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This is a very interesting video about 'Oumuamua, our so-called first interstellar visitor in the Solar System, and a warning about jumping to conclusions:
https://youtu.be/hkZRUs8A_9Q
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It's a big one, but it'll miss:
The biggest asteroid to visit Earth this year is zooming by our planet today (March 21) and it's a real speed demon.
The asteroid 2001 FO32 is hurtling through space at an unusually fast speed for a space rock, about 77,000 mph (124,0000 kph), and will pass by Earth at a safe range of 1.25 million miles (2 million kilometers), according to NASA.
Astronomers have been using NASA's Infrared Telescope Facility atop Mauna Kea in Hawaii in recent days to determine its chemical composition.
https://www.space.com/biggest-asteroid-f...fast-speed
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An updated, clearer black hole photo from the 2019 Event Horizon project has been released. It's a beautifully detailed image revealing a magnetic field swirl. Some background and comments on the new rendering:
In 2019, the Event Horizon Telescope project — a network of eight radio telescopes around the world that includes the James Clerk Maxwell Telescope and the Submillimeter Array on Maunakea — made history by capturing the first image of a black hole.
The same project today released a second picture of the same black hole with more visible detail.
... the new image reveals a swirl pattern that shows for the first time the structure of the intense magnetic field distortions around the black hole, said Jessica Dempsey, deputy director of the East Asian Observatory and JCMT.
“It’s exciting for use to really get to drill down into what these magnetic fields are doing.”
https://www.hawaiitribune-herald.com/202...le-detail/
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04-26-2021, 05:44 PM
(This post was last modified: 04-26-2021, 06:31 PM by HereOnThePrimalEdge.)
This week the 2021 IAA Planetary Defense Conference takes places virtually from Vienna. Telescopes on Mauna Kea and Haleakala are part of the international system of observatories which track potentially dangerous asteroids headed toward Earth.
https://iaaspace.org/event/7th-iaa-plane...ence-2021/
Part of the meeting includes:
The 2021 PDC Hypothetical Asteroid Impact Scenario
Although this scenario is realistic in many ways, it is completely fictional and does NOT describe an actual potential asteroid impact.
(Hypothetical) Asteroid 2021 PDC will remain continuously observable over the entire time from now until the potential impact in October, although it will be fainter than 23rd magnitude from June through September, requiring large-aperture telescopes such as the 4-meter Canada-France-Hawaii Telescope (CFHT). The asteroid will not get brighter than 22nd magnitude until just a few weeks before the potential impact in October.
https://cneos.jpl.nasa.gov/pd/cs/pdc21/
At the link, scroll down to the image which shows potential impact areas on Earth. Due to so many variables there are hundreds of red dots scattered across the globe. With a larger telescope such as the TMT the asteroid might be discovered sooner, it's orbit calculated weeks or months earlier, likely impact areas better identified, and more effective mitigation plans set into motion sooner.
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Sorry for pouring cold water over this, but the TMT isn't going to be the telescope that detects an earth-killing asteroid. The smaller aperture telescopes, such as CFHT, UKIRT, and Pan-STARRS are the observatories that are more likely to detect those sorts of asteroids. The TMT will have no wide-field capability so although it can detect fainter objects, it has such a small field of view it's extremely unlikely it will ever detect a faint asteroid heading towards Earth. It will come in handy after such a detection by other telescopes. The 4-meter class telescopes, on the other hand, have wide-field capabilities meaning they can check large parts of the sky quickly and detect moving objects.
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04-27-2021, 07:44 PM
(This post was last modified: 04-28-2021, 04:24 AM by HereOnThePrimalEdge.)
The smaller aperture telescopes, such as CFHT, UKIRT, and Pan-STARRS are the observatories that are more likely to detect those sorts of asteroids.
