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This NASA/ESA Hubble Space Telescope images showcases the galaxy NGC 2217.ESA/Hubble & NASA, J. Dalcanton; Acknowledgement: Judy Schmidt (Geckzilla)

The magnificent central bar of NGC 2217 (also known as AM 0619-271) shines bright in the constellation of Canis Major (The Greater Dog), in this image taken by the NASA/ESA Hubble Space Telescope. Roughly 65 million light-years from Earth, this barred spiral galaxy is a similar size to our Milky Way at 100,000 light-years across. Many stars are concentrated in its central region forming the luminous bar, surrounded by a set of tightly wound spiral arms.

The central bar in these types of galaxies plays an important role in their evolution, helping to funnel gas from the disk into the middle of the galaxy. The transported gas and dust are then either formed into new stars or fed to the supermassive black hole at the galaxy’s center. Weighing from a few hundred to over a billion times the mass of our Sun, supermassive black holes are present in almost all large galaxies.

This image was colorized with data from the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS).

Text credit: European Space Agency (ESA)

Media Contact:

Claire Andreoli
NASA’s Goddard Space Flight Center, Greenbelt, MD
claire.andreoli@nasa.gov

Before it shattered over Germany, the asteroid 2024 BX1 was clocked rotating once every 2.6 seconds – the fastest spin we have observed

arXiv:2401.08767v2 Announce Type: replace Abstract: Understanding stellar evolution and its effect on planetary systems is crucial for correctly interpreting the chemical constraints of exo-planetary material that can be given to us by white dwarfs. This article will describe how asteroids, moons, and comets, as well as boulders, pebbles and dust, evolve into eventual targets for chemical spectroscopy, and how planets and companion stars play a vital role in reshaping system architectures for this purpose.

The Conditions for Warping and Breaking Protoplanetary Discs

The study of warped discs was once limited to the viscous accretion discs around black holes. Now, high resolution observations indicate that the warping and breaking of protoplanetary discs is not uncommon and there is growing interest from the planet formation community in these effects. Warping and breaking alter the evolution of the disc, for example by enhancing the accretion rate and changing the chemical composition. However, our understanding of the conditions under which protoplanetary discs warp and/or tear remains far more limited than for black hole discs. I will present the conclusions from our high-resolution simulations and discuss what factors affect whether and where a protoplanetary disc will break and how this differs from the commonly referenced theoretical predictions. Finally, I will share some examples of observed disc systems that we still can’t explain and suggest avenues for future research.

• Speaker: Alison Young (Edinburgh)
• Monday 29 April 2024, 14:00-15:00
• Venue: MR14 DAMTP and online.
• Series: DAMTP Astrophysics Seminars; organiser: Roger Dufresne.

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arXiv:2404.15427v1 Announce Type: new Abstract: This review is focused on describing the logic by which we make predictions of exoplanetary compositions and mineralogies, and how these processes could lead to compositional diversity among rocky exoplanets. We use these predictions to determine the sensitivity of present-day and future observations to detecting compositional differences between rocky exoplanets and the four terrestrial planets. First, we review data on stellar abundances and infer how changes in composition may manifest themselves in the expected bulk compositions of rocky exoplanets (section 2). Converting this information in mass-radius relationships requires calculation of the stable mineral assemblages at a given temperature-pressure-composition (T-P-X), an exercise we describe in section 3. Should the planet be hot enough to engender partial melting of the mantle, then these liquids are likely to rise to the surface and erupt to form planetary crusts; the possible compositional and mineralogical variability of which we examine in section 4. Finally, the expected spectroscopic responses of such crusts are examined in section 5.

arXiv:2404.15425v1 Announce Type: new Abstract: White dwarf planetary systems provide a unique way to measure the bulk composition of exoplanetary material. Extrasolar asteroids/comets/moons which have survived the evolution of their host star can end up in the atmosphere of the white dwarf. Asteroids and boulders appear to be the most common pollutants, where we use the term "asteroids" to refer to the parent body that is polluting the atmosphere. The presence of the planetary material is detected via absorption lines of heavy elements. White dwarfs with these absorption features are called "polluted" white dwarfs. Polluted white dwarfs were expected to be rare objects because white dwarfs have high surface gravities, therefore, these heavy elements will settle out of the white dwarf's atmospheres in a short amount of time (Paquette et al. 1986). However, high-resolution spectroscopic surveys found that 25-50% of white dwarfs are polluted (Zuckerman et al. 2003, 2010; Koester et al. 2014). The mechanism responsible for making a polluted white dwarf must be common and efficient. There is strong theoretical and observational evidence that white dwarfs are accreting from planetary material. There are different mechanisms that can deliver exoplanetary material into the Roche lobe of the white dwarf. Debris disks, transits from disintegrating bodies, and intact planets have all been detected around white dwarfs (e.g., Jura et al. 2007; Vanderburg et al. 2015, 2020). This chapter will describe how the chemical autopsies are conducted, and what is learnt about exoplanetary material from polluted white dwarfs.

