Astronomy | Penn Today

Evidence of broadside collision with a dwarf galaxy discovered in the Milky Way

“Shell structures,” the result of a collision with another galaxy nearly 3 billion years, have been confirmed in the Milky Way galaxy for the first time.

an artists impression of venus, shown half in shadow with a cream and tan colored atmosphere

Did scientists detect chemical signals from Venusian microorganisms?

Four takeaways from astronomer Cullen Blake on what this potentially groundbreaking study shows and what comes next for scientists who are keen to understand these faraway chemical signals.

a simulated view of the Milky Way galaxy

New stellar stream, born outside the Milky Way, discovered with machine learning

Finding this new stellar stream, named after Nyx, the Greek goddess of night, was made possible using machine learning tools and simulations of data collected by the Gaia space observatory.

the Atacama Cosmology Telescope in the foreground and the desert and mountains of chile in the background

New view of nature’s oldest light adds fresh twist to debate over universe’s age

Observations by the Atacama Cosmology Telescope suggest that the universe is 13.77 billion years old, and reveals how fast the cosmos is expanding.

researching working in simons observatory

Additional challenges in bringing research online

As research on campus slowly restarts, those whose work requires field surveys, large-scale collaborations, or travel face additional challenges in bringing their research back online.

a telescope dome bathed in red light with the milky way galaxy behind it

New minor planets beyond Neptune

This updated catalog of trans-Neptunian objects and the methods used to find them could aid in future searches for undiscovered planets in the far reaches of the solar system.

New astronomical instrument on the hunt for exoplanets

A state-of-the-art instrument called NEID, from the Tohono O’odham word meaning “to see,” collected its “first light” and is poised to look for new planets outside the solar system.

a map showing lines between a map of galaxies, shown as colored points across a dark sky

A new way to measure cosmic black holes

Researchers find a link between the masses of supermassive black holes and the distances between the galaxies which surround them, allowing astronomers to more easily study many astronomical phenomena.

a cluster of galaxies shown against a dark blue background, a faint darker ring can be seen around the center of the image

By the Numbers

By the Numbers: Dark matter

Key facts and figures about the unseen matter that remains one of cosmology’s greatest unsolved mysteries.

Our solar system’s mysterious ‘Planet 9’ may actually be a tiny, ancient black hole

Bhuvnesh Jain of the School of Arts and Sciences commented on a new theory that Planet 9 may actually be a tiny, primordial black hole: “From a theoretical standpoint, it’s exciting even if its plausibility right now is early to judge.”

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