A team of astronomers has found what may be the oldest known planetary nebula ever seen, and certainly one of the biggest. These structures are fleeting on a cosmic timescale, so finding one so old is extremely helpful in nailing down what happens as stars die.
Bonus: It was confirmed to be in a bright, nearby stellar cluster, making it far easier to nail down several of its characteristics [link to paper].
A planetary nebula is a huge cloud of gas blown off by a star like the Sun as it ages and dies. Stars generate energy by fusing lighter elements into heavier ones in their cores. They can do this for billions of years, but eventually the usable fuel runs out. This sets off a complicated chain of events, but in a nutshell the core contracts and heats up, while the outer layers of the star expand and cool. The star becomes a red giant, and blows a wind of gas away that eventually depletes it of gas.
The core of the star, dense and hot and exposed to space, is now called a white dwarf. Its so hot it pours out ultraviolet light that excites the gas it previously blew away, which responds by glowing quite literally like a neon sign. Thats the planetary nebula. Over time the expanding gas gets so spread out the ultraviolet light passes right through it, so the nebula fades away. This typically takes a few thousand years, which is the blink of an eye in a stars lifetime.
A few thousand planetary nebulae are known in our galaxy, but most are distant, small, and faint.
RELATED: Crash Course Astronomy: White Dwarfs and Planetary Nebulae
The planetary nebula in question here is called IPHASX J055226.2+323724 lets call it J0552 for short. It was discovered in 2008, right on top of the well-known open cluster M 37. Open clusters are small collections of hundreds or thousands of stars, typically all born at the same time from a single cloud of gas. Thousands are known, and some are close enough to see by the naked eye, like the Pleiades or the Hyades, the latter of which is the V-shaped series of stars that makes up the head of the constellation Taurus the Bull.
I was delighted to read about this planetary nebula because M 37 is one of a few bright open clusters in the constellation of Auriga that are easily seen from a dark site with binoculars. Ive observed it many, many times with my own telescope because its big, bright, and very easy to find.
The nebula J0552 is large on the sky for a planetary nebula, about a tenth of a degree, or a fifth the size of the full Moon on the sky. Its incredibly faint, and only shows up in very deep exposures using filters that block all light except for the reddish hue that comes from glowing hydrogen gas. It appears to be just off-center in M37, well inside the cluster.
The problem here is that space is deep, and things can appear to overlap while being at wildly different distances. Just seeing a nebula coincident in the sky with an open cluster doesnt mean theyre physically associated.
The new work shows that the two are in fact related. One key is finding the planetary nebula central star, the star that cast off the gas in the first place. Thats usually easy for small nebulae, but for big ones, especially in dense fields of stars, it can be difficult. However in this case it wasnt too hard: Young white dwarfs tend to be blue and hot, and theres only one blue star anywhere near the nebula center. Observations indicate it is in fact a white dwarf with a temperature of 100,000C, and its moving through space along with the cluster. These pretty much clinch its membership.
The beauty of this is that we know the clusters distance from us: about 4,700 light-years away. That gives the physical size of the nebula as 10 light-years, which is huge. Most fade away when theyre a fraction of that size.
Using spectra, the astronomers determined the nebular gas is expanding at a rate of about 20 kilometers per second. Knowing its distance and size, that gives an age of the nebula of about 80,000 years, making this the oldest planetary nebula ever seen.
An important relationship in how stars die is how massive the star was at first, and how massive the white dwarf it leaves behind is when the star dies. The central white dwarf star of J0552 has a mass of about 0.6 times that of the Sun now. Using the characteristics of the cluster the astronomers find it started off life with 2.8 times the Suns mass, making it a beefy blue-white star back in the day.
With these numbers in hand, plus the age, size, and chemical composition of the gas determined from spectra, astronomers can learn quite a bit about what happens when stars die. On top of that, only two other planetary nebulae are known in our galaxy that exist in open clusters, so this helps us understand these stellar jewels as well. Interestingly, the other two are large, old, and come from higher mass stars as well. That might be due to a bias: Open clusters disperse over time, so we tend to see them when theyre relatively young. It takes time for a star to die, with higher-mass stars dying first, so of course in a young cluster well likely only see planetary nebulae from more massive stars.