arXiv:2404.16512v1 Announce Type: new Abstract: The first stars might have been fast rotators. This would have important consequences for their radiative, mechanical and chemical feedback. We discuss the impact of fast initial rotation on the evolution of massive Population III models and on their nitrogen and oxygen stellar yields. We explore the evolution of Population III stars with initial masses in the range of 9Msol

arXiv:2404.16261v1 Announce Type: new Abstract: Over twenty years ago, Type Ia Supernovae (SNIa) [arXiv:astro-ph/9805201, arXiv:astro-ph/9812133] observations revealed an accelerating Universe expansion, suggesting a significant dark energy presence, often modelled as a cosmological constant, $\Lambda$. Despite its pivotal role in cosmology, the standard $\Lambda$CDM model remains largely underexplored in the redshift range between distant SNIa and the Cosmic Microwave Background (CMB). This study harnesses the James Webb Space Telescope's advanced capabilities to extend the Hubble flow mapping across an unprecedented redshift range, from $z \approx 0$ to $z \approx 7.5$. Utilising a dataset of 231 HII galaxies and extragalactic HII regions, we employ the $\text{L}-\sigma$ relation, correlating the luminosity of Balmer lines with their velocity dispersion, to define a competitive technique for measuring cosmic distances. This approach maps the Universe's expansion over more than 12 billion years, covering 95\% of its age. Our analysis, using Bayesian inference, constrains the parameter space $\lbrace h, \Omega_m, w_0\rbrace = \lbrace 0.731\pm0.039, 0.302^{+0.12}_{-0.069}, -1.01^{+0.52}_{-0.29}\rbrace $ (statistical) for a flat Universe. These results provide new insights into cosmic evolution and suggest uniformity in the photo-kinematical properties of young massive ionizing clusters in giant HII regions and HII galaxies across most of the Universe's history.

The next-generation Event Horizon Telescope: from Still Images to Video.

The next-generation Event Horizon Telescope (ngEHT) is a transformative upgrade to the EHT that will realize black hole “cinema”: real-time and time-lapse movies of supermassive black holes on event horizon scales. These movies will resolve complex structure and dynamics on Schwarzschild radius dimensions, bringing into focus not just the persistent strong-field gravity features predicted by General Relativity (GR), but details of active accretion and relativistic jet launching that drive large scale structure in the Universe. This effort builds upon recent results by the Event Horizon Telescope (EHT): the first image of M87 ’s supermassive black hole and its magnetic field structure, as well as resolved images of SgrA*, the central black hole at the heart of the Milky Way. These images are scientifically rich, and show that evolution of the EHT to a more capable array can address even deeper questions across physics and astronomy. The central concept behind the ngEHT is that the addition of modest-diameter dishes at new geographic locations and multi-color observations over a range of frequencies will enable the next revolution in horizon-resolved black hole studies. This talk will cover the ngEHT technical plans and scientific goals.

• Speaker: Speaker to be confirmed
• Wednesday 01 May 2024, 15:00-16:00
• Venue: Battcock coffee area + ONLINE - Details to be sent by email.
• Series: Kavli Institute for Cosmology Seminars; organiser: Steven Brereton.

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Science, Volume 384, Issue 6694, Page 369-370, April 2024.

A Tokyo company's satellite encounters a big lump of space debris high above the Earth.

Today, Aisén Etcheverry, the Chilean Minister of Science, Technology, Knowledge and Innovation, accompanied by Gonzalo Arenas, the Ministry’s Head of International Relations and Maria Soledad Morales, Chilean Consul to Bavaria and Baden-Wütternberg visited the ESO Headquarters in Garching bei München, Germany. The visit, the first of a Chilean science minister to ESO’s facilities in Germany, provided an opportunity to further strengthen ties between ESO and Chile. The close collaborative relationship between ESO and Chile goes back over 60 years and has allowed the organisation to operate its telescopes at unique observing sites in Chile, while generating business opportunities and contributing to the development of Chilean astronomy. 

The visitors were hosted by ESO Director General, Xavier Barcons, and ESO’s ‎Head of the Executive Office of the Director General & Head of Legal and Institutional Affairs, Laura Comendador Frutos. Following an opening presentation about ESO’s value chain and its societal impact by Barcons, ESO staff gave presentations on topics including technology development, opportunities for industry and science data management at ESO. The Chile delegation later had exchanges with several ESO staff members, including the Chilean staff working at the ESO Headquarters. 

After the presentations, Minister Etcheverry and her delegation were given a tour of the facilities at the Garching site, including a stop at ESO’s Large Integration Hall. This is where some telescope components, including those for the upcoming ESO’s Extremely Large Telescope, are prepared and tested.  

