexi Says: Scientists have recently determined that nearly every star you can see in the sky is likely to have planets. Our home planetary system is called the solar system because Sol is the astronomical name of the Sun, our home star. Systems of planets orbiting other stars are simply called planetary systems.
Is the Milky Way only our solar system?
|The Galactic Center as seen from Earth ‘s night sky (featuring the telescope’s laser guide star )|
|Observation data ( J2000 epoch )|
|Right ascension||17 h 45 m 40.03599 s|
|Declination||−29° 00′ 28.1699″|
|Distance||7.935–8.277 kpc (25,881–26,996 ly )|
|Type||Sb; Sbc; SB(rs)bc|
|Mass||1.15 × 10 12 M ☉|
|Number of stars||100–400 billion ( (1–4) × 10 11 )|
|Size||26.8 ± 1.1 kpc (87,400 ± 3,590 ly ) (diameter; 25.0 mag/arcsec 2 B-band isophote )|
|Thickness of thin disk||220–450 pc (718–1,470 ly)|
|Thickness of thick disk||2.6 ± 0.5 kpc (8,500 ± 1,600 ly)|
|Angular momentum||~ 1 × 10 67 J s|
|Sun’s Galactic rotation period||212 Myr|
|Spiral pattern rotation period||220–360 Myr|
|Bar pattern rotation period||160–180 Myr|
|Speed relative to CMB rest frame||552.2 ± 5.5 km/s|
|Escape velocity at Sun’s position||550 km/s|
|Dark matter density at Sun’s position||0.0088 +0.0024 −0.0018 M ☉ pc −3 ( 0.35 +0.08 −0.07 GeV cm −3 )|
The Milky Way is the galaxy that includes the Solar System, with the name describing the galaxy’s appearance from Earth : a hazy band of light seen in the night sky formed from stars that cannot be individually distinguished by the naked eye, The term Milky Way is a translation of the Latin via lactea, from the Greek γαλακτικὸς κύκλος ( galaktikòs kýklos ), meaning “milky circle”.
From Earth, the Milky Way appears as a band because its disk-shaped structure is viewed from within. Galileo Galilei first resolved the band of light into individual stars with his telescope in 1610. Until the early 1920s, most astronomers thought that the Milky Way contained all the stars in the Universe,
Following the 1920 Great Debate between the astronomers Harlow Shapley and Heber Doust Curtis, observations by Edwin Hubble showed that the Milky Way is just one of many galaxies. The Milky Way is a barred spiral galaxy with a D 25 isophotal diameter estimated at 26.8 ± 1.1 kiloparsecs (87,400 ± 3,590 light-years ), but only about 1,000 light-years thick at the spiral arms (more at the bulge).
Recent simulations suggest that a dark matter area, also containing some visible stars, may extend up to a diameter of almost 2 million light-years (613 kpc). The Milky Way has several satellite galaxies and is part of the Local Group of galaxies, which form part of the Virgo Supercluster, which is itself a component of the Laniakea Supercluster,
It is estimated to contain 100–400 billion stars and at least that number of planets, The Solar System is located at a radius of about 27,000 light-years (8.3 kpc) from the Galactic Center, on the inner edge of the Orion Arm, one of the spiral-shaped concentrations of gas and dust.
The stars in the innermost 10,000 light-years form a bulge and one or more bars that radiate from the bulge. The Galactic Center is an intense radio source known as Sagittarius A*, a supermassive black hole of 4.100 (± 0.034) million solar masses, Stars and gases at a wide range of distances from the Galactic Center orbit at approximately 220 kilometers per second (136 miles per second).
The constant rotational speed appears to contradict the laws of Keplerian dynamics and suggests that much (about 90%) of the mass of the Milky Way is invisible to telescopes, neither emitting nor absorbing electromagnetic radiation, This conjectural mass has been termed ” dark matter “.
Is there other planets in other galaxies?
From Wikipedia, the free encyclopedia An extragalactic planet, also known as an extragalactic exoplanet or an extroplanet, is a star -bound planet or rogue planet located outside of the Milky Way Galaxy, Due to the immense distances to such worlds, they would be very hard to detect directly.
Are there other suns in other galaxies?
There Is Only One Sun The word ‘sun’ is often used to describe many multitudes of stars in our galaxy and beyond, but doing so is a misnomer. The Sun is the name of our star, just as Sirius is the brightest star in Canis Major.
Is our solar system in Andromeda Galaxy?
|A visible light image of the Andromeda Galaxy. Messier 32 is to the left of the galactic nucleus and Messier 110 at the bottom right.|
|Observation data ( J2000 epoch )|
|Right ascension||00 h 42 m 44.3 s|
|Declination||+41° 16′ 9″|
|Redshift||z = −0.001004 (minus sign indicates blueshift )|
|Helio radial velocity||−301 ± 1 km/s|
|Distance||765 kpc (2.50 Mly )|
|Apparent magnitude (V)||3.44|
|Absolute magnitude (V)||−21.5|
|Mass||(1.5 ± 0.5) × 10 12 M ☉|
|Number of stars||~1 trillion (10 12 )|
|Size||46.56 kpc (152,000 ly ) (diameter; 25.0 mag/arcsec 2 B-band isophote )|
|Apparent size (V)||3.167° × 1°|
|M 31, NGC 224, UGC 454, PGC 2557, 2C 56 (Core), CGCG 535-17, MCG +07-02-016, IRAS 00400+4059, 2MASX J00424433+4116074, GC 116, h 50, Bode 3, Flamsteed 58, Hevelius 32, Ha 3.3, IRC +40013|
The Andromeda Galaxy is a barred spiral galaxy and is the nearest major galaxy to the Milky Way, where the Solar System resides. It was originally named the Andromeda Nebula and is cataloged as Messier 31, M31, and NGC 224, Andromeda has a diameter of about 46.56 kiloparsecs (152,000 light-years ) and is approximately 765 kpc (2.5 million light-years) from Earth,
- The galaxy’s name stems from the area of Earth’s sky in which it appears, the constellation of Andromeda, which itself is named after the princess who was the wife of Perseus in Greek mythology,
- The virial mass of the Andromeda Galaxy is of the same order of magnitude as that of the Milky Way, at 1 trillion solar masses (2.0 × 10 42 kilograms ).
The mass of either galaxy is difficult to estimate with any accuracy, but it was long thought that the Andromeda Galaxy was more massive than the Milky Way by a margin of some 25% to 50%. This has been called into question by early 21st-century studies indicating a possibly lower mass for the Andromeda Galaxy and a higher mass for the Milky Way.
The Andromeda Galaxy has a diameter of about 46.56 kpc (152,000 ly), making it the largest member of the Local Group of galaxies in terms of extension. The Milky Way and Andromeda galaxies are expected to collide in around 4–5 billion years, merging to potentially form a giant elliptical galaxy or a large lenticular galaxy,
With an apparent magnitude of 3.4, the Andromeda Galaxy is among the brightest of the Messier objects, and is visible to the naked eye from Earth on moonless nights, even when viewed from areas with moderate light pollution,