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Third set of new results from Parker released

The scientists using the Parker Solar Probe on June 2nd released their third set of new results as part of a special issue of the journal Astronomy & Astrophysics.

The latest articles include data analysis, theory, and modeling. Among the major topics covered are magnetic switchbacks first discovered by Parker Solar Probe, the role of waves in heating solar plasma, solar angular momentum, the near-Sun dust environment, and the diversity of small energetic-particle events.

The most interesting paper I think is the one describing data that lends strong weight to the theory, proposed in 1929 by astronomer Henry Norris Russell, that a dust-free zone exists close to the Sun and all stars. From the abstract:

The observed brightness decrease in the axis of symmetry is interpreted as the signature of the existence of a dust density depletion zone between about 19 [solar radii] and 3 [solar radii] which at the inner limit of WISPR’s field of view of 7.65 [solar radii] has a dust density that is ~5% lower than the density at 19 [solar radii], instead of the expected density which is three times if no depletion zone exists.

In plain English, the data shows that from about 1.3 million to 8.2 million miles from the Sun Parker found far less dust than predicted by other models. As the probe continues to lower its orbit and get closer to the Sun with each fly-by these numbers will be better refined, and are likely to in the end prove Russell’s hypothesis.

Pioneer cover

From the press release: From the moment he is handed a possibility of making the first alien contact, Saunders Maxwell decides he will do it, even if doing so takes him through hell and back.

Unfortunately, that is exactly where that journey takes him.

The vision that Zimmerman paints of vibrant human colonies on the Moon, Mars, the asteroids, and beyond, indomitably fighting the harsh lifeless environment of space to build new societies, captures perfectly the emerging space race we see today.

He also captures in Pioneer the heart of the human spirit, willing to push forward no matter the odds, no matter the cost. It is that spirit that will make the exploration of the heavens possible, forever, into the never-ending future.

Available everywhere for $3.99 (before discount) at amazon, Barnes & Noble, all ebook vendors, or direct from the ebook publisher, ebookit. And if you buy it from ebookit you don't support the big tech companies and I get a bigger cut much sooner.


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