TomK,
Yes, with a wide field capability, taking in more of the sky would provide a better opportunity for spotting an asteroid. Perhaps you can clarify what I understood (misunderstood?) about how the Planetary Defense system operates:
Pan-STARRS on Haleakala, as well as a network of other observatories are dedicated or have dedicated times with which they watch for unusual moving objects against the background of stars. If an object is spotted, the position might then be provided to a larger telescope, one with a relatively wide field, such as the CFHT mentioned in the link I posted. I assumed if the object's path could intersect with earth's orbit, larger observatories might then make observations (knowing it's exact location) and would better determine the object's size, speed, rotation, shape, etc so a more accurate path could be calculated, and we would know sooner if it is on a direct course for earth, and if irregularities in shape or rotation might cause it to bounce off our atmosphere, break apart, or change direction if it did enter our atmosphere. The potential impact map https://cneos.jpl.nasa.gov/pd/cs/pdc21/ has red dots all across the globe. Wouldn’t observations from a larger telescope reduce the number of possible target areas?
I don't know the procedure for information sharing among observatories so if you have a moment would it be possible to clarify and explain?
Thanks.
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HOTPE - no problem. For us (UKIRT), we have no procedure to follow and am not sure what other telescopes would do, but my guess is the procedure would be the following:
1) A telescope that discovers a new asteroid will report it via the IAU (International Astronomical Union) and via any other available sources, but essentially there is a network set up to make everyone aware of transient or new events;
2) Followups will be done by observatories, and in the case of an asteroid, several observations taken over a period of a few days will provide a reasonable orbit for the object;
3) At that point, it will be obvious if it threatens Earth. It's not really something that has happened recently, but at that point the larger observatories would likely be used to observe the object and try and determine what it is and what it is made of.
Basically, the role of large observatories in this case, such as the TMT, would be to observe the object in as much detail as possible while it is still distant so we have time to determine what we can do to mitigate the threat. They would also be helpful in refining the orbit and making predictions more accurate.
Essentially, it' the smaller telescopes that have wide-field capabilities that would discover the object and after that, the larger ones determine what the object is and what it is made of.
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Hawaii is on the front lines in the search for asteroids which could intersect earth’s orbit. This year, Asteroid Day will be preceded by a month long intro with Asteroid Day TV:
The Asteroid Foundation will launch Asteroid Day TV on 1 June 2021 with digital video content from Discovery Science, TED, IMAX, BBC, CNN, The Planetary Society, the European Space Agency (ESA), independent filmmakers and other educational content producers. The programming will cover themes such as asteroid discovery, planetary defense, space resources, asteroid exploration missions and more. Asteroid Day is an official United Nations’ day of global awareness about the opportunities and challenges that asteroids present. Asteroid Day was co-founded by astrophysicist and famed musician Dr Brian May of the rock group Queen; Apollo 9 Astronaut Rusty Schweickart; Filmmaker Grig Richters; and B612 Foundation President Danica Remy to educate the public about the importance of asteroids in our history, the role they play in the solar system and how they could affect our future.
https://asteroidday.org
Some background on the contribution of Hawaii’s observatories in tracking asteroids:
https://www.channel3000.com/on-internati...-to-earth/
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If we build the TMT, this is what’s next:
But the weirdest of these worlds sit far from the sun in the Kuiper Belt and share basic properties with Pluto. At the moment, these so-called Plutoids are mostly known from grainy images and via Earth-based detections of chemicals found on their surfaces.
That could soon change, thanks to the next generation of large telescopes under construction in places like Chile and Hawaii. These instruments should reveal surface details better than even the Hubble Space Telescope can provide.
https://www.discovermagazine.com/the-sci...d-as-pluto
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When did the first stars in the universe shine?
The Universe came into being 13.8 billion years ago in the Big Bang. After an initial flash, it went through a period known as the cosmic dark ages. According to the new study, 250 to 350 million years after the Big Bang, the first stars emerged, bringing light to the cosmos.
The team needed 70 hours of observing time, using four of the largest ground-based telescopes to estimate their distances. These were the Atacama Large Millimetre Array (Alma), the Very Large Telescope (VLT) and the Gemini South Telescope - all located in Chile - as well as the twin Keck telescopes in Hawaii.
https://www.bbc.co.uk/news/science-environment-57515422
When the James Webb Space Telescope launches later this year, it may see that first light.
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