Or it might be telling us something fundamental about the way clusters make stars and how those stars die. That will take a lot more observations, but that first step is finding these cluster nebulae. J0552 is a precious object.
Mind you, our own Sun will follow this path someday. Not for many billions of years, but it too will run out of core fuel, swell up (engulfing the Earth in the process), blow off its outer layers, and form a planetary nebula. Studying these objects means studying ourselves, if our far-distant-future selves. But if we want a complete picture of the Sun and Earth, we need to understand the whole picture, including what happens, and how, eons from now.
Go here to read the rest:
Astronomers find the death cry of a star in a cluster long ago and not so very far away - Syfy
- The rush to return humans to the Moon and build lunar bases could threaten opportunities for astronomy - Yahoo! Voices - June 3rd, 2024 [June 3rd, 2024]
- Hubble Reveals Stunning Galaxy Concealing the Mysteries of Star Formation - The Daily Galaxy --Great Discoveries Channel - June 3rd, 2024 [June 3rd, 2024]
- Best monocular 2024: Spy top models on the market - Space.com - June 3rd, 2024 [June 3rd, 2024]
- The Moon, Mars, and Saturn line up: This Week in Astronomy with Dave Eicher - Astronomy Magazine - June 3rd, 2024 [June 3rd, 2024]
- MUSE Spots Bizarre Stellar Object with Illuminated Protoplanetary Disk - Sci.News - June 3rd, 2024 [June 3rd, 2024]
- Look up to see the parade of planets in June's pre-dawn sky (and bring binoculars) - Astronomy Magazine - June 3rd, 2024 [June 3rd, 2024]
- Astronomers photograph a star resembling a comet - The Universe. Space. Tech - June 3rd, 2024 [June 3rd, 2024]
- Starlink satellites: Facts, tracking and impact on astronomy - Space.com - June 3rd, 2024 [June 3rd, 2024]
- Best binoculars 2024: Top picks for stargazing, wildlife, birding and more - Space.com - June 3rd, 2024 [June 3rd, 2024]
- How we can understand our universe through math - Astronomy Magazine - June 3rd, 2024 [June 3rd, 2024]
- June brings earliest solstice in 228 years, plenty of astronomical sights - UPI News - June 3rd, 2024 [June 3rd, 2024]
- June Astronomy: The Month Brings Bright Planets, Nice Views of the Milky Way and the Summer Solstice - Coachella Valley Independent - June 3rd, 2024 [June 3rd, 2024]
- Astronomers Surprised After Finding Tiny Moon Is Actually Two Tiny Moons in a Trenchcoat - Futurism - June 3rd, 2024 [June 3rd, 2024]
- Astronomy has a bullying and harassment issue: 'Results presented in this report are bleak' - Space.com - May 31st, 2024 [May 31st, 2024]
- WASP-193b: The bizarro, fluffy exoplanet that comes as a surprise - Astronomy Magazine - May 31st, 2024 [May 31st, 2024]
- Next-Generation Radar Will Map Threatening Asteroids - Universe Today - May 31st, 2024 [May 31st, 2024]
- The rush to return humans to the Moon and build lunar bases could threaten opportunities for astronomy - The Conversation - May 31st, 2024 [May 31st, 2024]
- Glimpses of a volcanic world: New telescope images of Jupiter's moon Io rival those from spacecraft - EurekAlert - May 31st, 2024 [May 31st, 2024]
- The Sky This Week from May 31 to June 7: A Jupiter-Mercury conjunction - Astronomy Magazine - May 31st, 2024 [May 31st, 2024]
- Is Pluto a planet? The experts break it down. - Astronomy Magazine - May 31st, 2024 [May 31st, 2024]
- Astronomy Generates Mountains of Data. That's Perfect for AI - Universe Today - May 31st, 2024 [May 31st, 2024]
- The Moon meets Saturn: This Week in Astronomy with Dave Eicher - Astronomy Magazine - May 31st, 2024 [May 31st, 2024]
- What it means for planets to align | Astronomy.com - Astronomy Magazine - May 31st, 2024 [May 31st, 2024]
