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This image, from ESO’s VISTA telescope, shows a newly-discovered brown dwarf nicknamed VVV BD001, which is located at the very centre of this image. It is the first new brown dwarf spotted in our cosmic neighbourhood as part of the VVV Survey. VVV BD001 is located about 55 light-years away from us, towards the very crowded centre of our galaxy. Brown dwarfs are stars that never quite managed to grow up into a star like our Sun. They are often referred to as “failed stars”; they are larger in size than planets like Jupiter, but smaller than stars. This dwarf is peculiar in two ways; firstly, it is the first one found towards the centre of our Milky Way, one of the most crowded regions of the sky. Secondly, it belongs to an unusual class of stars known as “unusually blue brown dwarfs” — it is still unclear why these stars are bluer than expected. Brown dwarfs are born in the same way as stars, but do not have enough mass to trigger the burning of hydrogen to become normal stars. Because ...

This view of Comet C/2012 S1 (ISON) was taken with the TRAPPIST–South national telescope at ESO's La Silla Observatory on the morning of Friday 15 November 2013. Comet ISON was first spotted in our skies in September 2012, and will make its closest approach to the Sun in late November 2013. TRAPPIST–South has been monitoring comet ISON since mid-October, using broad-band filters like those used in this image. It has also been using special narrow-band filters which isolate the emission of various gases, allowing astronomers to count how many molecules of each type are released by the comet. Comet ISON was fairly quiet until 1 November 2013, when a first outburst doubled the amount of gas emitted by the comet. On 13 November, just before this image was taken, a second giant outburst shook the comet, increasing its activity by a factor of ten. It is now bright enough to be seen with a good pair of binoculars from a dark site, in the morning skies towards the East. Over the past coupl...

When seen up close, the F ring of Saturn resolves into multiple dusty strands. This Cassini view shows three bright strands and a very faint fourth strand off to the right. The central strand is the core of the F ring. The other strands are not independent at all, but are actually sections of long spirals of material that wrap around Saturn. The material in the spirals was likely knocked out from the F ring's core during interactions with a small moon. This view looks toward the unilluminated side of the rings from about 38 degrees above the ring plane. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on December 18, 2016. The view was acquired at a distance of approximately 122,000 miles (197,000 kilometers) from Saturn and at a Sun-Ring-spacecraft, or phase, angle of 47 degrees. Image scale is 0.7 miles (1.2 kilometers) per pixel. Image Credit: NASA/JPL-Caltech/Space Science Institute Explanation from: https://photojournal.jpl.nasa.gov/catalog/...

NASA's Solar Dynamics Observatory captured this image of a solar flare peaking at 4:02 a.m. EDT on April 2, 2017, as seen in the bright flash near the Sun’s upper right edge. The image shows a subset of extreme ultraviolet light that highlights the extremely hot material in flares and which is typically colorized in blue. NASA's Solar Dynamics Observatory captured this image of a solar flare peaking at 4:33 p.m. EDT on April 2, 2017, as seen in the bright flash near the Sun’s upper right edge. The image shows a subset of extreme ultraviolet light that highlights the extremely hot material in flares and which is typically colorized in blue. NASA's Solar Dynamics Observatory captured this image of a solar flare peaking at 10:29 a.m. EDT on April 3, 2017, as seen in the bright flash near the Sun’s upper right edge. The image shows a subset of extreme ultraviolet light that highlights the extremely hot material in flares and which is typically colorized in teal. The Sun emitted...

A mysterious X-ray source became 1,000 times brighter over a few hours before fading dramatically in about a day. This source was discovered in Chandra Deep Field-South data, giving the deepest X-ray image ever made. Hubble and Spitzer data indicate this source is likely located in a small galaxy about 10.7 billion light years from Earth. Evidence points to this being some sort of destructive event but perhaps unlike any ever seen before. Scientists have discovered a mysterious flash of X-rays using NASA's Chandra X-ray Observatory, in the deepest X-ray image ever obtained. The X-ray source is located in a region of the sky known as the Chandra Deep Field-South (CDF-S), which is shown in the main panel of this graphic. Over the 17 years Chandra has been operating, the telescope has observed this field many times, resulting in a total exposure time of 7 million seconds, equal to two and a half months. In this CDF-S image, the colors represent different bands of X-ray energy, where r...

