--- title: "Transit Backtests: Tiger Woods, Princess Diana and Trump" description: "Three retrospective tests of Vox Stella's transit scanner: Tiger Woods' 2021 accident, Princess Diana's 1997 crash and Trump's elections, with limits." url: "https://voxstella.app/blog/posts/validating-transit-predictions-tiger-woods-accident" --- Astrology # Transit Backtests: Tiger Woods (2021), Princess Diana (1997) and Trump's Election Days Three retrospective tests of the Vox Stella transit scanner against well-documented events, with the settings, the results, and the limits of what they show. Vox Stella Team • October 10, 2025 · Updated October 1, 2026 **In each of three backtests, the transit scanner's strongest signal fell on or near the known event.** All three were run after the fact on famous people, so they show how the scanner behaves on real timelines, not that it can predict events. We originally published these tests as three separate posts in October 2025. This page brings them together with one consistent description of the method and the caveats that apply to all of them. ## How the transit scanner works The Transit feature compares the sky at each step of a date range with a natal chart and scores what it finds. The score weights each contact by planetary speed, aspect type, orb, and house involvement, with extra weight for the angles; aspects are calculated with Morin-style spherical geometry, which accounts for planetary latitude. The results appear on a color-coded timeline (red bars where Mars and Saturn dominate, green where Jupiter and Venus dominate), with a list of top peaks, a positive or negative tone, and plain-language keywords for each peak. ## Backtest 1: Tiger Woods' accident, February 2021 On February 23, 2021, Tiger Woods was seriously injured in a single-vehicle rollover in Rolling Hills Estates, California; the 911 call was logged at 7:12 AM PST. His birth data (December 30, 1975, 10:50 PM, Long Beach, California) carries an AA Rodden rating, meaning it comes from a birth certificate or record. - **Settings:** scan February 1-23, 2021, daily steps, angular houses (1, 4, 7, 10) as sensitive points. - **Result:** the three highest negative scores in the window fell on February 21 (44.4), 22 (44.8), and 23 (44.8). The accident happened on the morning of February 23. - **Themes:** the auto-generated keywords for those days were "Injury risk", "Career strain", "Malefic", and "Negative", driven by applying hard aspects from Mars to the Midheaven and Saturn aspects to the angles. ![Transit timeline for Tiger Woods in February 2021, with the negative peak around February 21 to 23](../../assets/img/tigerwood.webp) The February 2021 scan, with the late-month negative cluster. **Caveat specific to this test:** the scan window ended on the accident date, so it cannot show whether the scores stayed high, or rose further, in the days after. ## Backtest 2: Princess Diana, August 1997 Diana, Princess of Wales, died after a car crash in Paris on August 31, 1997. We loaded her saved birth data and scanned **August 15 to September 15, 1997**. - **Result:** the timeline showed pronounced red spikes through late August, culminating in a tight cluster around August 30-31, the dates of the crash. - **Themes:** the peak carried a negative tone with the keywords *Travel* and *Body*. - **Also visible:** smaller earlier peaks, which a forward-looking user would have had no way to rank against the later one. ![Transit timeline highlighting the late-August 1997 cluster for Princess Diana](../../assets/img/diannascanner.webp) The August-September 1997 scan, with the August 30-31 cluster (negative tone; Travel and Body themes). ## Backtest 3: Donald Trump's election days This test compared two outcome-anchored windows for one chart (natal: June 14, 1946, 10:54 AM, New York): the presidential election he won in 2016 and the one he lost in 2020. - **Settings:** Regiomontanus houses; the seven classical planets; cusps and antiscia on; roughly one-month windows in October and November; 12-hour steps. - **Election he won:** day tag *Positive*, score about 53.4 from about 101 active contacts, led by career and public status (10th house) and friends and networks (11th). The timeline was red early in the window and turned greener toward the decision. - **Election he lost:** day tag *Negative*, score about 57.1 from about 117 contacts, led by friends and allies (11th), career (10th), money (2nd), and shared resources (8th). A green run before election night gave way to red and gray bars with tall negative spikes after it. ![Transit timeline around the 2016 election: predominantly positive bars late in the window](../../assets/img/trump-election-positive.webp) 2016 window: Positive day tag, with career (10th) and friends (11th) themes. ![Transit timeline around the 2020 election: negative spike cluster after election day](../../assets/img/trump-election-negative.webp) 2020 window: Negative rollup, with 10th- and 8th-house pressure. The scanner measures the transit climate for one chart; it does not forecast elections. Note also that the losing window scored higher overall: the tag reflects the balance of supportive and challenging contacts, not the size of the score. ## What these backtests do and do not show The tests are useful as demonstrations: they show that the scanner's scores and keywords respond to configurations around known events, and they document settings that anyone can rerun. They are not validation, because: - **They are retrospective.** The events, dates, and outcomes were known before each scan, and the windows were chosen around them. - **There is no baseline.** None of the tests compared the event window with ordinary periods for the same person, or with other people's charts on the same dates, so there is no way to say how unusual the peaks are. - **The sample is three famous people.** Choosing well-known, dramatic cases favors memorable matches; a fair test needs many cases chosen in advance, including events where nothing was flagged. - **Keywords invite matching.** Broad labels such as "Travel", "Body", or "Career strain" can fit many real events, and reading them after the fact makes a fit easy to find. Formal studies of astrology, such as Shawn Carlson's 1985 double-blind test published in *Nature*, have not supported astrological claims. Treat transit scores as a structured way to review a period, not as a forecast of events, and never as a reason to make safety, health, or financial decisions. ## Reproduce the Tiger Woods scan - Open the Transit feature. - Enter the natal data: December 30, 1975, 10:50 PM, Long Beach, California. - Set the scan window to February 1-23, 2021, with a step of 1,440 minutes (daily). - Choose the angular houses (1, 4, 7, 10) as sensitive points and run the scan. - Review the timeline and top peaks for February 20-23. Then extend the window past the event date to see what happens next. ## Using the transit scanner day to day - **Review a period:** scan a past month to see which contacts were active around milestones you remember. - **Plan ahead:** scan the next 30-90 days to see when supportive or challenging contacts cluster, then zoom in with a finer step. - **Read the breakdown:** every day tag can be opened to show the exact aspects, orbs, and phases behind the score. ## Sources - Birth data and Rodden ratings: Astro-Databank. - Event dates and times: contemporary news reports and public records of each event. - Jean-Baptiste Morin, *Astrologia Gallica* (1661), on which the aspect geometry is based. - Shawn Carlson, "A double-blind test of astrology", *Nature* 318 (1985): 419-425. ### Related Posts - [Blind Chart Reading Experiments: Can an AI Identify a Famous Chart?](/blog/posts/blind-chart-reading-experiment) - Astrology - [Iran–Israel–U.S. Conflict Timing: A 60-Day Mundane Astrology Experiment (August–October 2026)](/blog/posts/mundane-astrology-conflict-timing-experiment) - Research - [Astrological Trait Analysis Case Studies: Vincent van Gogh, Donald Trump and Benjamin Netanyahu](/blog/posts/astrological-trait-analysis-case-studies) - Astrology ```json { "@context": "https://schema.org", "@type": "Article", "headline": "Transit Backtests: Tiger Woods (2021), Princess Diana (1997) and Trump’s Election Days", "author": { "@type": "Organization", "name": "Vox Stella Team", "url": "https://voxstella.app" }, "publisher": { "@type": "Organization", "name": "Vox Stella", "logo": { "@type": "ImageObject", "url": "https://voxstella.app/assets/img/logo.ico" } }, "datePublished": "2025-10-10", "dateModified": "2026-10-01", "description": "Three retrospective tests of Vox Stella's transit scanner: Tiger Woods' 2021 accident, Princess Diana's 1997 crash and Trump's elections, with limits.", "image": "https://voxstella.app/assets/img/tigerwood.webp", "url": "https://voxstella.app/blog/posts/validating-transit-predictions-tiger-woods-accident", "mainEntityOfPage": { "@type": "WebPage", "@id": "https://voxstella.app/blog/posts/validating-transit-predictions-tiger-woods-accident" }, "articleSection": "Astrology", "inLanguage": "en" } { "@context": "https://schema.org", "@type": "BreadcrumbList", "itemListElement": [ { "@type": "ListItem", "position": 1, "name": "Home", "item": "https://voxstella.app/" }, { "@type": "ListItem", "position": 2, "name": "Blog", "item": "https://voxstella.app/blog" }, { "@type": "ListItem", "position": 3, "name": "Transit Backtests", "item": "https://voxstella.app/blog/posts/validating-transit-predictions-tiger-woods-accident" } ] } ```