Mercury Combust AND Retrograde: We Tested the Double Condition on 76 Years of Data
The logic sounds airtight: if Mercury retrograde scrambles markets and combustion “burns up” Mercury's signal, then the stretch where both hold should be the real danger zone. The 2008 crash week and the COVID crash both started inside one. So we computed the combust-retrograde window of all 242 retrogrades since 1950 and put the S&P 500 through the full battery — drops after entering it, volatility and returns inside it, a chart for every single one.
The Conclusion
The market cannot tell when Mercury is combust and retrograde. Drops after entering the double condition run below the any-day base rate at nearly every threshold, and the 1,401 trading days inside the windows are statistically identical to the 17,800 outside them — same volatility, same share of up days, same everything.
The double condition isn't rare — it's guaranteed. Mercury stations 15–22° from the Sun and falls back inside the 8.5° combustion orb about a week later, in every retrograde. The window lasts 7–12 days, centered on the inferior conjunction. Three times a year, like clockwork.
Entering it predicts nothing. A 2% closing drop followed within five days 15.8% of the time, against an 18.2% base rate. Wicks: 24.5% vs. 26.6%. Seven of eight threshold/measure combinations sit below their base rates.
Life inside the window is indistinguishable. Average daily range 1.19% inside vs. 1.17% outside; 31.3% of days with a 1.5%+ range vs. 31.2%; 53.2% up days vs. 53.1%. If Mercury's signal were being burned up, the tape never noticed.
The anchors are the 2008 and 2020 crashes. The window that opened October 3, 2008 preceded an 18.2% five-day collapse; the February 22, 2020 window opened days before COVID hit the tape. Two unforgettable weeks — and 2 of 242 windows.
Everything below is how we got there — the astronomy, the definitions, the base rates, and an interactive table of all 242 combust-retrograde windows where you can open the chart for every one and check us.
The Claim
In traditional astrology a planet is combust when it sits within about 8.5° of the Sun — overwhelmed, weakened, its significations “burned up.” Mercury rules communication, contracts, and commerce; retrograde already marks those as unreliable. Stack the two — Mercury combust and retrograde — and the astro-trading logic says you have maximum signal failure: the stretch when misinformation peaks, deals break, and markets should stumble.
The highlight reel cooperates. The S&P 500's worst week of the 2008 financial crisis began the day Mercury's October 2008 retrograde turned combust. The COVID crash of February 2020 started inside another such window. Checkable claim, memorable anchors — all it is missing is the control group.
First, the Astronomy: the Double Condition Is Guaranteed
Here is the part the “rare double whammy” framing skips: every Mercury retrograde contains a combust stretch, by construction. Mercury stations retrograde 15–22° from the Sun — outside the orb — then falls back toward it, crossing inside 8.5° a median of 7 days after the station. It passes the inferior conjunction (the cazimi, the retrograde's midpoint), exits the orb, and stations direct outside it again. Across all 242 retrogrades since 1950 the combust-retrograde window lasted 7 to 12 days, median 8.
So the double condition is not a special alignment — it is the ordinary middle third of every retrograde, arriving three times a year. That makes it easy to test honestly: 242 entry dates, 1,401 trading days inside the windows, and 76 years of S&P 500 data to check them against.
Test 1: Does Entering the Window Precede Drops?
For each retrograde we took the first day Mercury was both retrograde and combust, snapped it to the nearest trading day, and measured the worst move against that day's close over the next five trading days — by lowest close and by lowest intraday wick — at four thresholds. The control, as always: what share of all 19,252 trading days pass the same test?
| Drop within 5 days | Base rate (close) | After entry (close) | Base rate (wick) | After entry (wick) |
|---|---|---|---|---|
| ≥1% | 36.9% | 35.3% | 50.2% | 44.0% |
| ≥1.5% | 26.3% | 24.5% | 36.5% | 35.3% |
| ≥2% | 18.2% | 15.8% | 26.6% | 24.5% |
| ≥3% | 8.7% | 9.1% | 13.6% | 12.9% |
Seven of eight cells sit below their base rate; the eighth (3% closing drops, 9.1% vs. 8.7%) is one extra hit in 76 years. The best p-value in the grid is 0.45. If anything, the week after Mercury's signal “burns up” has been slightly calmer than a random week.
Test 2: Is It Chaos Inside the Window?
Maybe the claim isn't about what follows the window but about what happens during it — whipsaws, fake-outs, big ranges. That is measurable too. Since 1950 there have been 1,401 trading days with Mercury combust and retrograde. Here they are against the other ~17,800:
1.19% vs 1.17%
Avg daily high–low range, inside vs. outside
31.3% vs 31.2%
Days with a 1.5%+ range, inside vs. outside
53.2% vs 53.1%
Up days, inside vs. outside
No test separates the two populations (volatility p = 0.55, returns p = 0.87). Average daily drift inside the windows is +0.016% vs. +0.038% outside — a difference that is pure noise at this sample size — and the typical whole-window return is +0.11% with 57% of windows closing higher, against +0.22% and the same 57% for random stretches of equal length. Whatever Mercury's combustion burns, it is not the order book.
Check Every Window Yourself: All 242 Since 1950
Don't take the aggregates on faith. Below is every combust-retrograde window since 1950 with the worst five-day move after entering it, a closes/wicks toggle, and the return across the window itself. Click any entry date to open the chart. October 2008 and February 2020 are in there — and so are 240 windows the market sailed through.
