Pic of the Week: Interacting Galaxy Pair

Posted on by onespaceman2000
Image (Credit): Hubble image of colliding galaxies – NGC 169 (bottom) and IC 1559 (top). (ESA/Hubble & NASA, J. Dalcanton, Dark Energy Survey, DOE, FNAL/DECam, CTIO/NOIRLab/NSF/AURA, SDSS)

This week’s image comes again from the Hubble Space Telescope, which is keeping us entertained as the James Webb Space Telescope cycles through its required observations and spins off images from time to time.

While an earlier image appeared to show colliding galaxies, though it was believed to be an optical illusion, the collision above is real. Below is more on the image from the European Space Agency’s (ESA) Hubble site:

Galaxies can merge, collide, or brush past one another — each of which has a significant impact on their shapes and structures. As common as these interactions are thought to be in the Universe, it is rare to capture an image of two galaxies interacting in such a visibly dynamic way. This image, from the NASA/ESA Hubble Space Telescope, feels incredibly three-dimensional for a piece of deep-space imagery. 

The subject of this image is named Arp 282, an interacting galaxy pair that is composed of the Seyfert galaxy NGC 169 (bottom) and the galaxy IC 1559 (top). If you’re interested in learning more about Seyfert galaxies, you can read about the Seyfert galaxy NGC 5728 here. Interestingly, both of the galaxies comprising Arp 282 have monumentally energetic cores, known as active galactic nuclei (AGN), although it is difficult to tell that from this image. This is actually rather fortunate, because if the full emission of two AGNs was visible in this image, then it would probably obscure the beautifully detailed tidal interactions occurring between NGC 169 and IC 1559. Tidal forces occur when an object’s gravity causes another object to distort or stretch. The direction of the tidal forces will be away from the lower-mass object and towards the higher mass object. When two galaxies interact, gas, dust and even entire solar systems will be drawn away from one galaxy towards the other by these tidal forces. This process can actually be seen in action in this image — delicate streams of matter have formed, visibly linking the two galaxies.

Astronomy Ideas on Borrowed Time?

Posted on by onespaceman2000
Image (Credit): The position of our Sun as it orbits the Milky Way’s center. (Stefan Payne-Wardenaar)

A recent Big Think story, “5 Consensus Ideas in Astronomy That Might Soon be Overturned,” comes as a good time as we reach further into space and back into time using the James Webb Space Telescope (JWST) and contemplate other telescopes that should come online shortly.

The story highlights these five ideas:

  • Dark energy is a cosmological constant;
  • Stars predate black holes;
  • Jovian planets protect terrestrial ones;
  • Most of the galaxy is uninhabitable; and
  • Globular clusters are planet-free.

For instance, regarding the uninhabitable areas of the galaxy, the Big Think story states:

Among its many discoveries, the ESA’s Gaia mission has found that the Milky Way galaxy not only has a warp to its galactic disk, but that the warp in the disk precesses and wobbles, completing a full rotation for roughly every three revolutions of the Sun [shown in yellow above] around the galactic center. Most astronomers assume that regions with too many stellar cataclysms in them, like the centers of galaxies, may be completely uninhabitable. But this picture is far from certain.

It is worth reading through the list and keeping these ideas in mind, and then following the JWST stories as they unfold. I bet you will be able to make a much longer list as old consensus ideas come apart and new ideas quickly follow.

Pic of the Week: Spiraling Optical Illusion

Posted on by onespaceman2000
Image (Credit): Two spiral galaxies about 1 billion light-years away captured by the Hubble. (European Space Agency)

This week’s fascinating image from the NASA/ESA Hubble Space Telescope shows what appears to be two colliding spiral galaxies. A cropped version is shown below to highlight the colors. Here is more from ESA:

The two galaxies, which have the uninspiring names SDSS J115331 and LEDA 2073461, lie more than a billion light-years from Earth. Despite appearing to collide in this image, the alignment of the two galaxies is likely just by chance — the two are not actually interacting. While these two galaxies might simply be ships that pass in the night, Hubble has captured a dazzling array of interacting galaxies in the past.

Pic of the Week: A Variety of Galaxies

Posted on by onespaceman2000
Image (Credit): Multiple galaxies captured by the NASA/ESA Space Telescope – noted below. (ESA/Hubble & NASA, W. Keel)

With all the excitement about the James Webb Space Telescope, let’s not forget about the ongoing great work being performed by the Hubble Space Telescope. This recently released Hubble image shows multiple galaxies as well as multiple types of galaxies.

Here is a full description from the European Space Agency:

This luminescent image features multiple galaxies, perhaps most noticeably LEDA 58109, the lone galaxy in the upper right. LEDA 58109 is flanked by two further galactic objects to its lower left — an active galactic nucleus (AGN) called SDSS J162558.14+435746.4 that partially obscures the galaxy SDSS J162557.25+435743.5, which appears to poke out to the right behind the AGN. 

Galaxy classification is sometimes presented as something of a dichotomy: spiral and elliptical. However, the diversity of galaxies in this image alone highlights the complex web of galaxy classifications that exist, including galaxies that house extremely luminous AGNs at their cores, and galaxies whose shapes defy the classification of either spiral or elliptical. 

Space Stories: Black Holes, X-Rays, and Exploding Stars

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Image (Credit): Animation showing a binary system of a large, hot blue star and a black hole orbiting each other. (ESO/L.Calçada)

Here are some recent stories of interest.

—SciTechDaily.com: “Astronomers Have Discovered an Especially Sneaky Black Hole“

VFTS 243 is a binary system, which means it is composed of two objects that orbit a common center of mass. The first object is a very hot, blue star with 25 times the mass of the Sun, and the second is a black hole nine times more massive than the Sun. VFTS 243 is located in the Tarantula Nebula within the Large Magellanic Cloud, a satellite galaxy of the Milky Way located about 163,000 light-years from Earth.

—SpaceNews.com: “ESA Scaling Back Design of X-ray Astronomy Mission“

Faced within increasing costs, the European Space Agency is looking for ways to revise the design of a large X-ray space telescope, an effort that could have implications for NASA’s own astrophysics programs…That effort will involve potential changes to its instrument configuration as well as creation of a science “redefinition” team to reconsider science objectives. The goal will be to develop a revised concept, called a minimum disrupted mission, that will cost ESA no more than 1.3 billion euros but still perform science expected of a flagship-class mission.

—NASA.gov: “NASA Rocket Mission Using ‘Astronomical Forensics’ to Study Exploded Star“

A NASA-funded sounding rocket mission will observe the remnants of an exploded star, uncovering new details about the eruption event while testing X-ray detector technologies for future missions. The High-Resolution Microcalorimeter X-ray Imaging, or Micro-X, experiment will launch Aug. 21 from the White Sands Missile Range in New Mexico. The mission’s target of study is some 11,000 light-years away from Earth, off the edge of the W-shaped constellation known as Cassiopeia. There, a massive bubble of radiant material known as Cassiopeia A, or Cas A for short, marks the site of a brilliant stellar death.