Comet 41P/Tuttle-Giacobini-Kresák slows down, stops and rotates in the opposite direction reveals recent Hubble analysis

A new astronomical study confirmed that comet 41P/Tuttle-Giacobini-Kresák, from the Júpiter family, suffered an extreme change in its rotation during its approach to Sol in 2017. Observações carried out with Telescópio Espacial Hubble captured the nucleus slowing down sharply between March and May of that year. The rotational period went from about 20 hours to more than 46 hours, until it almost stopped completely.

After perihelion, the point of closest proximity to Sol, the comet reappeared with rotation in the opposite direction and a period reduced to approximately 14 hours. Esse behavior represents the first confirmed record of rotational inversion on a comet. The data was analyzed by researchers led by experts in cometary dynamics.

The jets of gas released by the sublimation of the ice in the core acted as natural thrusters and generated enough torque to alter the movement. Esse process highlights the fragility of small cometary bodies in Sistema Solar.

Detailed Observations of Hubble

Telescópio Espacial Hubble recorded sequential images that made it possible to measure variations in the brightness of comet 41P. Essas variations reveal changes in the rotation period over the weeks of observation. The scientists identified that the deceleration occurred progressively until the nucleus reached a state of almost rotational immobility.

The proximity to Sol intensified the comet’s activity and increased the release of volatile material. Essa release created asymmetric forces that directly influenced the axis of rotation.

Sublimation jet mechanism

Comets like 41P have cores composed mainly of water ice, carbon dioxide and other frozen compounds. Quando approach Sol, the heat causes the direct sublimation of these ices into gas. The resulting jets escape in specific directions and generate thrust similar to small rockets.

In the case of 41P, the irregular distribution of these jets produced enough torque to decelerate and subsequently reverse the rotation. Esse effect known as non-equilibrium outgassing is common in active comets, but rarely reaches such extreme magnitudes.

The observed inversion demonstrates how non-gravitational forces can dominate the dynamics of small bodies. Previous Pesquisas had already predicted this type of instability, but 41P provided the first direct evidence.

Variations in rotational period

• Initial period recorded: approximately 20 hours before the greatest activity;
• Gradual increase: reached more than 46 hours in May 2017;
• Post-perihelion state: reduction to around 14 hours with reversed direction;
• Total variation: more than double the original period in a few weeks.

These changes highlight the direct influence of surface activity on rotational dynamics.

Implications for cometary evolution

Extreme rotational changes like those of 41P accelerate the fragmentation process in small comets. The increased centrifugal force can overcome the weak gravity of the core and cause ruptures. Muitos comets from the Júpiter family exhibit signs of similar instability over multiple orbits.

The study indicates that this mechanism contributes significantly to the loss of cometary mass in the inner Sistema Solar. Corpos with a diameter estimated at a few kilometers are particularly vulnerable to these events.

Risk of future disintegration

Comet 41P may face rotational breakup in the coming decades due to accumulated instability. Accelerated rotation in the opposite direction increases internal stresses in the core. Observações indicate that comets with short periods often terminate their activity by complete fragmentation.

Next passages through perihelion will intensify the jets and could trigger structural collapse. Esse process explains the relative scarcity of small comets observed in stable orbits.

Comparisons with other comets

Several comets showed rotational changes, but none with the magnitude recorded in 41P. Comet 103P/Hartley exhibited rotational excitation in a previous passage, but without complete inversion. Outros bodies like 67P/Churyumov-Gerasimenko showed moderate variations during the Rosetta mission.

• Comet 103P/Hartley: period increase of around 50%;
• Comet 67P: local changes due to asymmetric activity;
• Comet 41P: period doubling followed by reversal.

These differences reinforce the uniqueness of the case studied.

Upcoming Observation Opportunities

Comet 41P will return to perihelion in 2028 and offer a new chance for detailed monitoring. Observatórios terrestrial and space scientists will be able to monitor possible additional changes in rotation. The Vera C. Rubin Observatory, with recently started operations, will allow systematic tracking of variations in multiple comets.

These facilities will capture high-resolution data on surface activity and rotational dynamics. Ongoing monitoring will help predict behaviors in other similar bodies.

Importance for understanding Sistema Solar

Phenomena like the one observed in 41P reveal physical processes that act on small scales in Sistema Solar. The interplay between sublimation and non-gravitational torque shapes the evolution of comets over time. Estudos based on data from Hubble continues to provide valuable information years after the original observations.

The detailed analysis reinforces theoretical models about rotational instability in icy bodies. Esses knowledge contributes to future missions aimed at comets and asteroids.

41P’s behavior demonstrates the dynamic complexity of objects that preserve primordial material from Sistema Solar. The preservation of these records depends on rotational stability throughout the orbits.