On May 12, 2016, the Hubble Space Telescope captured a series of images of Mars and in them the planet’s moon Phobos can be seen appearing from behind the western limb. This was just 10 days before opposition which, in 2016, was the closest Mars had been to Earth since 2005, lending particularly good opportunity for picking out its largest—yet still quite small—moon.
Ok, technically it’s not a new moon as it’s probably several billion years old but we didn’t know about it before, so it’s new to us! A team of researchers has just announced the discovery of a 150- to 250-mile-wide moon orbiting a dwarf planet in the Kuiper Belt named 2007 OR10. This distant, icy world is only 950 miles wide itself but it’s still the third largest dwarf planet, ranking behind Pluto and Eris in size.
The existence of the moon was first hinted at in observations by NASA’s Kepler telescope, which showed 2007 OR10 to be rotating suspiciously slowly for a KBO—45 hours as compared to a more typical under 24. After reviewing earlier Hubble observations of the object a moon was positively identified.
This discovery not only adds a new member to the Solar System’s family tree but also helps better understand the formation of KBOs.
“The discovery of satellites around all of the known large dwarf planets—except for Sedna—means that at the time these bodies formed billions of years ago, collisions must have been more frequent, and that’s a constraint on the formation models,” said Csaba Kiss of the Konkoly Observatory in Budapest, Hungary, lead author of the research. “If there were frequent collisions, then it was quite easy to form these satellites.”
Read the full article from NASA’s Goddard Space Flight Center here: Hubble Spots Moon Around Third Largest Dwarf Planet
Those white areas aren’t clouds; they’re aurorae—”northern lights”—around the poles of Uranus, captured by the Hubble Space Telescope in 2012 and 2014. (The image of Uranus itself was acquired by the Voyager 2 spacecraft in January 1986.)
“The auroras on Jupiter and Saturn are well-studied, but not much is known about the auroras of the giant ice planet Uranus. In 2011, the NASA/ESA Hubble Space Telescope became the first Earth-based telescope to snap an image of the auroras on Uranus. In 2012 and 2014 a team led by an astronomer from Paris Observatory took a second look at the auroras using the ultraviolet capabilities of the Space Telescope Imaging Spectrograph (STIS) installed on Hubble.”
Aurorae on Uranus are driven by the same process that creates them around Earth’s polar regions: charged particles from the Sun get caught in the planet’s magnetic field and are focused toward the poles, where they make ions in the upper atmosphere release energy—in these observations in ultraviolet wavelengths. Also, since Uranus orbits the Sun “tilted sideways” its polar regions are near the plane of its orbit.
Read the rest of this article from NASA here: Hubble Spots Auroras on Uranus
On April 3, 2017, as Jupiter made its nearest approach to Earth in a year, NASA’s Hubble Space Telescope viewed the solar system’s largest planet in all of its up-close glory. At a distance of 415 million miles (668 million km) from Earth, Jupiter offered spectacular views of its colorful, roiling atmosphere, the legendary Great Red Spot, and its smaller companion at farther southern latitudes dubbed “Red Spot Jr.” Taken with Hubble’s Wide Field Camera 3, the image resolves details in Jupiter’s atmosphere as small as about 80 miles (129 km) across.
Read the full article on NASA’s Hubble site here, and check out a version I made with enhanced contrast and sharpness to bring out some details in Jupiter’s clouds below:
Astronomers still have yet to directly capture an image of a black hole—they’re working on it—but they know where some of the largest ones are: inside the hearts of galaxies, where they power brilliant and powerful quasars whose light can be seen across the Universe. Some of these supermassive black holes (SMBs) can contain the mass of millions if not billions of Sun-sized stars and, when two galaxies happen to collide (which they often do) their respective resident SMBs can end up locked in an orbital embrace. As their spinning dance grows tighter and tighter they send out gravitational waves, rippling the very fabric of space and time itself (the LIGO experiment announced the first detection of these waves in 2016.) But if the gravitational waves are uneven, say because the two merging SMBs are of vastly different masses and/or individually spinning in different orientations (a possible but not common scenario) then the super-duper-supermassive black hole that results from the merger can end up getting one serious cosmic-scale kick after the event occurs and the waves shut off—perhaps a strong enough kick to send it hurtling out of the galaxy altogether.
That’s what astronomers think we’re witnessing here in this image from the Hubble Space Telescope.