Osorno, Los Lagos, Chile Image Credit: Ivan Alvarado

This image depicts the dusty disc encircling the young, isolated star HD 169142. The Atacama Large Millimeter/submillimeter Array (ALMA) imaged this disc in high resolution by picking up faint signals from its constituent millimetre-sized dust grains. The vivid rings are thick bands of dust, separated by deep gaps. Optimised to study the cold gas and dust of systems like HD 169142, ALMA’s sharp eyes have revealed the structure of many infant solar systems with similar cavities and gaps. A variety of theories have been proposed to explain them — such as turbulence caused by magnetorotational instability, or the fusing of dust grains — but the most plausible explanation is that these pronounced gaps were carved out by giant protoplanets. When solar systems form gas and dust coalesce into planets. These planets then effectively spring clean their orbits, clearing them of gas and dust and herding the remaining material into well-defined bands. The deep gaps seen in this image are consisten...

In this image taken March 24, 2017, comet 41P/Tuttle-Giacobini-Kresák is shown moving through a field of faint galaxies in the bowl of the Big Dipper. On April 1, the comet will pass by Earth at a distance of about 13 million miles (0.14 astronomical units), or 55 times the distance from Earth to the moon; that is a much closer approach than usual for this Jupiter-family comet. On April 1, 2017, comet 41P will pass closer than it normally does to Earth, giving observers with binoculars or a telescope a special viewing opportunity. Comet hunters in the Northern Hemisphere should look for it near the constellations Draco and Ursa Major, which the Big Dipper is part of. Whether a comet will put on a good show for observers is notoriously difficult to predict, but 41P has a history of outbursts, and put on quite a display in 1973. If the comet experiences similar outbursts this time, there’s a chance it could become bright enough to see with the naked eye. The comet is expected to reach pe...

ISS, Orbit of the Earth September 2016 Image Credit: NASA/ESA

A KBO among the Stars: In preparation for the New Horizons flyby of 2014 MU69 on Jan. 1, 2019, the spacecraft’s Long Range Reconnaissance Imager (LORRI) took a series of 10-second exposures of the background star field near the location of its target Kuiper Belt object (KBO). This composite image is made from 45 of these 10-second exposures taken on Jan. 28, 2017. The yellow diamond marks the predicted location of MU69 on approach, but the KBO itself was too far from the spacecraft (544 million miles, or 877 million kilometers) even for LORRI’s telescopic “eye” to detect. New Horizons expects to start seeing MU69 with LORRI in September of 2018 – and the team will use these newly acquired images of the background field to help prepare for that search on approach. How time and our spacecraft fly – especially when you’re making history at 32,000 miles (51,500 kilometers) per hour. Continuing on its path through the outer regions of the solar system, NASA’s New Horizons spacecraft has now...

Ever since Voyager 2 beamed home spectacular images of the planets in the 1980s, planet-lovers have been hooked on extra-terrestrial aurorae. Aurorae are caused by streams of charged particles like electrons, that come from various origins such as solar winds, the planetary ionosphere, and moon volcanism. They become caught in powerful magnetic fields and are channelled into the upper atmosphere, where their interactions with gas particles, such as oxygen or nitrogen, set off spectacular bursts of light. The alien aurorae on Jupiter and Saturn are well-studied, but not much is known about the aurorae 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 aurorae on Uranus. In 2012 and 2014 a team led by an astronomer from Paris Observatory took a second look at the aurorae using the ultraviolet capabilities of the Space Telescope Imaging Spectrograph (STIS) installed on Hubble. They tracked the interpl...