The Astronomer’s Toolkit

Brandon Lawton of the Space Telescope Science Institute
For thousands of years, astronomers have employed increasingly precise angular measures to track the positions of stars in the night sky. The invention of the telescope, just a few hundred years ago, greatly expanded our view beyond what the human eye could see. Technology, in the forms of photography, electronics, digital detectors, and computer analysis, brought revolutions to our capabilities and knowledge. Join us for an exploration of the modern tools and methods used by astronomers with highlights of the recent results they have enabled. In addition, get acquainted with several hands-on tools that you can use to explore authentic NASA data.
Host: Dr. Frank Summers of the Space Telescope Science Institute
Recorded live on Tuesday, September 3, 2019, at the Space Telescope Science Institute in Baltimore, Maryland, U.S.A.
More information: www.stsci.edu/public-lectures

[@carlottasecchi4261]

Thank you so much!

[@storyonbike]

Amazing ..

[@VGAstudent]

@42:41 there is mention of different constants observed by different telescopes using different points of reference, should also realize the different points of time that their vields of view encompases. If you have a view of the stars of the universe seen in a galaxy several billion light years away and compare it with a star group that only includes stars relatively close to our solar system, then the difference of time when those pictures were taken will reflect the physics of the unvierse at that time: If you include stars from the earliest part of the birth of the big bang, compared with stars only seen within the glare of our atmosphere, you will get a vast difference of detail, and by nature of washing out the distant galaxies, wash out the effects of the early part of the universe in your observations. You should have a much higher rate of expansion the further out you look to correspond to how far back you see into the unverse's past. Five billion light years away also means five billion light years into the past. If one group of observations is incapable of getting that kind of distance, then you will have a much more shallow expansion value because it does not have enough of the earliest relative movements to us that the earliest galaxies had. The most important detail is the similarity of time, that means the same relative distance from us, the observer, with that kind of filter on the astronomical historical record, that is the visible and invisible sky, we have a much more detailed and accurate map of the earliest times in our observable universe's existence since the big bang. That is the part of astronomy I'd like to see studied, it should prove any trend in the gravitational constant of the universe at different times of expansion. To make a true map of the unvierse, it would have to include the adjustment of light we capture as a moving solar-system to get the static movement calculated for a "real" redshift or blueshift assessment of the unverse. There may be no real "Great Attractor", just the relative motion of our solarsystem through the milky way skewing our observations of the stars in one direction or another throughout history, with only the details revealed in recent history. It takes approximately 250 million years for the solarsystem to orbit the milkyway galaxy, and we've observed stars movements in relation to us, but we have no idea how fast or in what direction the milky way galaxy is going except in relation to our own local group of galaxies, otherwise, there's a huge void before we see the next group of galaxies. We may be an ejected small galactic group called the "local group" meeting yet another small ejected galactic group, and that may be the norm, but we're too short in the lifespan of the unvierse to track all those nuances with anything except imagination and theory. To start a truly galactic survey of the milky way galaxy, we'd have to place a station parked in space that was stationary in relation to Sagitarius A*, the black hole at the center of our galaxy. We would have to have a relatively absolutely stable position for us to call the "center" of the universe to make any kind of accurate guess or estamate, but all estamates are based upon assumptions that need to be verified in the face of the facts. It would be a good assumption to make that the universe was expanding faster at the beginning, towards the big bang, than it is now, towards what would be considered "contemporary", and what we see locally is that we are merging. Andromeda is on a direct course for us and we for it. Nothing messy can occur with stars colliding, space is still too vast between even tightly clustered stars to make that too much of an occurrance, but there will be orbits thrown into a new center of mass between the two galaxies, stars will be tossed out into the vastness of space to fade into nothingness by themselves, no longer as a part of the merged galaxies, and may be a true indicator of where all the dark matter really came from. How many stars get ejected from two merging galaxies the size of Andromeda, and if that was an average, how many galaxies had to merge across the unverse to create that kind of lost "ejected star stuff" gone dark, dark matter density that we observe in our galaxy or other galaxies across the universe?

[@user-gd5yt2gn6r]

Thank You.

[@willemvandebeek]

reupload?

[@TwinLeaf123]

gdelb?

[@HisBortness]

I love this series, but I must acknowledge that Frank's intros always sound so condescending. He sounds like he thinks he needs to talk down to people so they can understand him, like his normal way of speaking would just be too much for the common person to understand.