Featured Archives

November 12, 2023November 12, 2023 by Matt Williams

Gaia is so Accurate it Can Predict Microlensing Events

ESA/Gaia/DPAC; CC BY-SA 3.0 IGO. Acknowledgement: A. Moitinho.

The ESA’s Gaia Observatory continues its astrometry mission, which consists of measuring the positions, distances, and motions of stars (and the positions of orbiting exoplanets) with unprecedented precision. Launched in 2013 and with a five-year nominal mission (2014-2019), the mission is expected to remain in operation until 2025. Once complete, the mission data will be used to create the most detailed 3D space catalog ever, totaling more than 1 billion astronomical objects – including stars, planets, comets, asteroids, and quasars.

Another benefit of this data, according to a team of researchers led by the Chinese Academy of Sciences (CAS), is the ability to predict future microlensing events. Similar to gravitational lensing, this phenomenon occurs when light from background sources is deflected and amplified by foreground objects. Using information from Gaia‘s third data release (DR3), the team predicted 4500 microlensing events, 1664 of which are unlike any we have seen. These events will allow astronomers to conduct lucrative research into distant star systems, exoplanets, and other celestial objects.

November 11, 2023November 11, 2023 by Matt Williams

An Epic Collaboration Between Hubble and JWST

This panchromatic view of galaxy cluster MACS0416 was created by combining infrared observations from the NASA/ESA/CSA James Webb Space Telescope with visible-light data from the NASA/ESA Hubble Space Telescope. Credit: NASA/ESA/CSA/STScI

In 2012, as part of the MAssive Cluster Survey (MACS), the Hubble Space Telescope (HST) discovered a pair of colliding galaxy clusters (MACS0416) that will eventually combine to form an even bigger cluster. Located about 4.3 billion light-years from Earth, the MACS0416 cluster contains multiple gravitational lenses that allow astronomers to look back in time and view galaxies as they appeared when the Universe was young. In a new collaboration that symbolizes the passing of the torch, the venerable Hubble and the James Webb Space Telescope (JWST) teamed up to conduct an extremely detailed study of MACS0416.

November 9, 2023November 9, 2023 by Matt Williams

Sometimes Compact Galaxies Hide Their Black Holes

Illustration of an active quasar. What role does its dark matter halo play in activating the quasar? Credit: ESO/M. Kornmesser — Illustration of an active quasar. New research shows that SMBHs eat rapidly enough to trigger them. Credit: ESO/M. Kornmesser

Quasars, short for quasi-stellar objects, are one of the most powerful and luminous classes of objects in our Universe. A subclass of active galactic nuclei (AGNs), quasars are extremely bright galactic cores that temporarily outshine all the stars in their disks. This is due to the supermassive black holes in the galactic cores that consume material from their accretion disks, a donut-shaped ring of gas and dust that orbit them. This matter is accelerated to close to the speed of light and slowly consumed, releasing energy across the entire electromagnetic spectrum.

Based on past observations, it is well known to astronomers that quasars are obscured by the accretion disk that surrounds them. As powerful radiation is released from the SMBH, it causes the dust and gas to glow brightly in visible light, X-rays, gamma-rays, and other wavelengths. However, according to a new study led by researchers from the Centre for Extragalactic Astronomy (CEA) at Durham University, quasars can also be obscured by the gas and dust of their entire host galaxies. Their findings could help astronomers better understand the link between SMBHs and galactic evolution.

November 9, 2023November 9, 2023 by Matt Williams

ESA Has a Difficult Choice: Study Mars, Earth's Magnetosphere, or Gamma-Ray Bursts

The space science community has narrowed down the shortlist for ESA’s next ‘medium’ mission to three finalists: M-Matisse, Plasma Observatory and Theseus. Credit: ESA

The European Space Agency (ESA) is looking to the future and contemplating its next M-class (Medium) mission. These missions are crucial to the ESA Science Programme (part of the agency’s Science Directorate), which aims to provide the best tools to ensure Europe’s continued participation in space exploration and sustain its capabilities in space by fostering innovation, maintaining launch services, and spacecraft operations. The latest round began in December 2021, when the ESA called for proposals for the next M-class mission to launch in the mid-2030s.

In a statement issued yesterday (Wednesday, November 8th), the ESA announced that it had narrowed the list of candidates to three concepts. These include the twin M-MATISSE, the seven-spacecraft Plasma Observatory, and the THESEUS satellite. The final selection will assist ESA operations and research in space by studying the evolution and past habitability of Mars, exploring the plasma environment around Earth, or studying powerful transient events across the Universe. The final selection of one mission is expected to happen by mid-2026.

November 6, 2023November 6, 2023 by Matt Williams

Juno Spots Salts and Organic Molecules on Ganymede’s Surface

Enhanced image of Ganymede taken by the JunoCam during the mission's flyby on June 7th, 2021. Credit: NASA/JPL-Caltech/SwRI/MSSS/Kalleheikki Kannisto

NASA’s Juno mission continues to orbit Jupiter, gathering data on its atmosphere, composition, gravitational field, magnetic field, and radiation environment. This data is helping scientists to learn more about the planet’s formation, internal structure, mass distribution, and what is driving its powerful winds. Periodically, the spacecraft also performs flybys of Jupiter’s largest satellites (the Galilean Moons), acquiring stunning images and vital data on their surfaces. These include optical and thermal images of Io’s many active volcanoes, Europa’s icy terrain, and infrared images of Ganymede.

