Institute of Astronomy

Astronomy News

Hubble Captures a Drifting Galaxy

29 May 2023 - 6:17pm
Portal origin URL: Hubble Captures a Drifting GalaxyPortal origin nid: 487364Published: Friday, May 26, 2023 - 07:00Featured (stick to top of list): noPortal text teaser: The jellyfish galaxy JW39 hangs serenely in this image from the NASA/ESA Hubble Space Telescope.Portal image: Large spiral galaxy at center. Its core surrounded by concentric rings of dark and light dust. Its spiral arms hold grey dust and blue areas of star formation. Part of the arm is drawn out above the galaxy. Dust from the arm trails off to the right.

Lab imitations of the unobservable cosmos can be genuinely insightful

29 May 2023 - 6:15pm

Despite the obvious caveats, physicists are right to use fluids and other physical analogues to search for fresh insights about extreme cosmic phenomena, from black holes to the big bang

25 Years of Fantastic Science and Engineering with ESO’s Very Large Telescope

26 May 2023 - 10:20am

ESO’s Very Large Telescope (VLT), one of the world’s most advanced optical telescopes, celebrates its 25th anniversary today. Over the last two and a half decades, from its home in Chile’s Atacama Desert, the VLT has made a profound impact on our understanding of the Universe, with several remarkable firsts. 

ESO’s VLT is the flagship facility for European ground-based optical astronomy. It consists of four Unit Telescopes with main mirrors 8.2 metres in diameter and four movable 1.8-metre Auxiliary Telescopes that form part of the VLT Interferometer. On 25 May 1998, the Unit Telescope UT1 (Antu) obtained its first images, starting a new era for astronomy.

Since then, astronomers have produced over 10 000 scientific papers using data collected by VLT telescopes, an average of more than one peer-reviewed paper per day. Some of the key research done with the help of the VLT includes studying the supermassive black hole at the centre of the Milky Way and establishing the accelerated expansion of the Universe, both of which resulted in Nobel Prizes. Other key findings include the first direct image of a planet outside our Solar System and the characterisation of the first visible counterpart to a gravitational wave source.

The VLT’s remarkable contributions to science were made possible thanks to its suite of advanced instruments. One of the most versatile and demanded by the astronomical community is the FOcal Reducer and low dispersion Spectrograph (FORS), which can take images of relatively large areas of the sky with very high sensitivity. FORS has in fact taken some of the most iconic astronomical images with the VLT. Another versatile instrument is the Multi Unit Spectroscopic Explorer (MUSE), a powerful spectrograph that allows astronomers to create 3D views of the Universe. The VLT also hosts X-shooter, which can be used to observe a wide range of astronomical objects from the more faint to the very bright ones. GRAVITY, an instrument of the VLT Interferometer, is also particularly unique as it combines the light from four telescopes together and stabilises it, allowing astronomers to pick up minute details in very faint objects.

In addition to its multifaceted instruments, the VLT includes an advanced adaptive optics system to correct for the blurring caused by atmospheric turbulence. Its four-laser system, installed on Unit Telescope 4 (Yepun) and used to excite sodium atoms in the atmosphere, is perhaps the most visible feature of the VLT’s Adaptive Optics Facility. The atoms excited by the lasers emit light that is affected by the atmosphere in the same way as the light emitted by real stars. The emitted light is collected by the telescope and can be used by the adaptive-optics system to measure the distortions introduced by the atmosphere and then to correct for them. This advanced system, combined with the excellent dark-sky conditions of the Atacama Desert, ensure the telescope can obtain extremely sharp images.

Still very much at the forefront of science and engineering, the VLT is expected to continue making key discoveries for years to come. One ongoing improvement is the implementation of a laser guide star on each of the Unit Telescopes 1-3, as part of upgrades to the GRAVITY instrument.

ESO will be celebrating the VLT in its social media channels this week, and stay tuned for ESO’s new Chasing Starlight YouTube show, which will highlight some of the VLT’s top science results in its first episode.

Edit (25 May 2023, 14:00): The first episode of Chasing Starlight dedicated to the VLT is out now.

Jupiter’s lightning has rhythm — just like Earth’s

26 May 2023 - 10:20am

Nature, Published online: 23 May 2023; doi:10.1038/d41586-023-01698-3

Bolts begin as a series of short pulses both on Earth and on its much bigger, gassier neighbour in the Solar System.

LIGO is back — and can now spot more colliding black holes than ever

25 May 2023 - 9:43am

Nature, Published online: 24 May 2023; doi:10.1038/d41586-023-01732-4

The twin gravitational-wave detectors have started a new observation run after a major upgrade.

NASA Scientists Make First Observation of a Polar Cyclone on Uranus

25 May 2023 - 9:42am
Portal origin URL: NASA Scientists Make First Observation of a Polar Cyclone on UranusPortal origin nid: 487311Published: Tuesday, May 23, 2023 - 07:35Featured (stick to top of list): noPortal text teaser: Scientists used ground-based telescopes to get unprecedented views, thanks to the giant planet’s position in its long orbit around the Sun.Portal image: Images use wavelength bands K, Ka, and Q

NASA's Chandra, Webb Combine for Arresting Views

25 May 2023 - 9:42am
Portal origin URL: NASA's Chandra, Webb Combine for Arresting ViewsPortal origin nid: 487316Published: Tuesday, May 23, 2023 - 11:39Featured (stick to top of list): noPortal text teaser: Four composite images deliver dazzling views from NASA's Chandra X-ray Observatory and James Webb Space Telescope of two galaxies, a nebula, and a star cluster. Each image combines Chandra's X-rays — a form of high-energy light — with infrared data from previously released Webb images, both of which are invisible to the unaided eye.Portal image: Composite image of Messier 74, a spiral galaxy similar to the Milky Way.

