NASA's adventurous Parker Solar Probe spacecraft zips past the sun again today

Quote from the article
"The exact time of the closest approach to the sun, or perihelion, will be around 8:16 a.m. EST (1316 GMT), when the spacecraft will be traveling at an incredible speed of around 364,639 mph (586,829 kph).
Amazingly, this speed, 200 times faster than a bullet fired by a rifle, isn't the record velocity for the craft. On Nov. 21, 2021, the Parker Solar Probe achieved a slightly higher speed of 364,621 mph (586,000 kph) during its 10th solar flyby, becoming the fastest spacecraft ever built, although it will break that record later in its mission."

So how is the quoted speed of 364,621 mph on Nov 21 2021 higher than todays quoted speed of 364,639 mph ? 🤔
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Dec 21, 2019
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It won't be "ten times closer" than Mercury. "Ten times" literally means 1000%, and "closer" (like other diminuitive quantifiers like "smaller" or "cheaper") cannot be more than 100% (because 100% closer would be at the surface of the sun.) At perihlion, the probe will be 90% closer than Mercury's orbit, or (better stated) one-tenth the distance. People reading scientific articles are interested in science, and therefore are likely comfortable with correct terminology. Please use it.
Yes, it bugs me too. "Ten times closer..." is ten times what? What number do you multiply by ten? What are the units on that number? There are no such things as "units of closeness".
"One tenth the distance" makes perfect sense, we should use it.