During its last flyby of Ganymede (June 7th, 2021), Juno collected infrared images and spectra on the moon’s surface using its Jovian InfraRed Auroral Mapper (JIRAM) instrument. According to a recent study by an international team of researchers, this data revealed the presence of salt minerals and organic molecules on the icy moon’s surface. The findings could help scientists better understand the origin of Ganymede, the composition of its interior ocean, and the way material is exchanged between the surface and interior. In short, it could help scientists determine if life exists deep inside Ganymede’s ocean.

November 6, 2023November 9, 2023 by Matt Williams

Supermassive Black Holes Shut Down Star Formation During Cosmic Noon

Artist’s impression of a quasar. These all have supermassive black holes at their hearts. Credit: NOIRLab/NSF/AURA/J. da Silva

Since it became operational almost two years ago, the James Webb Space Telescope (JWST) has produced countless breathtaking images of the Universe and enabled fresh insights into how it evolved. In particular, the telescope’s instruments are optimized for studying the cosmological epoch known as Cosmic Dawn, ca. 50 million to one billion years after the Big Bang when the first stars, black holes, and galaxies in the Universe formed. However, astronomers are also getting a better look at the epoch that followed, Cosmic Noon, which lasted from 2 to 3 billion years after the Big Bang.

During this time, the first galaxies grew considerably, most stars in the Universe formed, and many galaxies with supermassive black holes (SMBHs) at their centers became incredibly luminous quasars. Scientists have been eager to get a better look at galaxies dated to this period so they can see how SMBHs affected star formation in young galaxies. Using near-infrared data obtained by Webb, an international team of astronomers made detailed observations of over 100 galaxies as they appeared 2 to 4 billion years after the Big Bang, coinciding with Cosmic Noon.

November 4, 2023November 13, 2023 by Matt Williams

Civilizations Could Use Gravitational Lenses to Transmit Power From Star to Star

A new study shows how Solar Gravitational Lenses (SGLs) could be used to beam power from one system to another.. Credit: NASA/ESA

In 1916, famed theoretical physicist Albert Einstein put the finishing touches on his Theory of General Relativity, a geometric theory for how gravity alters the curvature of spacetime. The revolutionary theory remains foundational to our models of how the Universe formed and evolved. One of the many things GR predicted was what is known as gravitational lenses, where objects with massive gravitational fields will distort and magnify light coming from more distant objects. Astronomers have used lenses to conduct deep-field observations and see farther into space.

In recent years, scientists like Claudio Maccone and Slava Turyshev have explored how using our Sun as a Solar Gravity Lens (SGL) could have tremendous applications for astronomy and the Search for Extratterstiral Intelligence (SETI). Two notable examples include studying exoplanets in extreme detail or creating an interstellar communication network (a “galactic internet”). In a recent paper, Turyshev proposes how advanced civilizations could use stellar gravitational lenses to transmit power from star to star – a possibility that could have significant implications in our search for technosignatures.

November 3, 2023November 3, 2023 by Matt Williams

SETI Works Best When Telescopes Double-Check Each Other

The LOFAR 'superterp', part of the core of the extended telescope located in the Netherlands. Credit: LOFAR/ASTRON

The Search for Extraterrestrial Intelligence (SETI) has evolved considerably in the past sixty years since the first experiment was conducted. This was Project Ozma, which was conducted in 1960 by Dr. Frank Drake and his colleagues using the National Radio Astronomy Observatory (NRAO) in Green Bank, West Virginia. While the experiment did not reveal any radio signals from space, it established the foundation upon which all future SETI is based. Like Ozma, the vast majority of these experiments have searched for possible technosignatures in the radio spectrum.

Unfortunately, this search has always been plagued by the problem of radio interference from Earth-based radio antennas and satellites in orbit, which can potentially flood SETI surveys with false positives. In a recent study, an international team of astronomers (including researchers with Breakthrough Listen) recommended that future technosignature searches rely on multi-site simultaneous observations. This has the potential of eliminating interference from terrestrial sources and narrowing the search for extraterrestrial radio signals.

November 2, 2023November 2, 2023 by David Dickinson

Comet H2 Lemmon Brightens in Early November Ahead of Expectations

Discovered early this year, Comet C/2023 H2 Lemmon may approach naked eye brightness this month.

A comet discovered earlier this year is performing above expectations, and is currently well-placed in the dusk sky. We’re talking about Comet C/2023 H2 Lemmon, moving up the charts now at magnitude +8 and brightening.

October 31, 2023October 31, 2023 by Matt Williams

New Telescopes to Study the Aftermath of the Big Bang

A photograph of a CMB-S4 detector wafer being prepared for testing in a cryostat at Lawrence Berkeley National Laboratory. Credit: Thor Swift/Lawrence Berkeley National Laboratory

Astronomers are currently pushing the frontiers of astronomy. At this very moment, observatories like the James Webb Space Telescope (JWST) are visualizing the earliest stars and galaxies in the Universe, which formed during a period known as the “Cosmic Dark Ages.” This period was previously inaccessible to telescopes because the Universe was permeated by clouds of neutral hydrogen. As a result, the only light is visible today as relic radiation from the Big Bang – the Cosmic Microwave Background (CMB) – or as the 21 cm spectral line created by the reionization of hydrogen (aka. the Hydrogen Line).

Now that the veil of the Dark Ages is being slowly pulled away, scientists are contemplating the next frontier in astronomy and cosmology by observing “primordial gravitational waves” created by the Big Bang. In recent news, it was announced that the National Science Foundation (NSF) had awarded $3.7 million to the University of Chicago, the first part of a grant that could reach up to $21.4 million. The purpose of this grant is to fund the development of next-generation telescopes that will map the CMB and the gravitational waves created in the immediate aftermath of the Big Bang.