Astronomers race to observe rare supernova in a nearby galaxy

25 May 2023 - 9:41am

An exploding star spotted in the Pinwheel galaxy, 21 million light years from Earth, offers a rare chance to watch a supernova unfolding in real time

NASA's Hubble Hunts for Intermediate-Sized Black Hole Close to Home

24 May 2023 - 10:04am
Portal origin URL: NASA's Hubble Hunts for Intermediate-Sized Black Hole Close to HomePortal origin nid: 487306Published: Tuesday, May 23, 2023 - 10:00Featured (stick to top of list): noPortal text teaser: Astronomers using Hubble have come up with what they say is some of their best evidence yet for the presence of a rare class of "intermediate-sized" black hole that may be lurking in the heart of the closest globular star cluster to Earth.Portal image: The field is filled with stars against a black background. Stars are more dense at image center and taper off toward the edges. Star colors are mainly white and blue-white with a smattering of large, orangish stars.

A massive quiescent galaxy at redshift 4.658

23 May 2023 - 10:19am

Nature, Published online: 22 May 2023; doi:10.1038/s41586-023-06158-6

A massive quiescent galaxy at redshift 4.658

NASA Extends Nancy Grace Roman Space Telescope Science Operations

22 May 2023 - 10:19am

NASA has awarded a contract extension to the Association of Universities for Research in Astronomy Space Telescope Science Institute in Baltimore for the support services required for the agency’s Nancy Grace Roman Space Telescope Science Operations.

JWST spots biggest plume yet spewing from a moon of Saturn

22 May 2023 - 10:18am

Nature, Published online: 18 May 2023; doi:10.1038/d41586-023-01666-x

The huge watery cloud spurting from Enceladus could carry the ingredients for life farther into space than previously known.

Hubble Peers into a Glistening Star Cluster

22 May 2023 - 10:18am
Portal origin URL: Hubble Peers into a Glistening Star ClusterPortal origin nid: 487237Published: Friday, May 19, 2023 - 07:00Featured (stick to top of list): noPortal text teaser: The densely packed globular cluster NGC 6325 glistens in this image from the NASA/ESA Hubble Space Telescope.Portal image: Dense cluster of bright stars. Its core is to the left and has a distinct group of blue stars. Surrounding the core are stars in warmer colors. They are numerous near the core, becoming more sparse, small, and distant toward the sides of the image.

Damage sidelines Virgo gravitational wave detector

22 May 2023 - 10:14am
Science, Volume 380, Issue 6646, Page 682-682, May 2023.

Atmospheric molecular blobs shape up circumstellar envelopes of AGB stars

18 May 2023 - 11:01am

Nature, Published online: 17 May 2023; doi:10.1038/s41586-023-05917-9

The authors report observations of recently formed dust and molecular gas in the atmosphere of IRC+10°216 and interpret HCN, SiS and SiC2 lines as large convective cells in the photosphere, as seen in Betelgeuse.

The nature of an ultra-faint galaxy in the cosmic dark ages seen with JWST

18 May 2023 - 11:01am

Nature, Published online: 17 May 2023; doi:10.1038/s41586-023-05994-w

The JWST, with the aid of gravitational lensing, confirms the extreme distance of an ultra-faint galaxy at a redshift of 9.79, showing it to have a luminosity typical of the sources responsible for cosmic reionization and highly compact and complex morphology.

A temperate Earth-sized planet with tidal heating transiting an M6 star

18 May 2023 - 11:00am

Nature, Published online: 17 May 2023; doi:10.1038/s41586-023-05934-8

The authors report on a temperate Earth-sized planet orbiting the cool M6 dwarf LP 791-18 with a radius of 1.03 ± 0.04 R⊕ and an equilibrium temperature of 300–400 K, with the permanent night side plausibly allowing for water condensation.

A highly magnetized environment in a pulsar binary system

18 May 2023 - 11:00am

Nature, Published online: 17 May 2023; doi:10.1038/s41586-023-05983-z

The observation of pulsar emission at various orbital phases of a companion star probes the diverse magnetic structure in a binary system, and exhibits varying polarization behavior, akin to that observed in certain fast radio bursts.

Limits on the luminance of dark matter from xenon recoil data

18 May 2023 - 11:00am

Nature, Published online: 17 May 2023; doi:10.1038/s41586-023-05982-0

A direct search for effective electromagnetic interactions between dark matter and xenon nuclei that produce a recoil of the latter is carried out and the first constraint on charge radius of dark matter is derived.

A radio-detected type Ia supernova with helium-rich circumstellar material

18 May 2023 - 11:00am

Nature, Published online: 17 May 2023; doi:10.1038/s41586-023-05916-w

A type Ia supernova shows the presence of helium-rich circumstellar material, as demonstrated by its spectral features, infrared emission and a radio counterpart, that probably originates from a single-degenerate system in which a white dwarf accretes material from a helium donor star.