Paul M. Sutter, Author at Universe Today

October 19, 2020October 19, 2020 by Paul M. Sutter

The galaxy with 99.99% dark matter isn’t so mysterious any more

Artist rendering of the dark matter halo surrounding our galaxy. For quasars, the dark matter halos are much more massive. Credit: ESO/L. Calçada — Artist rendering of the dark matter halo surrounding our galaxy. Credit: ESO/L. Calçada

The dwarf galaxy known as Dragonfly 44 caused a stir recently: apparently it had way, way more dark matter than any other galaxy. Since this couldn’t be explained by our models of galaxy formation, it seemed like an oddball. But a new analysis reveals that Dragonfly 44 has much less dark matter than previously thought. In short: it’s totally normal.

October 13, 2020October 16, 2020 by Paul M. Sutter

Do Ripples on the Surface of the Sun tell us that a Flare is Coming?

Flares from the sun are some of the nastiest things in the solar system. When the sun flares, it belches out intense X-ray radiation (and sometimes even worse). Predicting solar flares is a tricky job, and a new research paper sheds light on a possible new technique: looking for telltale ripples in the surface of the sun minutes before the blast comes.

October 12, 2020October 16, 2020 by Paul M. Sutter

How to See What’s on the Other Side of a Wormhole Without Actually Traveling Through it

Wormholes are incredibly fascinating objects, but also completely hypothetical. We simply don’t know if they can truly exist in our universe. But new theoretical insights are showing how we may be able to detect a wormhole – from a spray of high-energy particles emitted at the moment of its formation.

October 9, 2020October 9, 2020 by Paul M. Sutter

Matter makes up exactly 31.5±1.3% of the Universe

dark matter shown in blue — This image from the NASA/ESA Hubble Space Telescope shows the galaxy cluster MACS J0416. This is one of six clusters that was studied by the Hubble Frontier Fields programme, which yielded the deepest images of gravitational lensing ever made. Scientists used intracluster light (visible in blue) to study the distribution of dark matter within the cluster.

Weighing the universe is a tricky task, but a team of astronomers have used a clever technique to measure how many galaxy clusters are in the cosmos, and from there come up with a total amount of matter. The answer: 31.5±1.3% of all the energy in the universe.

October 9, 2020October 9, 2020 by Paul M. Sutter

The Solar System has a second plane where objects orbit the Sun

Artist's impression of the ecliptic plane (yellow), and the recently-discovered "empty" ecliptic (blue) in our solar system. (Credit: NAOJ)

Almost all the objects orbiting the sun live in a particular plane, called the ecliptic plane. But a recent analysis of long-period comets reveals a second home, a so-called “empty ecliptic”. And it may be populated with comets dragged there by none other than the gravity of the Milky Way galaxy.

October 2, 2020October 2, 2020 by Paul M. Sutter

What Decides the Shape of Planetary Nebulae? Whatever’s Orbiting a Star When it Dies

This Picture of the Week from the NASA/ESA Hubble Space Telescope shows NGC 5307, a planetary nebula which lies about 10000 light years from Earth. It can be seen in the constellation Centaurus (The Centaur), which can be seen primarily in the southern hemisphere. A planetary nebula is the final stage of a Sun-like star. As such, planetary nebulae allow us a glimpse into the future of our own Solar System. A star like our Sun will, at the end of its life, transform into a red giant. Stars are sustained by the nuclear fusion that occurs in their core, which creates energy. The nuclear fusion processes constantly try to rip the star apart. Only the gravity of the star prevents this from happening. At the end of the red giant phase of a star, these forces become unbalanced. Without enough energy created by fusion, the core of the star collapses in on itself, while the surface layers are ejected outward. After that, all that remains of the star is what we see here: glowing outer layers surrounding a white dwarf star, the remnants of the red giant star’s core. This isn’t the end of this star’s evolution though — those outer layers are still moving and cooling. In just a few thousand years they will have dissipated, and all that will be left to see is the dimly glowing white dwarf.

Planetary nebulae are some of the most beautiful objects in the galaxy, spanning a variety of shapes and sizes. They’re created in the death throes of stars like the sun, and new research sheds light into how they get their distinctive and unique shapes. The answer: anything unlucky enough to orbit that dying star.

October 1, 2020October 1, 2020 by Paul M. Sutter

Astronomers think they’ve found an exoplanet in a galaxy 23 million light-years away

Artist's impression of of Kepler-1649c orbiting around its host star. Credit: NASA’s Ames Research Center/Daniel Rutter

Using a variety of techniques astronomers have successfully identified thousands of exoplanets, which are planets orbiting stars outside of our own solar system. But a new research paper introduces a breakthrough: the first detection of an exoplanet not just in another solar system, but in an entirely different galaxy sitting millions of light years away.

September 23, 2020September 22, 2020 by Paul M. Sutter

Solar Cycle 25 has arrived. Here’s what to expect from the Sun in the coming months and years

The sun goes through a regular 11-year cycle, swinging between periods of dormancy and periods of activity. Scientists from NASA and NOAA have just announced that the sun has just passed its minimum, and will be ramping up in activity over the next few years, meaning that we have entered a new round of the never-ending solar cycle.

September 22, 2020September 22, 2020 by Paul M. Sutter

If dark matter is a particle, it should get inside red giant stars and change the way they behave

This artist’s impression shows the red supergiant star. Using ESO’s Very Large Telescope Interferometer, an international team of astronomers have constructed the most detailed image ever of this, or any star other than the Sun. Credit: ESO/M. Kornmesser

Dark matter makes up the vast majority of matter in the universe, but we can’t see it. At least, not directly. Whatever the dark matter is, it must interact with everything else in the universe through gravity, and astronomers have found that if too much dark matter collects inside of red giant stars, it can potentially cut their lifetimes in half.

September 15, 2020September 15, 2020 by Paul M. Sutter

Extreme galaxies depend on extreme conditions for their formation

The spiral pattern shown by the galaxy NGC 2275 in this image from the NASA/ESA Hubble Space Telescope is striking because of its delicate, feathery nature. Credit: ESA/Hubble & NASA, J. Lee and the PHANGS-HST Team; Acknowledgment: Judy Schmidt (Geckzilla)

Some galaxies are too small, and some galaxies are too big, while others are just right. A new survey of the nearby Virgo cluster has potentially revealed why extreme galaxies are the wrong size, and how they might be connected.