241
Combust-retro entries 1950–2026
38 (15.8%)
With a 2% drop in the next 5 days
18.2%
Random-day base rate
Entry = the first day Mercury is both retrograde and inside the 8.5° combustion orb. “Next 5 days” is the worst move vs. the entry day's close, by lowest close or lowest intraday wick (red = fell 2% or more). “Window” is the close-to-close return across the whole combust-retrograde stretch. Click an entry date to open the chart.
| Combust + retro | Retrograde | Next 5 days | Window |
|---|---|---|---|
| Jul 8, 2026 – Jul 17, 2026 | Jun 29, 2026 – Jul 23, 2026 | not enough data yet | not enough data yet |
| Mar 3, 2026 – Mar 10, 2026 | Feb 26, 2026 – Mar 20, 2026 | -1.1% | -1.5% |
| Nov 17, 2025 – Nov 23, 2025 | Nov 9, 2025 – Nov 29, 2025 | -2.0% | -0.4% |
| Jul 28, 2025 – Aug 4, 2025 | Jul 18, 2025 – Aug 11, 2025 | -2.4% | -0.9% |
| Mar 20, 2025 – Mar 28, 2025 | Mar 15, 2025 – Apr 7, 2025 | +0.1% | -1.7% |
| Dec 2, 2024 – Dec 9, 2024 | Nov 26, 2024 – Dec 15, 2024 | +0.1% | +0.3% |
| Aug 15, 2024 – Aug 23, 2024 | Aug 5, 2024 – Aug 28, 2024 | +0.2% | +3.3% |
| Apr 7, 2024 – Apr 16, 2024 | Apr 1, 2024 – Apr 25, 2024 | -2.7% | -2.9% |
| Dec 19, 2023 – Dec 25, 2023 | Dec 13, 2023 – Jan 2, 2024 | -1.5% | +0.7% |
| Sep 3, 2023 – Sep 10, 2023 | Aug 23, 2023 – Sep 15, 2023 | -1.4% | -0.5% |
| Apr 27, 2023 – May 6, 2023 | Apr 21, 2023 – May 15, 2023 | -1.8% | +2.0% |
| Jan 4, 2023 – Jan 10, 2023 | Dec 29, 2022 – Jan 18, 2023 | -1.2% | +2.5% |
| Sep 20, 2022 – Sep 27, 2022 | Sep 10, 2022 – Oct 2, 2022 | -5.4% | -6.5% |
| May 16, 2022 – May 26, 2022 | May 10, 2022 – Jun 3, 2022 | -2.7% | +0.8% |
| Jan 20, 2022 – Jan 26, 2022 | Jan 14, 2022 – Feb 4, 2022 | -3.5% | -4.0% |
| Oct 6, 2021 – Oct 13, 2021 | Sep 27, 2021 – Oct 18, 2021 | -0.3% | +0.4% |
| Jun 5, 2021 – Jun 15, 2021 | May 29, 2021 – Jun 22, 2021 | -0.2% | +1.3% |
| Feb 5, 2021 – Feb 11, 2021 | Jan 30, 2021 – Feb 20, 2021 | +0.6% | +1.1% |
| Oct 22, 2020 – Oct 29, 2020 | Oct 13, 2020 – Nov 3, 2020 | -5.3% | -3.6% |
| Jun 26, 2020 – Jul 5, 2020 | Jun 18, 2020 – Jul 12, 2020 | +1.5% | +3.1% |
| Feb 22, 2020 – Feb 29, 2020 | Feb 16, 2020 – Mar 10, 2020 | -11.5% | -12.4% |
| Nov 8, 2019 – Nov 14, 2019 | Oct 31, 2019 – Nov 20, 2019 | -0.2% | +0.4% |
| Jul 17, 2019 – Jul 25, 2019 | Jul 7, 2019 – Aug 1, 2019 | -0.3% | -0.0% |
| Mar 11, 2019 – Mar 18, 2019 | Mar 5, 2019 – Mar 28, 2019 | +0.3% | +3.3% |
| Nov 24, 2018 – Nov 30, 2018 | Nov 16, 2018 – Dec 6, 2018 | +1.6% | +4.2% |
| Aug 5, 2018 – Aug 13, 2018 | Jul 26, 2018 – Aug 19, 2018 | -1.0% | -0.7% |
| Mar 28, 2018 – Apr 5, 2018 | Mar 22, 2018 – Apr 15, 2018 | -0.9% | +1.9% |
| Dec 9, 2017 – Dec 16, 2017 | Dec 3, 2017 – Dec 22, 2017 | +0.0% | +1.5% |
| Aug 23, 2017 – Aug 30, 2017 | Aug 12, 2017 – Sep 5, 2017 | -0.2% | +0.2% |
| Apr 15, 2017 – Apr 24, 2017 | Apr 9, 2017 – May 3, 2017 | +0.4% | +1.3% |
| Dec 25, 2016 – Dec 31, 2016 | Dec 19, 2016 – Jan 8, 2017 | -1.1% | -1.0% |
| Sep 9, 2016 – Sep 16, 2016 | Aug 30, 2016 – Sep 22, 2016 | -0.1% | -1.9% |
| May 4, 2016 – May 14, 2016 | Apr 28, 2016 – May 22, 2016 | -0.0% | -0.8% |
| Jan 11, 2016 – Jan 17, 2016 | Jan 5, 2016 – Jan 25, 2016 | -2.3% | -2.2% |
| Sep 27, 2015 – Oct 4, 2015 | Sep 17, 2015 – Oct 9, 2015 | +0.1% | +2.9% |
