Mark Thompson, Author at Universe Today

July 13, 2024July 13, 2024 by Mark Thompson

Mapping the Stars in a Dwarf Galaxy to Reveal its Dark Matter

Dark matter is curious stuff! As the name suggests, it’s dark making it notoriously difficult to study. Although it’s is invisible, it influences stars in a galaxy through gravity. Now, a team of astronomers have used the Hubble Space Telescope to chart the movements of stars within the Draco dwarf galaxy to detect the subtle gravitational pull of its surrounding dark matter halo. This 3D map required studying nearly two decades of archival data from the Draco galaxy. They found that dark matter piles up more in the centre, as predicted by cosmological models.

July 13, 2024July 13, 2024 by Mark Thompson

A Close Pulsar Measures 11.4 km Across

Animation of the millisecond pulsar PSR J0437-4715. On the left as seen from Earth. On the right as seen from the star's equatorial plane. (c) NASA/Sharon Morsink/Devarshi Choudhury et al.

When massive stars detonate as supernovae, they leave often behind a pulsar. These fast rotating stellar corpses have fascinated scientists since their discovery in 1967. One nearby pulsar turns 174 times a second and now, its size has been precisely measured. An instrument on board the International Space Station was used to measure x-ray pulses from the star. A supercomputer was then used to analyse its properties and found it was 1.4 times the mass of the Sun and measured only 11.4 km across!

July 9, 2024July 9, 2024 by Mark Thompson

Do Planets Have the Raw Ingredients for Life? The Answer is in their Stars

Finding planets that already have, or have the ingredients for intelligent life is a real challenge. It is exciting that new telescopes and spacecraft are in development that will start to identify candidate planets. Undertaking these observations will take significant amounts of telescope time so we need to find some way to prioritise which ones to look at first. A new paper has been published that suggests we can study the host stars first for the necessary raw elements giving a more efficient way to hunt for similar worlds to Earth.

July 9, 2024July 9, 2024 by Mark Thompson

The Rugged Desert Moss Best Equipped to Survive on Mars

For decades, we have seen Mars as a desolate landscape devoid of any signs of life. Attempt to identify ways of growing plants and food on the red planet have focussed on greenhouse like structures to enable plants to survive, that is, until now! A desert moss called ‘Syntrichia caninervis’ has been identified and it can grown in extreme environments like Antarctica and the Mojave Desert. A new study revealed the moss can survive Mars-like environments too including low temperatures, high levels of radiation and drought.

July 8, 2024July 8, 2024 by Mark Thompson

Mapping the Milky Way’s Dark Matter Halo

The Galactic disk warp "dances gracefully" under the torque of the dark matter halo (an artistic impression created by Kaiyuan Hou and Zhanxun Dong from the School of Design, Shanghai Jiao Tong University).

Anytime astronomers talk of mapping the Milky Way I am always reminded how tricky the study of the Universe can be. After all, we live inside the Milky Way and working out what it looks like or mapping it from the inside is not the easiest of missions. It’s one thing to map the visible matter but mapping the dark matter is even harder. Challenges aside, a team of astronomers think they have managed to map the dark matter halo surrounding our Galaxy using Cepheid Variable stars and data from Gaia.

July 8, 2024July 8, 2024 by Mark Thompson

Ammonites Were Doing Fine Until the Asteroid Hit

Ammonites basking under the Late Cretaceous sun. Artwork by Callum Pursall (@cpursall on X)

I must confess, I think asteroids and I think of movies like Deep Impact or Armageddon! Scientists think that an asteroid like the ones that appeared in the Hollywood blockbusters struck Mexico 66 million years ago and led to the extinction of the dinosaurs. It now seems they may not have been the only ones that were wiped from our planet. Ammonites are marine mollusks that flourished for 350 million years but they were wiped out too. Some research suggests they were struggling in North America but thriving in other parts of the world.

June 30, 2024June 30, 2024 by Mark Thompson

What’s Next for the Event Horizon Telescope? Twelve Possible New Targets

Both the Milky Way and a galaxy known as M87 have supermassive black holes at their core. These are the two largest black holes we know about and the Event Horizon Telescope has just captured stunning images of their event horizons. A new paper looks at what we might expect from a next generation EHT and highlights twelve targets that should be top of the list.

June 30, 2024June 30, 2024 by Mark Thompson

Merging Galaxies Make for Explosive Star Formation

A festive array of bright pinks and blues makes for a remarkable sight in this image captured with the Gemini North telescope, one half of the International Gemini Observatory. Resembling a cloud of cosmic confetti, this image is being released in celebration of Gemini North’s 25th anniversary. NGC 4449 is a prime example of starburst activity caused by the interacting and mingling of galaxies as it slowly absorbs its smaller galactic neighbors.

The Gemini Observatory has unveiled a striking new image that shows star formation within the irregular galaxy NGC 4449. This galaxy is categorised as a “Magellanic-type” galaxy due to its similarities with the Magellanic Clouds, although it is smaller in size. Surrounding NGC 4449 is a halo of smaller dwarf galaxies, two of which are currently merging with it. This merger is causing clouds of gas to collide, fuelling the surge in star formation observed in NGC 4449.

June 29, 2024June 29, 2024 by Mark Thompson

NASA Releases a New 3D Animation of the Lunar Gateway

A detailed 3D animation of NASA's Gateway space station, showcasing its modules and structural components from various angles against the backdrop of deep space. NASA/Bradley Reynolds, Alberto Bertolin

To get to the Moon, NASA is building a Lunar Gateway in orbit to facilitate easier access to the Moon. With construction beginning in 2028 as part of Artemis IV there will be an ongoing programme of enhancements and additions. NASA has now released a fabulous new 3D animation of the Lunar Gateway to showcase what the final Gateway will look like. It includes modules from partner nations and an Orion lunar landers dock to carry astronauts.

June 28, 2024June 28, 2024 by Mark Thompson

Growing Habitats and Furniture in Space Out of Mushrooms

Artist concept depicting a new novel aerospace concept for NIAC Phase III 2024. Credit: Lynn Rothschild

Over the years we have often seen astronauts gently and deftly moving structures into place with their bare hands. Thinks are easy to move in space but getting them there is slightly more tricky and costly. A new piece of research has explored the possibility of growing structures in space based on food substrates. NASA has now awarded a grant to a proposal to investigate further growing structures using fungal mycelial composites, that’s mushrooms to you and I.