Kunimoto used a technique known as 'forward modelling' to overcome these challenges. 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 days to have a size between 1.
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. It is more than double the size of the second largest, our home — the Milky Way. Both galaxies, together with 52 other, are part of the Local Group, one of many distinct groups of galaxies that are gravitationally bound to each other.
The majority of the galaxies in the Local Group are dwarf galaxies orbiting the three largest —Andromeda, Milky Way and Triangulum. The Andromeda galaxy has 25 satellite dwarf galaxies and is estimated to contain more than trillion stars within its two spiral arms. Like many other elliptical galaxies we observed, it has a black hole with more than million solar masses in its center.
But that is not the only interesting thing about its nucleus. The observations made by the Hubble Space Telescope revealed blue light surrounding the black hole. The source of the blue light was unlike anything we observed before. There appeared to be around stars arranged in a disk with a diameter of only one light year.
The blue disk is surrounded by an elliptical ring comprised of red stars, which are older and cooler than blue stars. This strange double nucleus is thought to be a result of a collision of two protogalaxies about 10 billion years ago, but this hypothesis is largely discarded and we are still not sure what caused this strange formation.
Even though there is a huge distance between the Earth and the Andromeda, it can still be seen in the night sky with the naked eye. The light from the faint smudge that can be seen on a clear moonless night takes whooping two and a half million years to reach the Earth. In areas without much light pollution, the Andromeda galaxy can be seen as a small fuzzy smudge just beneath the central bulge of the Milky Way.
It is located in the constellation Andromeda, between the W-shaped constellation Cassiopeia and the Great Square of the Pegasus constellation. It is best observed during the autumn and winter in the northern hemisphere and during the spring in the southern hemisphere.
At mid-northern latitudes it can be found between October and December in zenith — the highest point above our heads. In the prevailing theory of planet formation, called core accretion, dust grains stick together to form rocky worlds, and some of these rocky bodies then grow massive enough to attract surrounding gas, becoming gas giants like Jupiter.
Dust is made up of heavy elements, so stars depleted in these elements would have a hard time making planets in this scenario. This suggests the planet formed another way, says Alan Boss of the Carnegie Institution of Washington, DC, who was not a member of the team. He proposes an alternative mechanism that he has long championed, in which dense regions of the planet-forming disc simply collapse under their own gravity to form planets.
In this scenario, planets could form mainly from gas, without first forming a rocky core. As far as we know, the best chance a planet has to be able to support life, or be habitable by humans, is to be located within the goldilocks zone, also called habitable zone of their star system.
The goldilocks zone is the area around a star where a planet need to be located to be able to have liquid water. Statistically, however, we can infer that the probability some of the planets in the galaxy are within the goldilocks area of their stars is high. Finding new planets on distant galaxies is done using advanced data processing algorithms that try to detect the tiniest changes in areas as small as a single pixel.
Because of this, we do not really have pictures or video that refelect how planets ate such distances really look like. That best we can do with our current level of optical technology is to use this data to predict the composition of a planet and use that to make an educated guess of how it looks like through an arist impression or a 3D rendering. Elena is a Canadian journalist and researcher.
She has been looking at the sky for years and hopes to introduce more people to the wonderful hobby that is astronomy. Does the Andromeda Galaxy have planets?
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