Sounds like train cars going past.
Just FYI
The sun itself also affects the Earth more than previously understood. For example, according to the European Space Agency:
Scientists ... have proven that sounds generated deep inside the Sun cause the Earth to shake and vibrate in sympathy. They have found that Earth's magnetic field, atmosphere and terrestrial systems, all take part in this cosmic sing-along.
And NASA has just discovered that "space weather" causes "spacequakes" on Earth:
Researchers using NASA's fleet of five THEMIS spacecraft have discovered a form of space weather that packs the punch of an earthquake and plays a key role in sparking bright Northern Lights. They call it "the spacequake."
A spacequake is a temblor in Earth's magnetic field. It is felt most strongly in Earth orbit, but is not exclusive to space. The effects can reach all the way down to the surface of Earth itself.
And we have been having borealis' for a year or more now, right?
And in 373 B.C., ancient Greek historians recorded that just days before a quake devastated the area, strange sounds could be heard along with strange lights in the sky.
