Astronomy Archives

June 10, 2019June 10, 2019 by Evan Gough

Perfect Example of a Barred Spiral Galaxy, Seen Face On. This is What Our Milky Way Might Look Like

This striking image was taken by the NASA/ESA Hubble Space Telescope’s Wide Field Camera 3, a powerful instrument installed on the telescope in 2009. WFC3 is responsible for many of Hubble’s most breathtaking and iconic photographs, including Pictures of the Week. Shown here, NGC 7773 is a beautiful example of a barred spiral galaxy. A luminous bar-shaped structure cuts prominently through the galaxy's bright core, extending to the inner boundary of NGC 7773's sweeping, pinwheel-like spiral arms. Astronomers think that these bar structures emerge later in the lifetime of a galaxy, as star-forming material makes its way towards the galactic centre — younger spirals do not feature barred structures as often as older spirals do, suggesting that bars are a sign of galactic maturity. They are also thought to act as stellar nurseries, as they gleam brightly with copious numbers of youthful stars. Our galaxy, the Milky Way, is thought to be a barred spiral like NGC 7773. By studying galactic specimens such as NGC 7773 throughout the Universe, researchers hope to learn more about the processes that have shaped — and continue to shape — our cosmic home.

The Hubble Space Telescope has given us a beautiful image of the barred spiral galaxy NGC 7773. This is a classic galaxy of this type, and highlights the bright bar of concentrated stars that anchors the galaxy’s stately spiral arms. It was captured with the Hubble’s workhorse Wide Field Camera 3 (WFC3.)

June 10, 2019December 2, 2019 by Tammy Plotner

Messier 87 – the Virgo A Supergiant Galaxy

M87 and the jet streaming away from its central supermassive black hole. Credits: NASA, ESA and the Hubble Heritage Team (STScI/AURA); Acknowledgment: P. Cote (Herzberg Institute of Astrophysics) and E. Baltz (Stanford University)

Welcome back to Messier Monday! Today, we continue in our tribute to our dear friend, Tammy Plotner, by looking at the supergiant elliptical galaxy known as Messier 87 (aka. Virgo A)!

During the 18th century, famed French astronomer Charles Messier noticed the presence of several “nebulous objects” while surveying the night sky. Originally mistaking these objects for comets, he began to catalog them so that others would not make the same mistake. Today, the resulting list (known as the Messier Catalog) includes over 100 objects and is one of the most influential catalogs of Deep Space Objects.

One of these objects is the supergiant galaxy Messier 87, also known as the Virgo A (or the Smoking Gun) galaxies. Located at a distance of about 53.5 million light years from Earth, this galaxy is home to several trillion stars, 15,000 globular clusters, and a supermassive black hole. It is one of the brightest galaxies in the northern part of the Virgo Cluster, second only to Messier 49, and the dominant member of that group.

Continue reading “Messier 87 – the Virgo A Supergiant Galaxy”

June 10, 2019January 26, 2022 by Matt Williams

New observations from the Planck mission don’t resolve anomalies like the CMB “cold spot”

Cosmic Microwave Background. Scientists compared this to modern galaxy distributions to track dark matter. Copyright: ESA/Planck Collaboration

Back in 2013, the European Space Agency released its first analysis of the data gathered by the Planck observatory. Between 2009 and 2013, this spacecraft observed the remnants of the radiation that filled the Universe immediately after the Big Bang – the Cosmic Microwave Background (CMB) – with the highest sensitivity of any mission to date and in multiple wavelengths.

In addition to largely confirming current theories on how the Universe evolved, Planck’s first map also revealed a number of temperature anomalies – like the CMB “Cold Spot” – that are difficult to explain. Unfortunately, with the latest analysis of the mission data, the Planck Collaboration team has found no new evidence for these anomalies, which means that astrophysicists are still short of an explanation.

June 8, 2019January 26, 2021 by Matt Williams

Black Hole Simulation Solves a Mystery About Their Accretion Disks

Credit: ESA/Hubble, ESO, M. Kornmesser — Researchers at WSU have created a fluid with a negative effective mass for the first time, which could open the door to studying the deeper mysteries of the Universe. Credit: ESA/Hubble, ESO, M. Kornmesse

Black holes are one of the most awesome and mysterious forces in the Universe. Originally predicted by Einstein’s Theory of General Relativity, these points in spacetime are formed when massive stars undergo gravitational collapse at the end of their lives. Despite decades of study and observation, there is still much we don’t know about this phenomenon.

For example, scientists are still largely in the dark about how the matter that falls into orbit around a black hole and is gradually fed onto it (accretion disks) behave. Thanks to a recent study, where an international team of researchers conducted the most detailed simulations of a black hole to date, a number of theoretical predictions regarding accretion disks have finally been validated.