ESO Director General Xavier Barcons said: "Chile has been a partner and host state to ESO for over 60 years, and we are very honoured to welcome Science Minister Etcheverry to our headquarters in Garching. This visit is an exciting opportunity to explore ways to strengthen our international collaboration, for the benefit of both ESO and Chile." 

Minister Aisén Etcheverry said: "Chile is renowned as the global astronomical capital, and behind the remarkable scientific discoveries lies a tremendous amount of engineering, electronics, and digital technologies development that numerous Chilean men and women contribute to. To gain deeper insights into these experiences and prepare for a future joint industry day, we visited the ESO headquarters in Garching to acquire firsthand knowledge of the cutting-edge technological advancements that will undoubtedly hold immense interest for the Chilean industry."

Nature, Published online: 25 April 2024; doi:10.1038/d41586-024-01223-0

The Geologic Atlas of the Lunar Globe doubles the resolution of Apollo-era maps and will support the space ambitions of China and other countries.

The redness of asteroid 469219 Kamo‘oalewa marks it out as probably originating on the moon, and now we might know the exact impact crater it was launched from

The supermassive black holes at the centres of galaxies may capture smaller black holes. Not only does this prove a place for the small black holes to grow, it also makes the supermassive ones look even bigger and brighter

3 min read

Sols 4166-4167: A Garden Full of Rocks This image was taken by Left Navigation Camera onboard NASA’s Mars rover Curiosity on Sol 4164 (2024-04-23 16:43:09 UTC). NASA/JPL-Caltech

Earth planning date: Wednesday April 24, 2024

Here on Earth (in Toronto, specifically), it’s a very typical April which can’t quite make up its mind about whether or not it wants to be spring. On Mars (in Gale Crater), we’re well into spring, and Curiosity is enjoying the (relatively) warmer weather. As the days get longer and the weather gets warmer, I find myself with lots of energy, itching to get outside and play in my garden. Curiosity seems to feel similar – we’ve been flush with power recently, and today’s touch-and-go plan is no exception. This means lots of opportunity for Curiosity to play in its own kind of garden – albeit one a bit less green than my own.

The first sol of the plan starts with contact science on ‘Twin Peaks,’ which is a small, darker block on top of a lighter block (which you can see the edge of in the image above). This is followed by a two hour long science block packed full of ChemCam and Mastcam observations. ChemCam is starting up close with LIBS on ‘Gilber Lake’ (in the centre of the image above) followed by two long distance mosaics of our long-time companions, the upper Gediz Vallis Ridge and Kukenan. Mastcam has its own mosaic of Pinnacle Ridge and then turns its sights to two closer blocks – ‘Hawk’s Head Notch’ and ‘Cleaver Notch.’ We’re then back for more contact science – this time with MAHLI – before driving on towards Pinnacle Ridge. It’s a geology-heavy sol, but the atmosphere and environment science theme group (ENV) will sneak in to take a tau measurement at the end of the sol to keep an eye on the changing atmospheric dust.

As is often the case in these kinds of plans, the second sol is a bit more sedate, but Curiosity will still manage to squeeze in nearly an hour and a half of science. Most of this is given over to environmental monitoring. Because we don’t need to be in a certain location to check out dust and clouds, we can let the geology and minerology science theme group (GEO) have their fun before the drive and save our observations for the ‘untargeted’ portion of the plan. On the dusty side of things, we have another tau as well as a line of sight scan towards the crater rim. A long dust devil movie will look out for dust lifting in the middle distance, and a deck monitoring observation will check out how dust grains on the rover’s deck might have moved. We’re also looking north above the horizon for clouds. GEO isn’t entirely left out of this sol though – they’ll wrap up the plan with a ChemCam AEGIS observation.

Written by Alex Innanen, Atmospheric Scientist at York University

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Details Last Updated Apr 24, 2024 Related Terms

• Blogs
• Curiosity (Rover)
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Nature, Published online: 24 April 2024; doi:10.1038/s41586-024-07285-4

We report observations of GRB 231115A, positionally coincident with the starburst galaxy M82, that unambiguously qualify this burst as a giant flare from a magnetar, which is a rare explosive event releasing gamma rays.

Nature, Published online: 24 April 2024; doi:10.1038/d41586-024-01023-6

Observations have revealed a galaxy that stopped forming stars earlier than expected. This discovery offers clues about when the first galaxies emerged and sheds light on how stars formed when the Universe was in its infancy.

Almost all moon landers break down during the extraordinary cold of lunar night, but Japan’s Smart Lander for Investigating Moon has astonishingly survived three nights

Scientists from the Cambridge University have suggested that molecules vital to the development of life could have formed from a process known as graphitisation. Once verified in the laboratory, the finding could allow scientists to recreate plausible conditions for life's emergence. It has long been debated how the...