| May 25, 2015 – Jun 4, 2015 | May 19, 2015 – Jun 11, 2015 | +0.1% | -1.4% |
| Jan 27, 2015 – Feb 2, 2015 | Jan 21, 2015 – Feb 11, 2015 | -1.7% | -1.8% |
| Oct 13, 2014 – Oct 20, 2014 | Oct 4, 2014 – Oct 25, 2014 | -0.7% | -0.1% |
| Jun 14, 2014 – Jun 24, 2014 | Jun 7, 2014 – Jul 1, 2014 | +0.1% | +1.0% |
| Feb 12, 2014 – Feb 18, 2014 | Feb 6, 2014 – Feb 28, 2014 | +0.5% | +1.1% |
| Oct 29, 2013 – Nov 5, 2013 | Oct 21, 2013 – Nov 10, 2013 | -0.9% | +0.1% |
| Jul 5, 2013 – Jul 13, 2013 | Jun 26, 2013 – Jul 20, 2013 | +0.5% | +4.0% |
| Mar 1, 2013 – Mar 7, 2013 | Feb 23, 2013 – Mar 17, 2013 | +0.5% | +1.9% |
| Nov 14, 2012 – Nov 20, 2012 | Nov 6, 2012 – Nov 26, 2012 | -0.2% | +1.0% |
| Jul 25, 2012 – Aug 1, 2012 | Jul 15, 2012 – Aug 8, 2012 | +1.6% | +2.8% |
| Mar 18, 2012 – Mar 25, 2012 | Mar 12, 2012 – Apr 4, 2012 | -1.2% | +0.9% |
| Dec 1, 2011 – Dec 7, 2011 | Nov 24, 2011 – Dec 13, 2011 | -0.8% | +1.1% |
| Aug 13, 2011 – Aug 21, 2011 | Aug 3, 2011 – Aug 26, 2011 | -4.7% | -4.2% |
| Apr 5, 2011 – Apr 14, 2011 | Mar 30, 2011 – Apr 23, 2011 | -1.4% | -1.4% |
| Dec 16, 2010 – Dec 23, 2010 | Dec 10, 2010 – Dec 30, 2010 | +0.1% | +1.7% |
| Aug 31, 2010 – Sep 7, 2010 | Aug 20, 2010 – Sep 12, 2010 | +3.0% | +4.1% |
| Apr 23, 2010 – May 3, 2010 | Apr 18, 2010 – May 11, 2010 | -2.8% | -0.5% |
| Jan 1, 2010 – Jan 7, 2010 | Dec 26, 2009 – Jan 15, 2010 | +1.6% | +1.4% |
| Sep 17, 2009 – Sep 24, 2009 | Sep 7, 2009 – Sep 29, 2009 | -1.4% | -1.7% |
| May 13, 2009 – May 23, 2009 | May 7, 2009 – May 30, 2009 | -0.1% | -2.4% |
| Jan 17, 2009 – Jan 23, 2009 | Jan 11, 2009 – Feb 1, 2009 | -5.3% | -1.4% |
| Oct 3, 2008 – Oct 10, 2008 | Sep 24, 2008 – Oct 15, 2008 | -18.2% | -19.3% |
| Jun 2, 2008 – Jun 12, 2008 | May 26, 2008 – Jun 19, 2008 | -1.8% | -4.3% |
| Feb 3, 2008 – Feb 9, 2008 | Jan 28, 2008 – Feb 19, 2008 | -3.9% | -4.6% |
| Oct 20, 2007 – Oct 27, 2007 | Oct 12, 2007 – Nov 1, 2007 | +0.4% | -0.3% |
| Jun 24, 2007 – Jul 2, 2007 | Jun 15, 2007 – Jul 10, 2007 | -0.3% | +1.1% |
| Feb 19, 2007 – Feb 26, 2007 | Feb 14, 2007 – Mar 8, 2007 | -4.2% | -0.4% |
| Nov 5, 2006 – Nov 12, 2006 | Oct 28, 2006 – Nov 17, 2006 | -0.1% | +1.5% |
| Jul 14, 2006 – Jul 22, 2006 | Jul 4, 2006 – Jul 28, 2006 | -0.1% | -0.2% |
| Mar 8, 2006 – Mar 15, 2006 | Mar 2, 2006 – Mar 25, 2006 | -0.5% | +2.1% |
| Nov 21, 2005 – Nov 27, 2005 | Nov 14, 2005 – Dec 3, 2005 | +0.2% | +0.7% |
| Aug 2, 2005 – Aug 9, 2005 | Jul 23, 2005 – Aug 16, 2005 | -1.7% | -0.3% |
| Mar 25, 2005 – Apr 2, 2005 | Mar 19, 2005 – Apr 12, 2005 | -0.5% | +0.0% |
| Dec 7, 2004 – Dec 13, 2004 | Nov 30, 2004 – Dec 20, 2004 | +0.5% | +0.7% |
| Aug 20, 2004 – Aug 27, 2004 | Aug 9, 2004 – Sep 2, 2004 | -0.2% | +1.5% |
| Apr 12, 2004 – Apr 21, 2004 | Apr 6, 2004 – Apr 30, 2004 | -1.5% | -1.3% |
| Dec 23, 2003 – Dec 29, 2003 | Dec 17, 2003 – Jan 6, 2004 | -0.2% | +1.5% |
| Sep 7, 2003 – Sep 14, 2003 | Aug 28, 2003 – Sep 20, 2003 | -2.0% | -0.6% |
| May 2, 2003 – May 12, 2003 | Apr 26, 2003 – May 20, 2003 | -1.1% | +3.1% |
| Jan 8, 2003 – Jan 14, 2003 | Jan 2, 2003 – Jan 22, 2003 | +0.9% | +0.9% |
| Sep 24, 2002 – Oct 1, 2002 | Sep 14, 2002 – Oct 6, 2002 | -0.5% | +1.7% |
| May 22, 2002 – Jun 1, 2002 | May 15, 2002 – Jun 8, 2002 | -2.0% | -1.2% |
