ESO Archives

December 21, 2019December 21, 2019 by Matt Williams

Black Holes Were Already Feasting Just 1.5 Billion Years After the Big Bang

This illustration depicts a gas halo surrounding a quasar in the early Universe. The quasar, in orange, has two powerful jets and a supermassive black hole at its centre, which is surrounded by a dusty disc. The gas halo of glowing hydrogen gas is represented in blue. A team of astronomers surveyed 31 distant quasars, seeing them as they were more than 12.5 billion years ago, at a time when the Universe was still an infant, only about 870 million years old. They found that 12 quasars were surrounded by enormous gas reservoirs: halos of cool, dense hydrogen gas extending 100 000 light years from the central black holes and with billions of times the mass of the Sun. These gas stashes provide the perfect food source to sustain the growth of supermassive black holes in the early Universe.

Thanks to the vastly improved capabilities of today’s telescopes, astronomers have been probing deeper into the cosmos and further back in time. In so doing, they have been able to address some long-standing mysteries about how the Universe evolved since the Big Bang. One of these mysteries is how supermassive black holes (SMBHs), which play a crucial role in the evolution of galaxies, formed during the early Universe.

Using the ESO’s Very Large Telescope (VLT) in Chile, an international team of astronomers observed galaxies as they appeared about 1.5 billion years after the Big Bang (ca. 12.5 billion years ago). Surprisingly, they observed large reservoirs of cool hydrogen gas that could have provided a sufficient “food source” for SMBHs. These results could explain how SMBHs grew so fast during the period known as the Cosmic Dawn.

July 18, 2019July 18, 2019 by Evan Gough

Asteroid 2006 QV89 Now Has a 0% Chance of Hitting Earth in September

An artistic composite image of asteroid Lutetia, which flew by Earth in March, 2014. Image Credit; ESA

Why report on an asteroid that has no chance of hitting Earth? Because this asteroid, known as 2006 QV89, has a history. A history of being kind of hard to track.

June 5, 2019June 5, 2019 by Matt Williams

A double asteroid came uncomfortably close this weekend. Here’s what astronomers saw

The unique capabilities of the SPHERE instrument on ESO’s Very Large Telescope have enabled it to obtain the sharpest images of a double asteroid as it flew by Earth on 25 May. While this double asteroid was not itself a threatening object, scientists used the opportunity to rehearse the response to a hazardous Near-Earth Object (NEO), proving that ESO’s front-line technology could be critical in planetary defence. This artist’s impression shows both components of the double asteroid 1999 KW4 during its Earth fly-by.

On May 25th, 2019, a strange, double-asteroid (1999 KW4) flew past Earth at a distance and speed that is likely to make a lot of people nervous. As always, there was no danger, since the asteroid passed Earth at a minimum distance of 5.2 million km (3.23 million mi), over 15 times greater than the distance between Earth of the Moon, and its orbit is well-understood by scientists.

Because of this, flyby was the perfect opportunity for the International Asteroid Warning Network (IAWN) to conduct a cross-organizational observing campaign of the asteroid 1999 KW4 as it flew by Earth. The European Southern Observatory (ESO) took part in this campaign and managed to capture some images of the object using the Very Large Telescope (VLT).

April 2, 2019April 2, 2019 by Evan Gough

Ground-Based Telescope Directly Observes the Atmosphere of an Extrasolar Planet, and Sees Swirling Clouds of Iron and Silicates

An artist's illustration of the exoplanet HR8799e. The ESO's GRAVITY instrument on its Very Large Telescope Interferometer made the first direct optical observation of this planet and its atmosphere. Image Credit: ESO/L. Calçada

We’ve finally got our first optical look at an exoplanet and its atmosphere, and boy is it a strange place. The planet is called HR8799e, and its atmosphere is a complex one. HR8799e is in the grips of a global storm, dominated by swirling clouds of iron and silicates.

March 15, 2019March 15, 2019 by Evan Gough

Do You See the “Cosmic Bat” in NGC 1788?

The Cosmic Bat in NGC 1788. Image Credit: ESO

2,000 light years away, in the Orion constellation, lurks an eerie looking creature, made of glowing gas lit up by young stars: the Cosmic Bat.

Its real name is NGC 1788. It’s a reflection nebula, meaning the light of nearby stars is strong enough to light it up, but not strong enough to ionize the gas, like in an emission nebula. Even though the stars are young and bright, the Cosmic Bat is still hidden. It took the powerful Very Large Telescope (VLT) to capture this image.

December 19, 2018 by Evan Gough

The Saturn Nebula Kind of Looks Like the Planet in a Small Telescope, But in One of the Most Powerful Telescopes on Earth, it Looks Like This

The Saturn nebula as imaged by the MUSE instrument on the ESO's Very Large Telescope. Image Credit: ESO/VLT

Saturn is an icon. There’s nothing else like it in the Solar System, and it’s something even children recognize. But there’s a distant object that astronomers call the Saturn nebula, because from a distance it resembles the planet, with its pronounced ringed shape.

The Saturn nebula bears no relation to the planet, except in shape. It’s about five thousand light years away, so in a small backyard telescope, it does resemble the planet. But when astronomers train large telescopes on it, the illusion falls apart.

