Alternate Planets, Suns, Stars, and Solar Systems Thread

A piece of world building for an ongoing project of mine, where a beleaguered Human polity fights a seemingly endless war against a mysterious alien foe.

How big is human space in this setting?
Just in case anyone wants it for something (no credit needed), here is a map of terraformed Venus with a more temperate climate. A couple new landmasses have also been added.

Green Venus.png
Nice. What will you be using it in?
I've been wanting to do an alternate history where Venus is the inhabitable world, but its a bit more like the pulp science fiction novels-very tropical type climate, swamps, lizards and dragon type creatures. Basically, a what if a humans evolving there and their culture as they begin looking to space.

Also, I just love terraformed Venus maps :D
Here is something I've been working on, the setting of a story I've been writing. Its also the first map I've ever made. Comments welcome
Barnards_Star finished.png

“Barnard’s Star is an M4-class red dwarf star and the second closest star system to the Solar System at about 5.9 lightyears away. With a mass less than 15% that of Sol and a proportionately similar radius, Barnard’s Star is a small and dim star. Barnard’s Star is orbited by two planets, an unknown number of asteroids and three known dwarf planets.

Van de Kamp’s World is the outer of the two planets, whose existence was theorized by the eponymous astronomer but not proven until 2018. It is a Super-Earth with about three and a half times Earth’s mass and roughly 1.4 times Earth’s radius. Orbiting at 0.4 AU from Barnard’s Star, VdK’s World is a frigid planet far outside the habitable zone, with a surface mostly covered in ice. It is the largest known source of volatiles in the system. The planet possesses two large moons (the approximate size of Io and Pluto) named Lubbertus and Engelina after Peter Van de Kamp’s parents, as well as half a dozen known smaller satellites.

The inner and smaller of Barnard’s Star’s two planets is known as Gatewood’s World, discovered by the Daedalus Crater Radio Telescope. Classified as a near-Earth sized world, Gatewood’s World is slightly smaller and approximately as massive as Venus. The planet has a relatively thin atmosphere (~90 millibars on the surface) and like most terrestrial planets orbiting red dwarfs is tidally locked. Despite these qualities, the fact that the planet’s 0.07 AU orbit puts it directly in Barnard’s Star’s habitable zone makes Gatewood a prospect for terraforming.

Aside from centuries worth of observation, humanity’s interaction with Barnard’s Star started when the Gan De-class interstellar probe Niú, one of several launched by the PRC prior to World War 3, flew within 100 AU of the system in 2093, transmitting the most detailed images of the system ever seen up to that point. In 2139 the ISV Mushika was launched towards the system, the third ISV ever launched. Like its older sisters the Mushika carries its passengers in cryostasis for the near-entirety of its 31 year journey. The colonists, mainly a mix of Brazilians and Indians (the ship being a joint venture between the two members of SoTO) are due to arrive in-system in 2170. Time will tell what they’ll accomplish...
-Taken from Nearby Stars for the Astronomically Interested, published 2168

“Astrographical report #039 summary: We have tentatively mapped the extent of Barnard’s Star’s Oort Cloud, Emerson Belt (Kuiper equivalent), and Edward Belt. Several metallic asteroids have been identified and designated as potential mining targets. Additionally two additional dwarf planets have been identified in the outer system. We postulate their highly eccentric orbits are the reason for the provw Niú missing them in it’s surveys. They have temporarily been designated MUSHIKA-1 and MUSHIKA-2 until proper names can be determined. See full report for more details.”
-Communication sent to Sol from ISV Mushika on January 2nd, 2170 by Computer Systems head Bhuta Vahana Yantra. Sent as the vessel was traversing the Barnard’s Star Oort Cloud on final approach to the system.
Here is something I've been working on, the setting of a story I've been writing. Its also the first map I've ever made. Comments welcome

I like the idea and look forward to more work in the serie. Also from my calculations Van de Kemp's World have a gravity of 2,5 G, which is survivable but not something you would want to live on.
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I made another map, this time of an alternate Earth where the only recognizable continents are the Americas. Once again, feel free to use for a map game/conworld/whatever.

Alternate Earth.png

This is a WIP at the moment, have been going at it for a few days but some things about it seem a bit off. I'm stuck at the moment so if you guys have any ideas of what I could add/remove it would be much appreciated.
Thinking about the "Mars as big as Moon" hoax, I was wondering what the actual effects would be of a Mars-sized body orbiting roughly twice as far from Earth as the Moon. Would this have any significant effects on Earth and the Moon (such as increased volcanism and convection, higher tides, etc) or would the distance be enough to effectively cancel out any gravitational effect of alt-Mars on Earth? Additionally, what if rather than appearing to be the same size as the Moon, alt-Mars orbited out far enough to appear only half its size, or a quarter, or an eighth?