| Jan 24, 2002 – Jan 30, 2002 | Jan 18, 2002 – Feb 8, 2002 | -2.8% | -1.3% |
| Oct 10, 2001 – Oct 17, 2001 | Oct 1, 2001 – Oct 22, 2001 | -0.4% | +1.9% |
| Jun 11, 2001 – Jun 21, 2001 | Jun 4, 2001 – Jun 28, 2001 | -3.7% | -2.2% |
| Feb 9, 2001 – Feb 16, 2001 | Feb 3, 2001 – Feb 25, 2001 | -1.0% | -2.3% |
| Oct 26, 2000 – Nov 2, 2000 | Oct 18, 2000 – Nov 8, 2000 | +1.1% | +4.7% |
| Jul 2, 2000 – Jul 10, 2000 | Jun 23, 2000 – Jul 17, 2000 | -1.6% | +1.4% |
| Feb 27, 2000 – Mar 5, 2000 | Feb 21, 2000 – Mar 14, 2000 | +1.4% | +4.3% |
| Nov 12, 1999 – Nov 19, 1999 | Nov 5, 1999 – Nov 25, 1999 | -0.1% | +2.9% |
| Jul 22, 1999 – Jul 30, 1999 | Jul 12, 1999 – Aug 6, 1999 | -1.5% | -3.7% |
| Mar 16, 1999 – Mar 23, 1999 | Mar 10, 1999 – Apr 2, 1999 | -3.4% | -3.5% |
| Nov 28, 1998 – Dec 4, 1998 | Nov 21, 1998 – Dec 11, 1998 | -3.5% | -0.8% |
| Aug 10, 1998 – Aug 17, 1998 | Jul 31, 1998 – Aug 23, 1998 | -1.9% | -0.5% |
| Apr 2, 1998 – Apr 10, 1998 | Mar 27, 1998 – Apr 20, 1998 | -1.6% | +0.2% |
| Dec 14, 1997 – Dec 20, 1997 | Dec 7, 1997 – Dec 27, 1997 | -1.7% | -0.7% |
| Aug 28, 1997 – Sep 4, 1997 | Aug 17, 1997 – Sep 10, 1997 | -0.5% | +1.9% |
| Apr 20, 1997 – Apr 30, 1997 | Apr 14, 1997 – May 8, 1997 | +0.7% | +4.6% |
| Dec 29, 1996 – Jan 4, 1997 | Dec 23, 1996 – Jan 12, 1997 | -2.2% | -1.2% |
| Sep 14, 1996 – Sep 21, 1996 | Sep 4, 1996 – Sep 26, 1996 | +0.1% | +2.4% |
| May 9, 1996 – May 19, 1996 | May 3, 1996 – May 27, 1996 | +1.0% | +4.4% |
| Jan 15, 1996 – Jan 21, 1996 | Jan 9, 1996 – Jan 30, 1996 | +1.1% | +1.9% |
| Oct 1, 1995 – Oct 8, 1995 | Sep 22, 1995 – Oct 13, 1995 | -0.6% | -1.0% |
| May 30, 1995 – Jun 9, 1995 | May 24, 1995 – Jun 17, 1995 | +1.7% | +0.8% |
| Jan 31, 1995 – Feb 6, 1995 | Jan 25, 1995 – Feb 16, 1995 | 0.0% | +2.7% |
| Oct 17, 1994 – Oct 24, 1994 | Oct 9, 1994 – Oct 30, 1994 | -1.7% | -1.8% |
| Jun 20, 1994 – Jun 29, 1994 | Jun 12, 1994 – Jul 6, 1994 | -2.8% | -2.4% |
| Feb 16, 1994 – Feb 23, 1994 | Feb 11, 1994 – Mar 5, 1994 | -1.8% | -0.4% |
| Nov 2, 1993 – Nov 9, 1993 | Oct 25, 1993 – Nov 15, 1993 | -2.3% | -1.9% |
| Jul 10, 1993 – Jul 19, 1993 | Jul 1, 1993 – Jul 25, 1993 | -0.5% | -0.6% |
| Mar 5, 1993 – Mar 12, 1993 | Feb 27, 1993 – Mar 22, 1993 | +0.8% | +0.6% |
| Nov 18, 1992 – Nov 25, 1992 | Nov 11, 1992 – Dec 1, 1992 | +0.2% | +2.4% |
| Jul 30, 1992 – Aug 6, 1992 | Jul 19, 1992 – Aug 13, 1992 | -0.8% | -0.4% |
| Mar 22, 1992 – Mar 30, 1992 | Mar 16, 1992 – Apr 9, 1992 | -1.7% | -2.0% |
| Dec 5, 1991 – Dec 11, 1991 | Nov 28, 1991 – Dec 18, 1991 | +0.1% | -0.6% |
| Aug 18, 1991 – Aug 25, 1991 | Aug 7, 1991 – Aug 31, 1991 | +0.8% | +2.1% |
| Apr 10, 1991 – Apr 19, 1991 | Apr 4, 1991 – Apr 28, 1991 | +1.2% | +2.9% |
| Dec 21, 1990 – Dec 27, 1990 | Dec 14, 1990 – Jan 3, 1991 | -1.0% | -0.6% |
| Sep 4, 1990 – Sep 12, 1990 | Aug 25, 1990 – Sep 17, 1990 | -0.8% | -0.0% |
| Apr 29, 1990 – May 8, 1990 | Apr 23, 1990 – May 17, 1990 | +0.4% | +3.9% |
| Jan 5, 1990 – Jan 11, 1990 | Dec 30, 1989 – Jan 20, 1990 | -3.5% | -2.0% |
| Sep 21, 1989 – Sep 28, 1989 | Sep 11, 1989 – Oct 3, 1989 | -0.4% | +0.6% |
| May 18, 1989 – May 28, 1989 | May 12, 1989 – Jun 5, 1989 | +0.1% | +1.3% |
