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A bunch of extremely distant quasars has recently been discovered using a new technique. A quasar is a very luminous extragalactic object with a supermassive black hole that interacts with a disk of gas surrounding it, and quasars at the distances mentioned in the discovery are very important in understanding a period in the universe's history when things essentially started "calming down" after the big bang.
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Astronomers discover 16 new high-redshift quasars"
https://phys.org/news/2017-03-astronomer...asars.html
Much of the data used in this study came from UKIRT on Mauna Kea. Incidentally, UKIRT still holds the record for the most distant quasar ever detected at a redshift of 7.1 (about 13 billion light years away).
http://www.space.com/28499-finding-the-m...uasar.html
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Thanks Tom, always good to read about the great work being done up there.
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This is something much closer to my own area of research than many of the other discoveries mentioned here.
Polycyclic aromatic hydrocarbons (PAHs) are molecules that your gasolene-powered car and barbecue create. They are also observed in various regions in space, basically, anywhere you have a supply of hydrogen and carbon will create them and they are a very important part of creating more complex molecules required for life. Because they tend to show up at mainly mid-infrared wavelengths, they are are difficult to observe from the ground which is why, so far, observations of the molecules have been limited to nearby objects in our Galaxy and others nearby. This study, using infrared observations from space (Spizer and Herschel) and the Keck on Mauna Kea, have now observed PAHs in distant galaxies which existed when the universe was young.
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Tracing aromatic molecules in the early universe"
https://phys.org/news/2017-03-aromatic-m...verse.html
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Detecting life in the Milky Way
This is an article some here might be interested in reading. It discusses the instrumentation currently being planned for the TMT to help explore exoplanets and look for signs of life. The Kecks on Mauna Kea will be used to test the instrumentation.
https://phys.org/news/2017-03-tools-life.html (*)
(*) There is an error in the article. It claims the TMT will be the largest optical telescope in the world. That's untrue. The E-ELT in Chile will be larger.
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Apologies for not posting in this thread recently, but the discoveries are continuing. Just briefly, here are the latest from MK:
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New extended ionized gas clouds detected in Abell 1367 cluster"
Probably not too exciting for the layperson, but these clouds indicate how gas is lost by early galaxies, which influences star and planet formation, so helps us understand how early galaxies evolve.
https://phys.org/news/2017-04-ionized-ga...uster.html
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The monster galaxy that died too quickly "
A surprise for astronomers - a distant galaxy that "died" much earlier than expected.
https://phys.org/news/2017-04-monster-ga...ickly.html
http://www.keckobservatory.org/recent/en...ead_galaxy
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Primordial Galaxy Discovered, First of Its Kind"
The surprise here is that the galaxy appears to be ordinary, whereas galaxies seen at that distance (13.1 billion light years - the universe is 13.8 billion years old). The only way it was found was through gravitational lensing, which can focus light and make something faint look much brighter.
http://www.keckobservatory.org/recent/en...f_its_kind
https://phys.org/news/2017-04-average-ga...epoch.html
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Astronomers discover new substellar companion using microlensing"
Another way to use gravitational lensing, in this case microlensing, in which a small planet orbiting a star temporarily brightens the star from our perspective.
https://phys.org/news/2017-04-astronomer...nsing.html
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Good morning Tom, I really enjoy this thread, thanks.
Have any telescopes on Mauna Kea been involved in discovering water elsewhere in our solar system? NASA is having a press conference tomorrow morning regarding discoveries by Hubble and Cassini of "alien oceans in Earth's solar system". Of course we've known about that possibility on Europa for a while now.
http://www.space.com/36421-nasa-revealin...il-13.html
Folks, please refrain from water on Uranus jokes.
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SBH - I assume you're thinking more of liquid water rather than water in its other phases, i.e., steam or ice. In that case, it's very difficult for ground-based telescopes to detect liquid water, even on Mauna Kea, because there is so much of it in the atmosphere. The wavelengths you would use to detect water are essentially blocked by the atmosphere which is why that particular line of investigation is much better done from space.
On the other hand, the MK observatories have been involved in several detections of water in its other forms, especially ice. They have been used to detect water ice on comets and asteroids in our solar system, including to some extent Mars and other solar system minor objects. They have also been extensively used to study water ice elsewhere in the Milky Way, especially in molecular clouds and star forming regions. I spent a lot of my time as a young astronomer doing exactly those types of observations, often using spectroscopic observations of water and CO ices to attempt to identify other molecules that were hard or impossible to detect from Earth (e.g., carbon dioxide and molecular oxygen and nitrogen).
So, yes, they are used to detect water, but no so much liquid water.
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More from Mauna Kea:
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Waterloo researchers capture first “image” of a dark matter web that connects galaxies"
This is the first time that "dark matter", which makes up most of the mass in the universe but cannot yet be detected directly, is shown to connect galaxies in the "cosmic web". The data were collected at the Canada France Hawaii Telescope on Mauna Kea (CFHT).
http://www.ras.org.uk/news-and-press/297...s-galaxies
https://phys.org/news/2017-04-capture-im...axies.html
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Astronomers piece together first image of black hole"
Although we know black holes exist, by their very nature you can't see them as light is unable to escape once it's inside what's known as the "Schwarzschild radius" or the event horizon. This is an attempt to image a black hole by comparing the area in which you see nothing to the region around it, which is very bright due to the emission from all the hot material falling into the black hole. A bit like looking straight down a plug hole as the water drains around it.
To achieve the resolution required, telescopes from around the world were used to synthesize a telescope with roughly the same diameter as the Earth. This included the JCMT on Mauna Kea.
The results should be available in a few months.
https://phys.org/news/2017-04-astronomer...-hole.html
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Great stuff, thanks for keeping us informed.
"To achieve the resolution required, telescopes from around the world were used to synthesize a telescope with roughly the same diameter as the Earth."
Amazing!
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Yes thank you TomK for keeping us informed. Double star system, really? Wow!
Seen some intriguing astronomy stuff on the Science Chnl...NASA Unexplained is one of them. Saw a great docu on Mission Pluto and the unknown factors they faced when they launched the space craft. How better technology came along after the launch. It gave a bio of Clyde which included the info of his ashes flying through space.
Can't get over how cool that is...
