The New Horizons i probe has just sent back its first real shots of Ultima Thule, a 21-mile-long rock or planetesimal deep in the reaches of the solar system — and now the most distant object ever visited up close by mankind. The principal investigator of the mission, Alan Stern, called the accomplishment “a technical success beyond anything ever attempted before in spaceflight.â€
Ultima Thule is, as early occultation studies suggested with remarkable success, what’s called a contact binary object, composed of two individual objects fused together likely through impact billions of years ago — and it’s the first ever photographed up close. This is like candy for planet scientists: learning about the creation and characteristics of this interesting type of object is a chance decades — nay, centuries — in expectation.
More at:
https://techcrunch.com/2019/01/02/behold-ultima-thule-the-most-distant-object-ever-explored-by-a-spacecraft/