| Jan 21, 1989 – Jan 27, 1989 | Jan 15, 1989 – Feb 5, 1989 | -0.7% | +2.4% |
| Oct 8, 1988 – Oct 14, 1988 | Sep 28, 1988 – Oct 20, 1988 | -1.5% | +1.1% |
| Jun 8, 1988 – Jun 17, 1988 | May 31, 1988 – Jun 24, 1988 | -0.5% | +2.1% |
| Feb 7, 1988 – Feb 14, 1988 | Feb 2, 1988 – Feb 23, 1988 | +1.1% | +2.7% |
| Oct 25, 1987 – Oct 31, 1987 | Oct 16, 1987 – Nov 6, 1987 | +2.4% | +1.4% |
| Jun 29, 1987 – Jul 8, 1987 | Jun 21, 1987 – Jul 15, 1987 | -1.6% | +0.4% |
| Feb 24, 1987 – Mar 3, 1987 | Feb 18, 1987 – Mar 12, 1987 | +0.0% | +0.6% |
| Nov 9, 1986 – Nov 16, 1986 | Nov 2, 1986 – Nov 22, 1986 | -1.3% | -1.0% |
| Jul 19, 1986 – Jul 27, 1986 | Jul 9, 1986 – Aug 2, 1986 | -0.1% | -0.0% |
| Mar 13, 1986 – Mar 20, 1986 | Mar 7, 1986 – Mar 30, 1986 | +0.6% | +1.7% |
| Nov 25, 1985 – Dec 2, 1985 | Nov 18, 1985 – Dec 8, 1985 | +0.1% | -0.5% |
| Aug 7, 1985 – Aug 14, 1985 | Jul 27, 1985 – Aug 20, 1985 | -0.2% | -0.3% |
| Mar 30, 1985 – Apr 7, 1985 | Mar 24, 1985 – Apr 17, 1985 | -1.5% | -0.8% |
| Dec 11, 1984 – Dec 17, 1984 | Dec 4, 1984 – Dec 24, 1984 | -0.8% | +0.5% |
| Aug 25, 1984 – Sep 1, 1984 | Aug 14, 1984 – Sep 7, 1984 | -0.6% | -0.3% |
| Apr 17, 1984 – Apr 26, 1984 | Apr 11, 1984 – May 5, 1984 | -1.4% | +1.3% |
| Dec 28, 1983 – Jan 3, 1984 | Dec 21, 1983 – Jan 10, 1984 | -0.8% | -0.4% |
| Sep 12, 1983 – Sep 19, 1983 | Sep 2, 1983 – Sep 24, 1983 | -0.7% | +0.4% |
| May 7, 1983 – May 17, 1983 | May 1, 1983 – May 25, 1983 | -1.1% | -0.3% |
| Jan 12, 1983 – Jan 19, 1983 | Jan 7, 1983 – Jan 27, 1983 | -1.0% | -0.3% |
| Sep 28, 1982 – Oct 5, 1982 | Sep 19, 1982 – Oct 11, 1982 | -2.3% | -1.3% |
| May 27, 1982 – Jun 6, 1982 | May 21, 1982 – Jun 13, 1982 | -2.3% | -2.6% |
| Jan 28, 1982 – Feb 4, 1982 | Jan 23, 1982 – Feb 13, 1982 | -2.1% | +0.6% |
| Oct 15, 1981 – Oct 21, 1981 | Oct 6, 1981 – Oct 27, 1981 | -0.6% | +1.1% |
| Jun 17, 1981 – Jun 26, 1981 | Jun 9, 1981 – Jul 3, 1981 | -1.3% | +0.3% |
| Feb 14, 1981 – Feb 20, 1981 | Feb 8, 1981 – Mar 2, 1981 | -0.3% | -0.7% |
| Oct 31, 1980 – Nov 6, 1980 | Oct 23, 1980 – Nov 12, 1980 | +1.1% | +2.1% |
| Jul 7, 1980 – Jul 15, 1980 | Jun 28, 1980 – Jul 22, 1980 | -1.1% | +1.6% |
| Mar 2, 1980 – Mar 9, 1980 | Feb 25, 1980 – Mar 19, 1980 | -5.3% | -6.3% |
| Nov 16, 1979 – Nov 23, 1979 | Nov 9, 1979 – Nov 29, 1979 | -0.1% | +0.5% |
| Jul 28, 1979 – Aug 4, 1979 | Jul 17, 1979 – Aug 11, 1979 | +0.1% | +0.9% |
| Mar 20, 1979 – Mar 28, 1979 | Mar 14, 1979 – Apr 7, 1979 | +0.5% | +1.1% |
| Dec 2, 1978 – Dec 8, 1978 | Nov 25, 1978 – Dec 15, 1978 | -0.1% | +2.0% |
| Aug 15, 1978 – Aug 22, 1978 | Aug 4, 1978 – Aug 28, 1978 | +0.0% | +0.3% |
| Apr 7, 1978 – Apr 16, 1978 | Apr 1, 1978 – Apr 25, 1978 | -0.1% | +5.2% |
| Dec 18, 1977 – Dec 24, 1977 | Dec 11, 1977 – Dec 31, 1977 | -0.2% | +1.4% |
| Sep 1, 1977 – Sep 9, 1977 | Aug 22, 1977 – Sep 14, 1977 | -0.5% | -0.4% |
| Apr 25, 1977 – May 5, 1977 | Apr 19, 1977 – May 13, 1977 | -0.0% | +1.7% |
| Jan 3, 1977 – Jan 9, 1977 | Dec 28, 1976 – Jan 17, 1977 | -2.1% | -2.1% |
| Sep 18, 1976 – Sep 25, 1976 | Sep 8, 1976 – Oct 1, 1976 | +0.1% | +1.4% |
| May 15, 1976 – May 25, 1976 | May 9, 1976 – Jun 1, 1976 | -0.3% | -2.6% |
| Jan 20, 1976 – Jan 26, 1976 | Jan 14, 1976 – Feb 3, 1976 | -0.8% | +1.4% |
