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Ruth Sinaid: Amazon KDP author data
As of Nov 6, 2026, Ruth Sinaid has 3 books on Amazon, 3 of them on a best-seller list in the last 30 days (best rank #7), mostly in Astronomy, Solar System, Astronomy & Space Science.
| Median price | $3.99 |
|---|---|
| Price range (middle 50%) | $3.75 – $4.17 |
| Median reviews | - |
| Total reviews | 0 |
| New books (30 days) | 3 |
| Breakout books (30 days) | 2 |
What stands out
- Median price $3.99, 73% below the median of their main category, Astronomy.
- 3 new books in the last 30 days, 2 of them broke into a Best Sellers list.
Ruth Sinaid's best-ranked books
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VENUS: Earth’s Lost Twin: Inside the Hottest Planet, Its Mysterious Past, the Search for Life, and Humanity’s Future Above the Clouds
by Ruth Sinaid
- Price$4.35
- Reviews-
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Rocket Science for Beginners: A Simple Guide to Rockets, Spaceflight, Propulsion, and the History of Human Space Exploration
by Ruth Sinaid
- Price$3.99
- Reviews-
-
Pluto: Planet or Not?: The Strange, Surprising Story of the Solar System’s Most Debated World
by Ruth Sinaid
- Price$3.50
- Reviews-
Main categories
FAQ
How many books does Ruth Sinaid have on Amazon?
KDPTop tracks 3 of their books; 3 made an Amazon list in the last 30 days.
Which categories does Ruth Sinaid publish in?
Their books chart most often in Astronomy, Solar System, Astronomy & Space Science.
How does Ruth Sinaid price their books?
The median price is $3.99; half of the books cost $3.75–$4.17.
Has Ruth Sinaid released new books recently?
3 new books in the last 30 days, 2 of which reached a Best Sellers list.
About this data
Data comes from KDPTop's daily crawl of Amazon's public Best Sellers pages; medians use the latest list. The opportunity score (0–100, higher is easier to enter) combines the review barrier, the share of low-review books, list turnover, new-release share and price.