- The future is bright for astronomy, and very expensive (op-ed) - Space.com - May 31st, 2024 [May 31st, 2024]
- Parade Of Planets And More Your Skywatching Guide To Astronomical Events This June - TRAVEL + LEISURE INDIA - May 31st, 2024 [May 31st, 2024]
- Free astronomy lecture in Lincoln City | Coast Life | newportnewstimes.com - Newport News Times - May 31st, 2024 [May 31st, 2024]
- Venus likely has active volcanoes, flowing streams of lava - Astronomy Magazine - May 31st, 2024 [May 31st, 2024]
- New photos of the dark universe from Euclid are filled with wonder - Astronomy Magazine - May 31st, 2024 [May 31st, 2024]
- James Webb Space Telescope spots the two most distant galaxies ever seen at cosmic dawn - University of Arizona News - May 31st, 2024 [May 31st, 2024]
- Featured speaker to discuss T Coronae Borealis, solar cycle at Quincy Astronomy Club meeting Thursday Muddy ... - Muddy River News - May 31st, 2024 [May 31st, 2024]
- Audience Mesmerized by 3D Shiur on Rambam's Astronomy - Anash.org - Good News - May 31st, 2024 [May 31st, 2024]
- Astronomers Fear Destructive Light Pollution From FCC's 'Single Network Future' - BroadbandBreakfast.com - May 31st, 2024 [May 31st, 2024]
- Caltech's Shri Kulkarni Awarded Shaw Prize in Astronomy For His Ground-Breaking Discoveries - SciTechDaily - May 31st, 2024 [May 31st, 2024]
- Astronomers Spot Epic Flows of Lava Oozing Out of Venus - Futurism - May 31st, 2024 [May 31st, 2024]
- The summer solstice: What is it and when does it occur? - Space.com - May 31st, 2024 [May 31st, 2024]
- 6 Stars Will Soon Be Visible at the Same Time in Rare 'Parade of Planets' - Yahoo News Canada - May 31st, 2024 [May 31st, 2024]
- Astronomy clubs want to help you enjoy the eclipse safely - NPR - March 16th, 2024 [March 16th, 2024]
- You Can See a Rare, Bright Comet This Month. Will It Be Visible During the Solar Eclipse? - Smithsonian Magazine - March 16th, 2024 [March 16th, 2024]
- Solar Eclipse Path Map Shows States Where Sun Will Be Blocked Out - Newsweek - March 16th, 2024 [March 16th, 2024]
- Deep-space astronomy sensor peers into the heart of an atom - Space.com - March 16th, 2024 [March 16th, 2024]
- Physics and Astronomy Colloquium - Professor Paul Cassak; Department of Physics and Astronomy, West Virginia ... - The University of Iowa - March 16th, 2024 [March 16th, 2024]
- United Nations prioritizes discussion of Dark and Quiet Skies - Astrobites - March 16th, 2024 [March 16th, 2024]
- The burning acid behind ant stings was spotted around two stars - WAPT Jackson - March 16th, 2024 [March 16th, 2024]
- The oddities known as Centaurs may sprout their tales after jumping to new orbits - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- Pair of astronomy brothers to host eclipse viewing event - KAIT - March 16th, 2024 [March 16th, 2024]
- How to watch the solar eclipse online - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- How does a black hole get to the center of a galaxy, and does the galaxy revolve around it? - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- The eclipse gives astronomy clubs an opportunity to shine - Voice Of Alexandria - March 16th, 2024 [March 16th, 2024]
- AI 'for all': How access to new models is advancing academic research, from astronomy to education - Source - Microsoft - March 16th, 2024 [March 16th, 2024]
- KU Department of Physics & Astronomy professor receives prestigious NSF award for black hole research - Salina Post - March 16th, 2024 [March 16th, 2024]
- Inspect impressive Mare Imbrium Astronomy Now - Astronomy Now Online - March 16th, 2024 [March 16th, 2024]