| Oct 6, 1975 – Oct 13, 1975 | Sep 26, 1975 – Oct 18, 1975 | -0.1% | +4.1% |
| Jun 5, 1975 – Jun 15, 1975 | May 29, 1975 – Jun 22, 1975 | -2.8% | -1.2% |
| Feb 5, 1975 – Feb 11, 1975 | Jan 30, 1975 – Feb 20, 1975 | -0.8% | +1.3% |
| Oct 22, 1974 – Oct 29, 1974 | Oct 13, 1974 – Nov 3, 1974 | -4.2% | -0.9% |
| Jun 26, 1974 – Jul 5, 1974 | Jun 17, 1974 – Jul 12, 1974 | -3.8% | -6.0% |
| Feb 21, 1974 – Feb 28, 1974 | Feb 15, 1974 – Mar 9, 1974 | +0.3% | +3.0% |
| Nov 7, 1973 – Nov 13, 1973 | Oct 30, 1973 – Nov 19, 1973 | -3.2% | -0.6% |
| Jul 16, 1973 – Jul 24, 1973 | Jul 6, 1973 – Jul 30, 1973 | +0.1% | +3.9% |
| Mar 10, 1973 – Mar 17, 1973 | Mar 4, 1973 – Mar 27, 1973 | -0.2% | -0.6% |
| Nov 22, 1972 – Nov 29, 1972 | Nov 15, 1972 – Dec 5, 1972 | -0.4% | +0.3% |
| Aug 4, 1972 – Aug 11, 1972 | Jul 24, 1972 – Aug 17, 1972 | +0.2% | +1.6% |
| Mar 27, 1972 – Apr 4, 1972 | Mar 21, 1972 – Apr 14, 1972 | -0.8% | +0.6% |
| Dec 9, 1971 – Dec 15, 1971 | Dec 2, 1971 – Dec 22, 1971 | +0.7% | +1.7% |
| Aug 23, 1971 – Aug 30, 1971 | Aug 12, 1971 – Sep 5, 1971 | +0.3% | +1.2% |
| Apr 15, 1971 – Apr 24, 1971 | Apr 9, 1971 – May 3, 1971 | -0.1% | +0.7% |
| Dec 25, 1970 – Dec 31, 1970 | Dec 19, 1970 – Jan 8, 1971 | +0.5% | +2.3% |
| Sep 9, 1970 – Sep 16, 1970 | Aug 30, 1970 – Sep 21, 1970 | -1.7% | -1.5% |
| May 4, 1970 – May 14, 1970 | Apr 28, 1970 – May 22, 1970 | -1.0% | -7.4% |
| Jan 10, 1970 – Jan 16, 1970 | Jan 4, 1970 – Jan 24, 1970 | -1.6% | -1.9% |
| Sep 26, 1969 – Oct 3, 1969 | Sep 16, 1969 – Oct 8, 1969 | -1.7% | -1.7% |
| May 24, 1969 – Jun 3, 1969 | May 17, 1969 – Jun 10, 1969 | -1.6% | -1.9% |
| Jan 26, 1969 – Feb 1, 1969 | Jan 20, 1969 – Feb 10, 1969 | +0.0% | +0.6% |
| Oct 12, 1968 – Oct 19, 1968 | Oct 3, 1968 – Oct 24, 1968 | +0.1% | +1.5% |
| Jun 13, 1968 – Jun 23, 1968 | Jun 6, 1968 – Jun 30, 1968 | -1.2% | -1.3% |
| Feb 12, 1968 – Feb 18, 1968 | Feb 6, 1968 – Feb 28, 1968 | +1.0% | +0.5% |
| Oct 29, 1967 – Nov 5, 1967 | Oct 21, 1967 – Nov 10, 1967 | -3.5% | -3.7% |
| Jul 5, 1967 – Jul 13, 1967 | Jun 26, 1967 – Jul 20, 1967 | -0.0% | +1.7% |
| Feb 28, 1967 – Mar 7, 1967 | Feb 23, 1967 – Mar 17, 1967 | +1.0% | +2.0% |
| Nov 14, 1966 – Nov 20, 1966 | Nov 6, 1966 – Nov 26, 1966 | -1.6% | -2.3% |
| Jul 24, 1966 – Aug 1, 1966 | Jul 14, 1966 – Aug 7, 1966 | -1.8% | -3.6% |
| Mar 17, 1966 – Mar 25, 1966 | Mar 11, 1966 – Apr 4, 1966 | +0.4% | +1.9% |
| Nov 29, 1965 – Dec 6, 1965 | Nov 22, 1965 – Dec 12, 1965 | -1.3% | -1.6% |
| Aug 12, 1965 – Aug 19, 1965 | Aug 1, 1965 – Aug 25, 1965 | +0.5% | +0.8% |
| Apr 4, 1965 – Apr 12, 1965 | Mar 29, 1965 – Apr 22, 1965 | -0.0% | +1.6% |
| Dec 15, 1964 – Dec 21, 1964 | Dec 9, 1964 – Dec 28, 1964 | +0.4% | +1.1% |
| Aug 29, 1964 – Sep 6, 1964 | Aug 19, 1964 – Sep 11, 1964 | -0.2% | +1.3% |
| Apr 22, 1964 – May 2, 1964 | Apr 16, 1964 – May 10, 1964 | -1.4% | -0.5% |
| Jan 1, 1964 – Jan 7, 1964 | Dec 26, 1963 – Jan 15, 1964 | +0.6% | +1.5% |
| Sep 16, 1963 – Sep 24, 1963 | Sep 6, 1963 – Sep 29, 1963 | -0.4% | +0.2% |
| May 12, 1963 – May 23, 1963 | May 6, 1963 – May 30, 1963 | -0.7% | -0.6% |
| Jan 17, 1963 – Jan 23, 1963 | Jan 11, 1963 – Jan 31, 1963 | +0.1% | +1.5% |
| Oct 3, 1962 – Oct 10, 1962 | Sep 24, 1962 – Oct 15, 1962 | +1.0% | +2.0% |
