Posted on 06/03/2018 9:18:47 AM PDT by LibWhacker
This article was originally published at The Conversation. The publication contributed the article to Space.com's Expert Voices: Op-Ed & Insights.
Earlier this year, astronomers stumbled upon a fascinating finding: Thousands of black holes likely exist near the center of our galaxy.
The X-ray images that enabled this discovery weren't from some state-of-the-art new telescope. Nor were they even recently taken – some of the data was collected nearly 20 years ago.
No, the researchers discovered the black holes by digging through old, long-archived data.
Discoveries like this will only become more common, as the era of "big data" changes how science is done. Astronomers are gathering an exponentially greater amount of data every day – so much that it will take years to uncover all the hidden signals buried in the archives.
Sixty years ago, the typical astronomer worked largely alone or in a small team. They likely had access to a respectably large ground-based optical telescope at their home institution.
Their observations were largely confined to optical wavelengths – more or less what the eye can see. That meant they missed signals from a host of astrophysical sources, which can emit non-visible radiation from very low-frequency radio all the way up to high-energy gamma rays. For the most part, if you wanted to do astronomy, you had to be an academic or eccentric rich person with access to a good telescope.
Old data was stored in the form of photographic plates or published catalogs. But accessing archives from other observatories could be difficult – and it was virtually impossible for amateur astronomers.
Today, there are observatories that cover the entire electromagnetic spectrum. No longer operated by single institutions, these state-of-the-art observatories are usually launched by space agencies and are often joint efforts involving many countries.
With the coming of the digital age, almost all data are publicly available shortly after they are obtained. This makes astronomy very democratic – anyone who wants to can reanalyze almost any data set that makes the news. (You too can look at the Chandra data that led to the discovery of thousands of black holes!)
These observatories generate a staggering amount of data. For example, the Hubble Space Telescope, operating since 1990, has made over 1.3 million observations and transmits around 20 GB of raw data every week, which is impressive for a telescope first designed in the 1970s. The Atacama Large Millimeter Array in Chile now anticipates adding 2 TB of data to its archives every day.
The archives of astronomical data are already impressively large. But things are about to explode.
Each generation of observatories are usually at least 10 times more sensitive than the previous, either because of improved technology or because the mission is simply larger. Depending on how long a new mission runs, it can detect hundreds of times more astronomical sources than previous missions at that wavelength.
For example, compare the early EGRET gamma ray observatory, which flew in the 1990s, to NASA's flagship mission Fermi, which turns 10 this year. EGRET detected only about 190 gamma ray sources in the sky. Fermi has seen over 5,000.
The Large Synoptic Survey Telescope, an optical telescope currently under construction in Chile, will image the entire sky every few nights. It will be so sensitive that it will generate 10 million alerts per night on new or transient sources, leading to a catalog of over 15 petabytes after 10 years.
The Square Kilometre Array, when completed in 2020, will be the most sensitive telescope in the world, capable of detecting airport radar stations of alien civilizations up to 50 light-years away. In just one year of activity, it will generate more data than the entire internet.
These ambitious projects will test scientists' ability to handle data. Images will need to be automatically processed – meaning that the data will need to be reduced down to a manageable size or transformed into a finished product. The new observatories are pushing the envelope of computational power, requiring facilities capable of processing hundreds of terabytes per day.
The resulting archives – all publicly searchable – will contain 1 million times more information that what can be stored on your typical 1 TB backup disk.
The data deluge will make astronomy become a more collaborative and open science than ever before. Thanks to internet archives, robust learning communities and new outreach initiatives, citizens can now participate in science. For example, with the computer program Einstein@Home, anyone can use their computer's idle time to help search for rapidly-rotating neutron stars.
It's an exciting time for scientists, too. Astronomers like myself often study physical phenomena on timescales so wildly beyond the typical human lifetime that watching them in real-time just isn't going to happen. Events like a typical galaxy merger – which is exactly what it sounds like – can take hundreds of millions of years. All we can capture is a snapshot, like a single still frame from a video of a car accident.
However, there are some phenomena that occur on shorter timescales, taking just a few decades, years or even seconds. That's how scientists discovered those thousands of black holes in the new study. It's also how they recently realized that the X-ray emission from the center of a nearby dwarf galaxy has been fading since first detected in the 1990s. These new discoveries suggest that more will be found in archival data spanning decades.
In my own work, I use Hubble archives to make movies of "jets," high-speed plasma ejected in beams from black holes. I used over 400 raw images spanning 13 years to make a movie of the jet in nearby galaxy M87. That movie showed, for the first time, the twisting motions of the plasma, suggesting that the jet has a helical structure.
This kind of work was only possible because other observers, for other purposes, just happened to capture images of the source I was interested in, back when I was in kindergarten. As astronomical images become larger, higher resolution and ever more sensitive, this kind of research will become the norm.
This article has been updated to correct what Einstein@Home searches for.
Data Firehose?
More like Data Niagara Falls!
Slowly I turn...
Since the light or em radiation from objects we now access is supposedly what happened many many years ago...could it be possible that those objects no longer exist at this very moment?
If true, Thomas More has probably posted a picture of it from the NASA archives. He was/is? very much on top of such things.
Where did he go as those are no longer found?
Astronomy Picture of the Day Archive
https://apod.nasa.gov/apod/archivepix.html
There is so much out there to discover. AWESOME!
Absolutely. And how is it possible that we are viewing events that happened billions of years ago at at the beginning of the universe yet it is impossible for matter to travel fast enough to be that far away in lightyears according to special relativity?
Not only possible, but quite likely in many cases. What we see as dying stars that are 150 million miles away are almost surely fully dead by now.
A review a the beginning of the universe should be your first step.
Magic?
Yes. Today if we see a supernova 12 billion light years away, it surely is no longer either a star or a supernova. The nebula has dissipated and the core has probably become a neutron star after passing through its pulsar phase. Yes, I would even go so far as to say that not many large scale objects we see far out (billions of light years) in space are still what they appear to be, red dwarfs, galaxies and supermassive black holes excepted, even if we hypothetically could see everything that’s out there that far out.
I see you have not taken the first step.
Lemme guess. Space-time and matter as we know it didn’t exist so SR didn’t apply. Like a massive space-time warp.
When I initially saw the Hubble images of Eagle Nebula, (Pillars of Creation) years ago, I was flat out blow away, not only by the image, but the size of it. So much so, I had to see it for myself.
I shot the above image a few years back, not Hubble quality, but I didn't have Hubble's budget either.☺
However, it was a supernova explosion which blew them apart. But as you know, their image will linger for another thousand years as it takes that long for light to travel from there to Earth.
The size? The pillar on the left is about 23,462,784,000,000 miles in length, that's **23 trillion** miles tall.
And the whole thing was blow away!☺
If you want on or off the Electric Universe Ping List, Freepmail me.
Of course. It’s also possible the universe has already collapsed and we’re seeing only what used to be. There is nothing to prevent our obliteration; that it hasn’t happened yet is so far, so good, but no guarantee it won’t happen before you finish reading this.
Absolutely. And how is it possible that we are viewing events that happened billions of years ago at at the beginning of the universe yet it is impossible for matter to travel fast enough to be that far away in lightyears according to special relativity?
So that would mean that as the nothing something boundary is still propagating outward like an expanding balloon.
No boundary. Think of it as the surface of a basketball the is being inflated. Based on what we’ve observed, the universe is likely finite, not infinite, but unbounded. What does that mean? It is measurable, but there is no edge.
Aliens and their spaceship being kept at Area 51 in Nevada.
Thanks Swordmaker. Additional ping to APoD list.
Celinedeion.............
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.