- The Sky This Week from March 15 to 22: A conjunction of Venus and Saturn - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- Pons-Brooks and M31 - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- The slightly weird mathematical coincidence behind an eclipse - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- APOD: 2024 March 17 NGC 7714: Starburst after Galaxy Collision - Astronomy Picture of the Day - March 16th, 2024 [March 16th, 2024]
- How to Safely View the Eclipse National Radio Astronomy Observatory - National Radio Astronomy Observatory - March 16th, 2024 [March 16th, 2024]
- NOIRLab releases jaw-dropping images, video of remnants from massive star explosion | Astronomy.com - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- JWST spots oceans' worth of water evaporating from a distant disk - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- Radiation is vaporizing a young star's disk in the Orion Nebula - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- APOD: 2024 March 12 A Galaxy Shaped Rocket Exhaust Spiral - Astronomy Picture of the Day - March 16th, 2024 [March 16th, 2024]
- Best laptops for astronomers and astrophotographers in 2024 - Space.com - March 16th, 2024 [March 16th, 2024]
- Why astronomers are worried about 2 major telescopes right now - Space.com - March 16th, 2024 [March 16th, 2024]
- The People Behind Webb | Webb - WebbTelescope.org - March 16th, 2024 [March 16th, 2024]
- X-ray image of universe reveals almost 1 million high-energy objects: 'These are mind-blowing numbers' - Space.com - February 1st, 2024 [February 1st, 2024]
- Galaxy named 'Nube' is almost invisible, baffling astronomers Earth.com - Earth.com - February 1st, 2024 [February 1st, 2024]
- Giant Star Seen 150 Days Before it Exploded as a Supernova - Universe Today - February 1st, 2024 [February 1st, 2024]
- UH astronomer named to prominent national astronomical society | University of Hawaii System News - University of Hawaii - February 1st, 2024 [February 1st, 2024]
- The Art of SeeingStates of Astronomy - Announcements - E-Flux - February 1st, 2024 [February 1st, 2024]
- Pluto isn't really a planet, but it might be Arizona's official state planet - Arizona Mirror - February 1st, 2024 [February 1st, 2024]
- Did You Know? Stars Near and Far Reveal Their Secrets to CSUN Scientists - California State University, Northridge - February 1st, 2024 [February 1st, 2024]
- Top 10 space stories of 2023 - Astronomy Magazine - February 1st, 2024 [February 1st, 2024]
- How we found the Milky Way's bar: This Week in Astronomy with Dave Eicher - Astronomy Magazine - February 1st, 2024 [February 1st, 2024]
- The best telescope to use with a smartphone - Astronomy Magazine - February 1st, 2024 [February 1st, 2024]
- JWST releases 19 awe-inspiring images of spiral galaxies - Astronomy Magazine - February 1st, 2024 [February 1st, 2024]
- Learning Shines Brightly at SuperKnova National Radio Astronomy Observatory - National Radio Astronomy Observatory - February 1st, 2024 [February 1st, 2024]
- The Crafoord Prize 2024 goes to three ERC grantees for their pioneering contributions to astronomy and mathematics ... - European Research Council - February 1st, 2024 [February 1st, 2024]
- The Moon's south pole is likely not the safest place for manned missions - Astronomy Magazine - February 1st, 2024 [February 1st, 2024]
- The moon could be perfect for cutting-edge telescopes but not if we don't protect it - Space.com - February 1st, 2024 [February 1st, 2024]
- February Astronomy: Spot the Milky Way and the Zodiacal Light While the Skies Are Darkest - Coachella Valley Independent - February 1st, 2024 [February 1st, 2024]
- You can stream an asteroid whizzing past Earth this weekend - Astronomy Magazine - February 1st, 2024 [February 1st, 2024]