About this episode

This episode discusses how a passing star may have redirected comets and the new understanding of the Milky Way's structure.

Sponsor Link : This episode of SpaceTime is brought to you by Incon i. Take back your privacy and data online with Incogni. Check out our special offer: www.incogni.com/stuartgary SpaceTime Series 29 Episode 81 How a passing star redirected comets to the inner solar system A fascinating new study reveals how a passing star, HD 7977, may have altered the trajectory of comets from the Oort Cloud, sending them cascading into the inner solar system. This event, which occurred approximately 2.47 billion years ago, could still be influencing comet activity today. Researchers used data from the European Space Agency's Gaia mission to refine the distances involved and suggest that the gravitational perturbations from HD 7977 temporarily dominated the generation of new comets. Changing our map of the Milky Way Galaxy Astronomers have redrawn the map of our Milky Way galaxy, moving its outer arms up to 10% further away than previously estimated. This revised picture is based on observations of gamma-ray bursts and the subsequent echoes of X-rays that helped to measure distances within the galaxy. New techniques have allowed for a clearer understanding of the Milky Way's structure…

People in this episode

Host: Stuart Gary

Topics covered

• comet trajectories
• Milky Way structure
• Mars geology
• gravitational perturbations
• Oort Cloud
• gamma-ray bursts
• X-ray echoes

Keywords

• comets
• Oort Cloud
• HD 7977
• Milky Way
• Mars
• gravitational perturbations
• gamma-ray bursts
• InSight mission
• Gaia mission
• X-ray echoes

Sponsors

Incon i

Mentioned in this episode

Organizations: European Space Agency, NASA

Places: Mars, Milky Way

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