Recent comments in /f/space

oicura_geologist t1_jefqqm4 wrote

Reply to comment by bluesam3 in The brightest gamma-ray in human history hit our planet this past Fall by PuzzleheadedOne1428

Geology is a historic science. Perspective, to a geologist; pre-history is anything that happens prior to creation of the planet 4500 Ma. To a Cosmologist, pre-history is prior to the inflationary period 1x10^-32 sec post big bang. The article itself quotes "Scientists say the gamma-ray burst (GRB), the most powerful type of explosion in the universe, was 70 times brighter than any previously recorded event. So the title of THIS reddit forum claims "The brightest gamma-ray in human history hit our planet this past Fall" is not precise enough. Especially if one considers that Gamma radiation was not detected until 1903 by humans, and thus, the title is patently wrong considering the perspective of the historical argument.

Your opinion that "History" is only what is written, is a fallacy as many sciences see "history" in very different ways.

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LimerickJim t1_jefo49z wrote

Reply to comment by brokejetflyer in Path forward begins to emerge for Thirty Meter Telescope, which would be larger than any other current optical telescope and would sit atop the dormant volcano Mauna Kea in Hawaii. by clayt6

This article actually doesn't provide enough technical information to answer this. I would need to know the operational frequency and the specifics of the telescope lens set up to answer.

The term you want to think about for what this telescope can see is resolution. How small an object can the telescope see through it. This is given in terms of solid angle. The closer an object is (over the minimum resolution distance) the smaller the telescope can resolve. An object in orbit can be size x, an object on the moon has to be larger than x, near mars larger still.

An added complication is brightness and interference. The atmosphere scatters a lot of light coming in so if an object isn't reflecting (or emitting) sufficient light the light that it does reflect will be scattered before it reaches the telescope.

This is further complicated by the sensing frequency. The magnification provided by a telescope is directly related to the wavelength of light that it is built to observe. The simplest designs look in the visible spectrum and your eye is the sensor but there are things you can only see at IR or UV wavelengths. There are stars a 30 m IR scope will see that a 30 m visual spectrum telescope can't.

There are other complications like weather, solar conditions, the lunar calendar etc., that also effect but we tend to focus on "ideal conditions".

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LimerickJim t1_jefkx3t wrote

Reply to Path forward begins to emerge for Thirty Meter Telescope, which would be larger than any other current optical telescope and would sit atop the dormant volcano Mauna Kea in Hawaii. by clayt6

This article is about an agreement with the indigenous population to remove several existing telescope sites (these telescopes aren't really needed any more) to place this one. Astronomers at the University of Hawaii had been dicks about the cultural importance of the site until the beginning of these talks during Covid.

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ianindy t1_jefheoz wrote

Reply to comment by [deleted] in Extremely flat explosion dubbed 'the Cow' puzzles scientists while they work to learn more by thawingSumTendies

Here is the description from Wikipedia:

>First described in 1950 by the Dutch astronomer Jan Oort, is a theoretical concept of a cloud of predominantly icy planetesimals proposed to surround the Sun at distances ranging from 2,000 to 200,000 AU (0.03 to 3.2 light-years).

https://en.wikipedia.org/wiki/Oort_cloud

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KarmaWSYD t1_jefghvk wrote

Reply to comment by mouse_puppy in Nokia to set up first 4G network on moon with NASA by Free_Swimming

Yeah, the atmosphere is definitely a factor in range but buildings and the like also serve to stop signals. I'd expect that to be a particular effect when any buildings likely need more shielding from radiation due to, well, being on the moon. Of course, there's a chance that they don't actually need that network capability inside buildings but if they do 4G would most likely be the better option.

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VeryFarDown t1_jefeaat wrote

Reply to comment by [deleted] in Extremely flat explosion dubbed 'the Cow' puzzles scientists while they work to learn more by thawingSumTendies

Actually, the person you replied to is correct. The Oort Cloud is still a hypothesis. This is from Universe Today:

>For thousands of years, astronomers have watched comets travel close to Earth and light up the night sky. In time, these observations led to a number of paradoxes. For instance, where were these comets all coming from? And if their surface material vaporizes as they approach the Sun (thus forming their famous halos), they must formed farther away, where they would have existed there for most of their lifespans.
>
>In time, these observations led to the theory that far beyond the Sun and planets, there exists a large cloud of icy material and rock where most of these comets come from. This existence of this cloud, which is known as the Oort Cloud (after its principal theoretical founder), remains unproven. But from the many short and long-period comets that are believed to have come from there, astronomers have learned a great deal about it structure and composition.

Voyager 1 will reach it in about 300 years, but unfortunately, it won't have the ability/power to report its findings back to us.

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