Solar Systems Other Than Ours
The Solar System, also called the Sun’s planetary system, is an assemblage of eight planets and hundreds of moons orbiting the star at the center of our Milky Way Galaxy.
Beyond the planets are thousands of smaller asteroids and meteoroids, many of which approach Earth’s orbit. There is also a vast reaches of very tenuous gas and dust known as the interplanetary medium.
1. L 98-59
Only 35 light-years away, the star L 98-59 (M3V C) hosts a planetary system with at least four confirmed rocky planets. One unconfirmed world, labeled L 98-59f, might be in the habitable zone, meaning it could support liquid water on its surface.
The three inner worlds at L 98-59 are prime targets for atmospheric characterization through transmission spectroscopy by the James Webb Space Telescope. In addition, the extremely large telescope under construction in Chile’s Atacama Desert is scheduled to begin observations in 2027 and may be able to observe these exoplanets from the ground.
The orbital eccentricities of the planets are low, a result that is consistent with other compact multi-planet systems with low eccentricities (0.05; Hadden & Lithwick 2014; Van Eylen & Albrecht 2015). This suggests that these planets are characterized by a modest atmosphere.
2. NGC 6768
NGC 6768 is an elliptical galaxy in the constellation Corona Australis, located about 50 million light years from Earth. It is a member of a loose cluster of galaxies.
The angular size of NGC 6768 is 1.193 by 0.907 arcmin. This is a very large galaxy, albeit one that is difficult to see.
This object is almost certainly a duplicate of NGC 6762. While the two objects have similar positions, their descriptions are very different and Dreyer never noticed that they were equal.
3. NGC 6771
NGC 6771 is an extraordinary triple system located in the constellation Pavo, which astronomers have dubbed the “Devil’s Mask”. Stars and gas have been stripped away from these galaxies and are starting to form a common envelope around them, forming the Devil’s Mask.
NGC 6769 and NGC 6770 are also part of this trio, which is receding at about 3800 kilometers per second from us. However, NGC 6771 is receding at a slightly higher rate of 4200 kilometers per second.
NGC 6771 is one of the most beautiful planetary nebulae known, showing contrasting emission and reflection nebulae in the same field. In this image, the red region glows from hydrogen gas excited by hot stars, while blue regions reflect light from a cloud of dark dust. This image was captured by NASA’s Hubble Space Telescope using three different color filters.
4. NGC 6772
Among the planets in NGC 6772, some are very similar in size to those in our own solar system. Interestingly, they orbit their host stars much closer to each other than would be expected by a random distribution of planets in their own systems.
This is the result of a very common architecture that occurs in planetary systems other than ours, according to Lorenzo Spina and colleagues from the University of Cambridge. They found that the planetary systems had a “wall” that defined their orbital distances from each other.
In this case, the wall was formed by a number of protoplanetary systems that were in a stable state and didn’t encounter larger planets like Jupiter that can disrupt their structure. The resulting system architecture, Spina and his colleagues said, was reminiscent of that found in the Kepler data.
5. NGC 6773
NGC 6773 is an extremely faint star that can be seen in the equatorial region of the celestial sky, north of the ecliptic. It is a member of the Antenna Galaxy group, which consists of two spiral galaxies that are located around 2,54 million light years from Planet Earth.
It is also a member of the Mice Galaxy group, which is a galaxy that does not have a spiral structure and has a spherical or elliptical shape. It is the closest galaxy to the Milky Way and has been observed to be in a period of colliding and merging with its companion, IC 2163. This galaxy has a very large mass and is likely very old. It also has a young population of stars and is very bright in the night sky.