| Jun 2, 1962 – Jun 11, 1962 | May 26, 1962 – Jun 19, 1962 | -3.5% | -3.0% |
| Feb 2, 1962 – Feb 8, 1962 | Jan 27, 1962 – Feb 17, 1962 | +0.1% | +1.9% |
| Oct 19, 1961 – Oct 26, 1961 | Oct 10, 1961 – Oct 31, 1961 | -0.7% | +0.4% |
| Jun 22, 1961 – Jul 1, 1961 | Jun 14, 1961 – Jul 8, 1961 | -0.7% | -0.8% |
| Feb 18, 1961 – Feb 25, 1961 | Feb 12, 1961 – Mar 6, 1961 | +0.3% | +0.9% |
| Nov 4, 1960 – Nov 11, 1960 | Oct 27, 1960 – Nov 16, 1960 | +0.4% | +2.6% |
| Jul 12, 1960 – Jul 21, 1960 | Jul 3, 1960 – Jul 27, 1960 | -1.0% | -3.1% |
| Mar 7, 1960 – Mar 14, 1960 | Mar 1, 1960 – Mar 24, 1960 | -1.0% | -0.5% |
| Nov 21, 1959 – Nov 27, 1959 | Nov 13, 1959 – Dec 3, 1959 | +0.2% | +1.3% |
| Aug 2, 1959 – Aug 9, 1959 | Jul 22, 1959 – Aug 15, 1959 | -3.4% | -3.1% |
| Mar 25, 1959 – Apr 2, 1959 | Mar 19, 1959 – Apr 11, 1959 | -0.8% | +0.1% |
| Dec 6, 1958 – Dec 13, 1958 | Nov 30, 1958 – Dec 19, 1958 | 0.0% | +1.3% |
| Aug 20, 1958 – Aug 27, 1958 | Aug 9, 1958 – Sep 2, 1958 | +0.7% | +1.3% |
| Apr 12, 1958 – Apr 21, 1958 | Apr 6, 1958 – Apr 30, 1958 | +0.6% | +3.0% |
| Dec 22, 1957 – Dec 28, 1957 | Dec 16, 1957 – Jan 5, 1958 | +0.1% | +0.8% |
| Sep 6, 1957 – Sep 13, 1957 | Aug 27, 1957 – Sep 19, 1957 | -1.8% | -0.0% |
| May 1, 1957 – May 10, 1957 | Apr 25, 1957 – May 18, 1957 | +0.2% | +1.9% |
| Jan 7, 1957 – Jan 13, 1957 | Jan 1, 1957 – Jan 21, 1957 | -1.2% | -1.7% |
| Sep 23, 1956 – Sep 30, 1956 | Sep 13, 1956 – Oct 5, 1956 | -3.7% | -4.0% |
| May 20, 1956 – May 30, 1956 | May 14, 1956 – Jun 7, 1956 | -4.1% | -2.8% |
| Jan 24, 1956 – Jan 30, 1956 | Jan 18, 1956 – Feb 8, 1956 | -0.7% | +0.9% |
| Oct 10, 1955 – Oct 17, 1955 | Oct 1, 1955 – Oct 22, 1955 | -0.8% | -2.4% |
| Jun 11, 1955 – Jun 20, 1955 | Jun 3, 1955 – Jun 27, 1955 | +0.9% | +2.9% |
| Feb 9, 1955 – Feb 15, 1955 | Feb 3, 1955 – Feb 25, 1955 | +0.1% | +1.2% |
| Oct 26, 1954 – Nov 2, 1954 | Oct 18, 1954 – Nov 7, 1954 | -0.8% | -0.5% |
| Jul 1, 1954 – Jul 10, 1954 | Jun 23, 1954 – Jul 17, 1954 | +1.3% | +3.2% |
| Feb 25, 1954 – Mar 4, 1954 | Feb 20, 1954 – Mar 14, 1954 | +0.9% | +2.3% |
| Nov 11, 1953 – Nov 17, 1953 | Nov 3, 1953 – Nov 23, 1953 | -0.5% | -1.7% |
| Jul 21, 1953 – Jul 29, 1953 | Jul 11, 1953 – Aug 4, 1953 | -0.4% | +0.2% |
| Mar 14, 1953 – Mar 22, 1953 | Mar 9, 1953 – Apr 1, 1953 | 0.0% | -0.4% |
| Nov 27, 1952 – Dec 3, 1952 | Nov 20, 1952 – Dec 9, 1952 | +0.3% | +1.4% |
| Aug 9, 1952 – Aug 16, 1952 | Jul 29, 1952 – Aug 22, 1952 | -1.4% | -1.3% |
| Apr 1, 1952 – Apr 9, 1952 | Mar 26, 1952 – Apr 18, 1952 | -1.6% | -1.8% |
| Dec 13, 1951 – Dec 20, 1951 | Dec 7, 1951 – Dec 27, 1951 | -0.1% | +0.9% |
| Aug 28, 1951 – Sep 4, 1951 | Aug 17, 1951 – Sep 9, 1951 | +0.8% | +1.9% |
| Apr 20, 1951 – Apr 29, 1951 | Apr 14, 1951 – May 8, 1951 | -0.4% | +1.8% |
| Dec 29, 1950 – Jan 4, 1951 | Dec 23, 1950 – Jan 12, 1951 | +1.3% | +2.4% |
| Sep 14, 1950 – Sep 21, 1950 | Sep 3, 1950 – Sep 26, 1950 | +0.2% | +1.5% |
| May 9, 1950 – May 19, 1950 | May 3, 1950 – May 27, 1950 | -0.5% | +2.2% |
| Jan 14, 1950 – Jan 20, 1950 | Jan 8, 1950 – Jan 29, 1950 | +0.3% | +0.8% |
Why the Claim Feels So True
1. Two of the scariest weeks in market history are on the reel
