Astronomy & Space Science — Kindle Category Opportunity
Competition snapshot for the Science & Math best-seller list, ease-of-entry score 47.5/100.
Category metrics
Score
47.5
Median reviews
472.5
Weak share (top 20)
35%
Median price
$9.14
Median star rating
4.6
Books scanned
50
Worth writing in?
Observation companions and night-sky logbooks fit a data-driven workflow: celestial tables are computable, and annual editions create repeat buyers. The core astronomy subcategory sustains solid demand at mid-range prices while staying reference-shaped rather than narrative.
Editor's note.
Breakout books — top 15, under 100 reviews, $0.99–4.99
Best-seller list on AmazonNo breakout books in this category.
High-frequency phrases in this category's titles
Mine all categoriesHigh-frequency phrases mined from the 50 best-seller titles on this category's list. The ease-of-entry score tells you how winnable the category is; these title phrases tell you which words readers search with — use the two layers together. Frequency is a title statistic, not a search-volume estimate.
| Phrase | Titles | Rank-weighted score |
|---|---|---|
| scientific american | 3 | 125 |
| lessons on physics | 2 | 68 |
| brief history | 2 | 45 |
| end of time | 2 | 41 |
| ufo program | 2 | 36 |
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More Science & Math categories
8 subcategories under this category
| Subcategory | Score | Median reviews |
|---|---|---|
| █████ | 81.5 | 1 |
| █████ | 73.5 | 2.5 |
| █████ | 63.0 | 16.5 |
| █████ | 58.0 | 574.5 |
| █████ | 53.5 | 616.5 |
| █████ | 52.0 | 223 |
| █████ | 46.0 | 251 |
| █████ | 38.5 | 349 |
Subcategory names are visible after sign-in — a free account unlocks every subcategory score.
Sign up free to unlockCheck the keywords before you write
Category scores show where entry is easiest; keyword lookups show whether readers actually reach for it. A free account includes keyword competition lookups plus unlimited category scans.
After you publish: why aren't readers buying?
Category research picks the direction; review diagnosis reads the readers. The same platform clusters a book's critical reviews into severity-ranked root causes, each anchored to verbatim quotes — see it applied to a full narrative-history title.
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Research snapshot scanned on Oct 19, 2026. Refreshed periodically — not live tracking.