Continue reading “The Saturn Nebula Kind of Looks Like the Planet in a Small Telescope, But in One of the Most Powerful Telescopes on Earth, it Looks Like This”

November 22, 2018 by Matt Williams

Massive Triple Star System Creates this Bizarre Swirling Pinwheel of Dust. And it Could be the Site of a Gamma Ray Burst

The VISIR instrument on ESO’s VLT captured this stunning image of a newly-discovered massive binary star system. Nicknamed Apep after an ancient Egyptian deity, it could be the first gamma-ray burst progenitor to be found in our galaxy. Apep’s stellar winds have created the dust cloud surrounding the system, which consists of a binary star with a fainter companion. With 2 Wolf-Rayet stars orbiting each other in the binary, the serpentine swirls surrounding Apep are formed by the collision of two sets of powerful stellar winds, which create the spectacular dust plumes seen in the image. The reddish pinwheel in this image is data from the VISIR instrument on ESO’s Very Large Telescope (VLT), and shows the spectacular plumes of dust surrounding Apep. The blue sources at the centre of the image are a triple star system — which consists of a binary star system and a companion single star bound together by gravity. Though only two star-like objects are visible in the image, the lower source is in fact an unresolved binary Wolf-Rayet star. The triple star system was captured by the NACO adaptive optics instrument on the VLT. Credit: ESO/Callingham et al.

When stars reach the end of their lifespan, many undergo gravitational collapse and explode into a supernova, In some cases, they collapse to become black holes and release a tremendous amount of energy in a short amount of time. These are what is known as gamma-ray bursts (GRBs), and they are one of the most powerful events in the known Universe.

Recently, an international team of astronomers was able to capture an image of a newly-discovered triple star system surrounded by a “pinwheel” of dust. This system, nicknamed “Apep”, is located roughly 8,000 light years from Earth and destined to become a long-duration GRB. In addition, it is the first of its kind to be discovered in our galaxy.

Continue reading “Massive Triple Star System Creates this Bizarre Swirling Pinwheel of Dust. And it Could be the Site of a Gamma Ray Burst”

November 16, 2018March 23, 2019 by Matt Williams

Super Earth Planet Found Around One of the Closest Stars to us. But it’s Probably a Terrible Place to Live

The nearest single star to the Sun hosts an exoplanet at least 3.2 times as massive as Earth — a so-called super-Earth. Data from a worldwide array of telescopes, including ESO’s planet-hunting HARPS instrument, have revealed this frozen, dimly lit world. The newly discovered planet is the second-closest known exoplanet to the Earth and orbits the fastest moving star in the night sky. This image shows an artist’s impression of the planet’s surface. Credit: ESO

In the course of searching for extra-solar planets, some very interesting finds have been made. Some of them have even occurred within our own galactic neighborhood. Just two years ago, astronomers from the Red Dots and CARMENES campaigns announced the discovery of Proxima b, a rocky planet that orbits within the habitable zone of our nearest stellar neighbor – Proxima Centauri.

This rocky world, which may be habitable, remains the closest exoplanet ever discovered to our Solar System. A few days ago (on Nov. 14th), Red Dots and CARMENES announced another find: a rocky planet orbiting Barnard’s star, which is just 6 light years from Earth. This planet, Barnard’s Star b, is now the second closest exoplanet to our Solar System, and the closest planet to orbit a single star.

Continue reading “Super Earth Planet Found Around One of the Closest Stars to us. But it’s Probably a Terrible Place to Live”

November 13, 2018 by Matt Williams

Direct Observations of a Planet Orbiting a Star 63 Light-Years Away

This artist’s view shows the planet orbiting the young star Beta Pictoris. This exoplanet is the first to have its rotation rate measured. Its eight-hour day corresponds to an equatorial rotation speed of 100 000 kilometres/hour — much faster than any planet in the Solar System.

In the past thirty years, the number of planets discovered beyond our Solar System has grown exponentially. Unfortunately, due to the limitations of our technology, the vast majority of these exoplanets have been discovered by indirect means, often by detecting the transits of planets in front of their stars (the Transit Method) or by the gravitational influence they exert on their star (the Radial Velocity Method).

Very few have been imaged directly, where the planets have been observed in visible light or infrared wavelengths. One such planet is Beta Pictoris b, a young massive exoplanet that was first observed in 2008 by a team from the European Southern Observatory (ESO). Recently, the same team tracked this planet as it orbited its star, resulting in some stunning images and an equally impressive time-lapse video.

Continue reading “Direct Observations of a Planet Orbiting a Star 63 Light-Years Away”

November 6, 2018 by Matt Williams

Astronomers Get as Close as They Can to Seeing the Black Hole at the Heart of the Milky Way

This visualization uses data from simulations of orbital motions of gas swirling around at about 30% of the speed of light on a circular orbit around the black hole. Credit: ESO/Gravity Consortium/L. Calçada

Since the 1970s, astronomers have theorized that at the center of our galaxy, about 26,000 light-years from Earth, there exists a supermassive black hole (SMBH) known as Sagittarius A*. Measuring an estimated 44 million km (27.3 million mi) in diameter and weighing in at roughly 4 million Solar masses, this black hole is believed to have had a profound influence on the formation and evolution of our galaxy.

And yet, scientists have never been able to see it directly and its existence has only been inferred from the effect it has on the stars and material surrounding it. However, new observations conducted by the GRAVITY collaboration** has managed to yield the most detailed observations to date of the matter surrounding Sagittarius A*, which is the strongest evidence yet that a black hole exists at the center of the Milky Way. Continue reading “Astronomers Get as Close as They Can to Seeing the Black Hole at the Heart of the Milky Way”