October 3, 2008: the combust window opens, and the S&P 500 loses 18.2% in five days. February 22, 2020: the window opens, and COVID hits the tape within days. Coincidences this vivid do the believing for you — and the other 240 windows never make the reel.
2. “Double condition” sounds rare — it happens three times a year
Stacking qualifiers makes an event sound exclusive, but combust-and-retrograde is the guaranteed middle third of every retrograde. Any ordinary ~8-day stretch that recurs three times a year will contain its share of bad weeks — about one in five, to be exact.
3. The conditions aren't independent
The intuition multiplies two dangers together. But combustion during retrograde isn't a second coin coming up tails — it is the same geometry as the retrograde midpoint we already tested, widened by a few days. Correlated conditions don't stack evidence; they repackage it.
4. Nobody runs the inside-vs-outside comparison
“Markets are choppy when Mercury is combust and retrograde” is unfalsifiable by eyeball, because markets are choppy, period: 31% of all days swing 1.5% high-to-low. Put the 1,401 inside days next to the 17,800 outside days and the chop is identical to a tenth of a percent.
Frequently Asked Questions
What does “Mercury combust and retrograde” mean?
Combust = within about 8.5° of the Sun; retrograde = apparent backwards motion. They overlap in the middle of every retrograde: Mercury enters the orb about a week after stationing, passes the inferior conjunction (cazimi), and exits before stationing direct — a 7–12 day window, three times a year.
Does the market drop after Mercury becomes combust and retrograde?
No: 2% closing drops followed 15.8% of the 241 evaluable entries within five days, against an 18.2% any-day base rate. Wicks: 24.5% vs. 26.6%. Seven of eight tested combinations sit below their base rates.
Is the market more volatile inside the window?
Not measurably: average daily range 1.19% inside vs. 1.17% outside, 1.5%+ range days 31.3% vs. 31.2%, up days 53.2% vs. 53.1%. Across 1,401 inside days, no test separates them from the rest of the tape.
Didn't 2008 and 2020 crash inside these windows?
Yes — the October 2008 window preceded an 18.2% five-day collapse and the February 2020 window opened days before the COVID crash. They are 2 of 242. With ~8-day windows three times a year, the windows cover about 7% of all trading days — roughly 7% of everything, crashes included, lands in one.
How were the windows computed?
Daily geocentric Mercury and Sun positions from a Swiss Ephemeris, 1950–2026; retrograde motion from the wrap-aware day-over-day longitude delta; combustion from the full angular separation (longitude and latitude) against the traditional 8.5° orb.
This is the third Mercury-retrograde claim we've tested: the midpoint-reversal claim and the 2%-drop-after-the-station claim failed the same way: real astronomy, honest anecdotes, and a base rate nobody ran.
Patterns That Survive the Base-Rate Test
Seasonal Edge backtests every calendar and cycle pattern against decades of data — win rates, profit factors, and regime filters included — so you can see which recurring dates actually held up historically and which are folklore.
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