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2026-09-09 Science & Technology

Astronomer Ananeva: The Solar System may have once had five giant planets

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Posted by badanov 2026-09-09 00:00|| E-Mail|| Front Page|| [247 views ] Top

1 Since the article mentioned that the "fifth planet" was a lightweight gas giant that orbited very close to the sun, instead of being ejected, that planet could have had its gas atmosphere blown away by the sun, leaving a rocky core that we know as Mercury today!

This might also help explain why Venus has such a hot atmosphere and a weird rotation as well.

Posted by Seeking Cure For Ignorance 2026-09-09 05:37|| 2026-09-09 05:37|| Front Page Top

2 Discussion on reddit:

What if Mercury is the leftover core of a once hot Jupiter whose atmosphere was blown off?

Posted by Skidmark 2026-09-09 06:26|| 2026-09-09 06:26|| Front Page Top

3 /\Beyond all of this and that, what is there ?

Posted by Besoeker 2026-09-09 07:18|| 2026-09-09 07:18|| Front Page Top

4 Well, there reportedly is a mass of dark matter out by Uranus.

Posted by Skidmark 2026-09-09 07:21|| 2026-09-09 07:21|| Front Page Top

5 Generally observable, but there is no denying the latent Skidmarks.

Posted by Besoeker 2026-09-09 07:28|| 2026-09-09 07:28|| Front Page Top

6 Kinda like meteor and fireball atmospheric ionization trails.

Posted by Skidmark 2026-09-09 12:56|| 2026-09-09 12:56|| Front Page Top

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