June 6, 2019June 6, 2019 by Evan Gough

There’s a Ring of Cool Gas Wrapped Around the Milky Way’s Supermassive Black Hole

Scientists using ALMA have for the first time captured an image of the cool gas near the black hole in the Milky Way. Image Credit: NRAO/AUI/NSF; S. Dagnello

There’s a lot going on at the center of our galaxy. A supermassive black hole named Sagittarius A-Star resides there, drawing material in with its inexorable gravitational attraction. In that mind-bending neighbourhood, where the laws of physics are stretched beyond comprehension, astronomers have detected a ring of cool gas.

June 5, 2019June 5, 2019 by Matt Williams

A double asteroid came uncomfortably close this weekend. Here’s what astronomers saw

The unique capabilities of the SPHERE instrument on ESO’s Very Large Telescope have enabled it to obtain the sharpest images of a double asteroid as it flew by Earth on 25 May. While this double asteroid was not itself a threatening object, scientists used the opportunity to rehearse the response to a hazardous Near-Earth Object (NEO), proving that ESO’s front-line technology could be critical in planetary defence. This artist’s impression shows both components of the double asteroid 1999 KW4 during its Earth fly-by.

On May 25th, 2019, a strange, double-asteroid (1999 KW4) flew past Earth at a distance and speed that is likely to make a lot of people nervous. As always, there was no danger, since the asteroid passed Earth at a minimum distance of 5.2 million km (3.23 million mi), over 15 times greater than the distance between Earth of the Moon, and its orbit is well-understood by scientists.

Because of this, flyby was the perfect opportunity for the International Asteroid Warning Network (IAWN) to conduct a cross-organizational observing campaign of the asteroid 1999 KW4 as it flew by Earth. The European Southern Observatory (ESO) took part in this campaign and managed to capture some images of the object using the Very Large Telescope (VLT).

June 5, 2019June 5, 2019 by Evan Gough

Astronomers See an Enormous Coronal Mass Ejection… On Another Star!

An illustration of the powerful CME detected coming from OU Andromedae. Image Credit: NASA/CXC/INAF/Argiroffi, C. et al. Illustration: NASA/GSFC/S. Wiessinger

For the first time ever, astronomers have witnessed a coronal mass ejection (CME) on a star other than our very own Sun. The star, named HR 9024 (and also known as OU Andromeda,) is about 455 light years away, in the constellation Andromeda. It’s an active, variable star with a strong magnetic field, which astronomers say may cause CMEs.

“This result, never achieved before, confirms that our understanding of the main phenomena that occur in flares is solid.”
Costanza Argiroffi, Lead Author, University of Palermo, and Associate Researcher at the National Institute for Astrophysics in Italy.

June 5, 2019June 5, 2019 by Evan Gough

Astronomers See Adorable Baby Planets Forming Around a Young Star

This artist's illustration shows two gas giant exoplanets orbiting the young star PDS 70. These planets are still growing by accreting material from a surrounding disk. In the process, they have gravitationally carved out a large gap in the disk. The gap extends from distances equivalent to the orbits of Uranus and Neptune in our solar system. Image Credit: J. Olmsted (STScI)

370 light years away from us, a solar system is making baby planets. The star at the center of it all is young, only about 6 million years old. And its babies are two enormous planets, likely both gas giants, nursing on gaseous matter from the star’s circumsolar disk.

June 5, 2019June 5, 2019 by David Dickinson

Is Jupiter’s Great Red Spot Vanishing as We Near Opposition 2019?

The changing face of Jupiter during opposition 2019. Image credit and copyright: Sharin Ahmad

Jupiter opposition season is nigh, and with it, the largest planet in our solar system and its iconic Great Red Spot present us with a key mystery.

Jupiter in 2019

Jupiter reaches opposition for 2019 on June 10^th. For an outer planet with an orbit exterior to the Earth, opposition simply means it’s ‘opposite’ to the Sun as seen from our Earthly vantage point. This means that Jupiter will rise in the east and dominate the sky throughout the June night, after the Sun sets in the west.

June 3, 2019June 3, 2019 by Matt Williams

NASA is building up a map of the entire sky seen in X-rays, line by line with its NICER experiment

X-ray data recorded by NASA's NICER instrument aboard the ISS. Credits: NASA/NICER

In June of 2017, NASA’s Neutron Star Interior Composition Explorer (NICER) was installed aboard the International Space Station (ISS). The purpose of this instrument is to provide high-precision measurements of neutron stars and other super-dense objects that are on the verge of collapsing into black holes. NICER is also be the first instrument designed to test technology that will use pulsars as navigation beacons.

Recently, NASA used data obtained from NICER’s first 22 months of science operations to create an x-ray map of the entire sky. What resulted was a lovely image that looks like a long-exposure image of fire dancers, solar flare activity from hundreds of stars, or even a visualization of the world wide web. But in fact, each bright spot represents an x-ray source while the bright filaments are their paths across the night sky.