How to Read a SPY Options Trading Signal
Image credit: NASA, ESA, STScI; Image Processing: Joseph DePasquale

How to Read a SPY Options Trading Signal

•By The astronomer Team

A SPY options trading signal highlights unusual activity detected in the options market for the SPDR S&P 500 ETF Trust. Astronomer records each signal as it occurs so traders can review the contract, its timing, and what SPY did afterward.

Here are the primary fields you will see and what they mean.

Call or put

A call signal identifies activity in SPY call options, while a put signal identifies activity in SPY put options.

Call activity is often interpreted as bullish and put activity as bearish, but the label does not reveal every participant's position or strategy. Calls and puts can both be bought or sold.

For that reason, an Astronomer signal should be treated as an observation of options-market activity—not an automatic instruction to enter a trade.

Strike price

The strike is the price at which the option contract can be exercised.

Comparing the strike with SPY's price when the signal was detected provides useful context. It helps show whether the contract was in the money, near the money, or out of the money at that moment.

The strike price alone does not indicate how strong or reliable a signal is.

Expiration date

The expiration date tells you when the option contract expires and how much time remains for SPY to move.

Short-dated contracts have less time for an anticipated move to occur. Always confirm the expiration rather than evaluating the call or put direction by itself.

The SEC's [introduction to options](https://www.investor.gov/introduction-investing/general-resources/news-alerts/alerts-bulletins/ investor-bulletins-63) provides additional background on calls, puts, strike prices, and expirations.

Detection time and SPY price

Astronomer records when a signal was detected along with SPY's underlying price context at that time. This creates a timestamped reference point for reviewing what happened next without relying on hindsight.

Time of day can also matter. Activity near the opening bell may occur under different market conditions than activity later in the session.

Observed movement

Historical signal pages show how the underlying SPY price moved following detection.

These figures should not be interpreted as actual option profit and loss. Option returns also depend on the premium paid, implied volatility, time decay, bid-ask spreads, execution, and fees.

Putting the signal together

A SPY options trading signal is best read as a combination of:

  1. Direction — call or put activity
  2. Strike — the contract's exercise price
  3. Expiration — how much time remains
  4. Detection time — when the activity was identified
  5. Underlying-price context — where SPY was trading and how it moved afterward

No single field should be evaluated in isolation. Review the complete signal, consider current market conditions, and conduct your own research before making a trading decision.

Browse the latest SPY options trading signals, explore the SPY call signal archive and SPY put signal archive, or learn more about how Astronomer generates its signals.

For educational purposes only. Astronomer signals are observations of market activity, not financial advice or a recommendation to buy or sell any security. Options trading involves substantial risk, including the possible loss of principal.