Astronomers have measured the two most enormous supermassive black holes found so far, vast realms of titanic gravity large enough to swallow 10 of our solar systems. The black holes are much bigger than predicted, suggesting extra-large galaxies and their black holes grow and evolve differently than smaller ones.
Like city lights blinding the night sky, the sun blocks out a lot of the signals from our galactic neighborhood. Our star and its magnetic fields shield the planets from cosmic rays and the interstellar wind — by and large a good thing, but it’s somewhat frustrating if you want to study the galaxy in greater detail. We cannot see, for instance, the hydrogen signals that serve as the birth pangs of stars in our neighborhood. Until now — the Voyager spacecraft have seen it for the first time.
Pluto may not be a fully fledged planet, but at least it’s not the dwarfiest of dwarf planets. Its sibling, Eris, is not as large as astronomers thought, according to a new study. A rare stellar blockage event last year helped astronomers obtain some new measurements of the distant icy world, and they say it is quite dense and it may develop a feeble atmosphere as it moves closer to the sun.
A “violent encounter with Jupiter” may have hurled a fifth gas giant out of our solar system billions of years ago. A simulation done by the Southwest Research Institute in Boulder, Colorado suggests that our solar system may have included another gaseous giant, placed between Saturn and Uranus. The computer models may prove how the planets of our solar system settled in their current position, a long-standing source of mystery to astronomers.
According to some tricky calculations from Guillaume Robuchon and Francis Nimmo at the University of California, Santa Cruz, Pluto may actually have a liquid ocean underneath its frigid, -230 °C exterior. It's mostly speculation, but the reasoning is pretty sound: if Pluto's rocky core has a certain level of potassium, "its decay could produce enough heat to melt some of the overlaying ice," says New Scientist. The assumption is that Pluto does, since the Earth has 10 times that amount despite being closer to the sun and therefore likely having much less potassium in its core than Pluto. We just hope having an ocean makes Pluto feel better about not being a planet anymore. [New Scientist]
Proponents of panspermia theory say life on Earth came from elsewhere, hitching a ride on rocks sheared from other worlds or from migratory asteroids. But what if life did originate here and then it left, hitching a ride on Earth-departed rocks? Earth could seed other worlds, instead of the other way around. A new analysis says the rocks could conceivably make it as far as Jupiter.
Exploring the final frontiers requires a delicate balancing act between competing engineering needs. To probe the mysteries of inhospitable places, from ocean trenches to the blistering atmosphere of the sun, scientific instruments must be tough yet ultra-sensitive — they have to survive their environments but remain exposed just enough to do their jobs. Balancing protection and intentional vulnerability can be a major challenge. A NASA spacecraft launching this morning marks a new leap forward in meeting this balance.
A primordial second moon may have smacked into our existing moon billions of years ago, its remains pancaking across its larger sibling and disrupting the bigger moon’s still-cooling surface. This new theory could explain why the moon’s far side looks so different from the one that perennially faces us.
Peering at Pluto in preparations for a satellite visit in 2015, the Hubble Space Telescope has spotted a fourth moon orbiting the dwarf planet. The wee moon doesn't even have a name yet — it's called P4 for now — and its estimated diameter is between 8 and 21 miles.
That's right, Hubble spotted something the size of a city from a distance of more than 3 billion miles away.
It's been a long year for Neptune. A full 165 Earth years ago, German astronomer Johann Galle first spied the icy blue giant giving wide berth to the sun some 2.8 billion miles from the solar system's center. Today, it's right back where we found it again, marking one full Neptune year since the planet's discovery.
Neptune, of course, has a somewhat tumultuous and storied history. It was the most distant planet in our solar system before Pluto was discovered in 1930, pushing Neptune to 8th and second-most-distant. When Pluto was downgraded to a dwarf planet it was again elevated to superlative status.