Space and astronomy news
In 1840 an unassuming star in the Southern Hemisphere brightened suddenly. What had been a 5th magnitude star became so bright by 1843 that it was the second brightest star in the sky. The star, known as Eta Carinae, had been known to vary in brightness before, but this change was so sudden and so dramatic that it became known as the Great Eruption.
Continue reading “What Caused Eta Carinae’s 1840 “Great Eruption?””
One of the miracles of modern astronomy is the ability to ‘see’ wavelengths of light that human eyes can’t. Last week, astronomers put that superpower to good use and released five new images showcasing the universe in every wavelength from X-ray to infrared.
Combining data from both Earth- and ground-based telescopes, the five images reveal a diverse set of astronomical phenomena, including the galactic centre, the death throes of stars, and distant galaxies traversing the cosmos.
Continue reading “A Collection of New Images Reveal X-Rays Across the Universe”
New images that combine data from NASA’s Chandra X-ray Observatory and the James Webb Space Telescope (JWST) JWST have just been released! The images feature four iconic astronomical objects, showcasing the capabilities of these observatories by combining light in the visible, infrared, and X-ray wavelengths. These include the NGC 346 star cluster located in the Small Magellanic Cloud (SMC), the NGC 1672 spiral galaxy, the Eagle Nebula (Messier 16, or M16), and the spiral galaxy Messier 74 (aka. the Phantom Galaxy).
These objects were made famous by the venerable Hubble Space Telescope, which took pictures of them between 1995 and 2005. Since it commenced operations, the JWST has conducted follow-up observations that provided a sharper view of these objects that captured additional features. Hubble and the JWST even teamed up to provide a multi-wavelength view of the Phantom Galaxy last year. By adding Chandra’s famed X-ray imaging capabilities to Webb’s sensitivity and infrared light, these latest images provide a new glimpse of these objects, revealing both faint and more energetic and powerful features.
Continue reading “Chandra and JWST Join Forces in a Stunning Series of Images”
Located about 6,500 light-years away in the constellation Taurus resides one of the best-studied cosmological objects known as the Crab Nebula (aka. Messier 1). Originally discovered in the 18th century by English astronomer John Bevis in 1731, the Crab Nebula became the first object included by astronomer Charles Messier in his catalog of Deep Sky Objects. Because of its extreme nature, scientists have been studying the Crab Nebula for decades to learn more about its magnetic field, its high-energy emissions (x-rays), and how these accelerate particles to close to the speed of light.
Astronomers have been particularly interested in studying the polarization of the x-rays produced by the pulsar and what that can tell us about the nebula’s magnetic field. When studies were first conducted in the 1970s, astronomers had to rely on a sounding rocket to get above Earth’s atmosphere and measure the polarization using special sensors. Recently, an international team of astronomers used data obtained by NASA’s Imaging X-ray Polarimetry Explorer (IXPE) to create a detailed map of the Crab Nebula’s magnetic field that has resolved many long-standing mysteries about the object.
Continue reading “The Crab Nebula Looks Completely Different in X-Rays, Revealing its Magnetic Fields”
Over 13 billion years ago, the first galaxies in the Universe formed. They were elliptical, with intermediate black holes (IMBHs) at their centers surrounded by a halo of stars, gas, and dust. Over time, these galaxies evolved by flattening out into disks with a large bulge in the middle. They were then drawn together by mutual gravitational attraction to form galaxy clusters, massive collections that comprise the large-scale cosmic structure. This force of attraction also led to mergers, where galaxies and their central black holes came together to create larger spiral galaxies with central supermassive black holes (SMBHs).
This process of mergers and assimilation (and their role in galactic evolution) is still a mystery to astronomers today since much of it took place during the early Universe, which is still very difficult to observe with existing telescopes. Using data from NASA’s Chandra X-ray Observatory and the International Gemini Observatory, an international team of astronomers observed a lone distant galaxy that appears to have consumed all of its former companions. Their findings, which recently appeared in The Astrophysical Journal, suggest galaxies in the early Universe grew faster than previously thought.
Continue reading “A Distant Galaxy Ate All of its Friends. Now It’s All Alone”
Estimating stellar age has always been a challenge for astronomers. Now, a certain class of exoplanets is making the process even more complicated. Hot Jupiters – gas giants with orbital periods smaller than that of Mercury – appear to have an anti-aging effect on their stars, according to a new study. These enormous planets inflict both magnetic and tidal interference on their host star, speeding up the star’s rotation and causing them to emit X-rays more energetically, both of which are hallmarks of stellar youth. The result calls into question some of what we previously believed about stellar age, and offers a glimpse at the ongoing interconnectivity between a star and its planets long after their formation.
Continue reading “Planets Make it Harder to Figure out a Star’s age”
NASA scientist have released images combining the early data from the James Webb Space Telescope with X-ray data taken with the Chandra Observatory. Besides their beauty, the images offer insights into the inner workings of some of the most complex astrophysical phenomena in the universe.
Continue reading “Chandra’s X-ray Vision Combined With JWST Reveals Even More Details About the Universe”
Cassiopeia A is the remnant of a supernova that exploded 11,000 light-years away. The light from the exploding star likely reached Earth around 1670 (only a couple of years before Newton invented the reflecting telescope.) But there are no records of it because the optical light didn’t reach Earth.
The Cass A nebula ripples with energy and light from the ancient explosion and is one of the most-studied objects in deep space. It’s an expanding gas shell blasted into space when its progenitor star exploded.
But Cass A isn’t expanding evenly, and astronomers think they know why.
Continue reading “Supernova Remnant Cassiopeia A is Lopsided”
Why is there so much antimatter in the Universe? Ordinary matter is far more plentiful than antimatter, but scientists keep detecting more and more antimatter in the form of positrons. More positrons reach Earth than standard models predict. Where do they come from?
Scientists think pulsars are one source, and a new study strengthens that idea.
Continue reading “A Pulsar is Blasting out Jets of Matter and Antimatter”
Not that long ago,, astronomers weren’t sure that exoplanets even existed. Now we know that there are thousands of them and that most stars probably harbour exoplanets. There could be hundreds of billions of exoplanets in the Milky Way, by some estimates. So there’s no reason to think that stars in other galaxies don’t host planets.
But to find one of those planets in another galaxy? That is a significant scientific achievement.
Continue reading “Astronomers Might Have Found a Planet in Another Galaxy”