May 16, 2019

Leftover debris could tell scientists about the evolution of the solar system

Ultima Thule viewed on Jan. 1, 2019. Image: NASA/JHU-APL/SwRI/NOAO

Newly analyzed results from NASA’s New Horizons flyby of Ultima Thule reveal clues about the evolution of our solar system, according to a new study published in the journal Science.

Why it matters: New Horizons found that Ultima Thule appears to be leftover debris from the early days of the solar system and has remained largely untouched by the heat of the sun since it formed 4.5 billion years ago. This means that any data gathered could help researchers piece together the ancient history of our solar system.

What they found: Ultima Thule — which is located 1 billion miles from Pluto in a part of space called the Kuiper Belt — likely formed when two objects gently smushed together during the early days of the solar system.

  • This type of formation runs counter to one of the leading theories that these deep space objects formed in chaos, violently crashing into one another at the speed of a bullet.
  • But if the two lobes of 2014 MU96 — unofficially called Ultima and Thule — smacked into each other at those speeds, “they would blow each other to smithereens,” study co-author Alan Stern told Axios.
  • Instead, New Horizons found the two lobes touching one another, forming what’s known as a “contact binary.”

The backdrop: New Horizons made its flyby of Ultima Thule on Jan. 1. The spacecraft launched from Earth in 2006 on a mission to Pluto. New Horizons made its planned encounter with Pluto in 2015.

What’s next: The new study was reportedly written with only about 10% of data collected during the flyby, so future studies should reveal even more about the nature of MU69 and other objects.

  • New Horizons is still in good health. Scientists working on the mission are now looking to the future, thinking about another possible extended mission.

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  3. Trump administration: Mike Pence's press secretary returns to work after beating coronavirus.
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Updated 31 mins ago - Politics & Policy

Pentagon watchdog sidelined by Trump resigns

Fine testiying before the Senate Judiciary Committee in 2017. Photo: Drew Angerer/Getty Images

Glenn Fine, the Pentagon's principal deputy inspector general, submitted his resignation on Tuesday.

Why it matters: President Trump removed Fine as the Pentagon's acting inspector general in April 7 after a group of independent federal watchdogs selected him to lead the Pandemic Response Accountability Committee, which was set up to oversee the rollout of the $2 trillion coronavirus relief bill.

New York reports lowest number of daily coronavirus deaths since March

The number of daily new coronavirus cases and deaths reported in New York was the lowest since the state started its lockdown in March, Gov. Andrew Cuomo said Tuesday, calling Memorial Day a "pivot point" for New York.

By the numbers: 73 New Yorkers died from coronavirus in the past 24 hours, and 200 people tested positive. Hospitalizations and intubations also decreased.