<p>@astrosnapper's <a href="https://astronomy.stackexchange.com/a/29034/7982">answer</a> to the question <em>Could stellar occultations be used to survey Kuiper belt objects?</em> mentions the TAOS-II project and asteroid occultation measurements (which occur on the timescale of seconds) and that got me thinking about the term Time Domain Astronomy.</p>

<p>A quick search led me to an Astrobites post with a catchy title <a href="https://astrobites.org/2012/11/12/a-big-step-backward-for-time-domain-astronomy/" rel="nofollow noreferrer">A Big Step Backward for Time Domain Astronomy</a> that (among other things) describes the DASCH project (Digital Access to a Sky Century @ Harvard).</p>

<p>The post is dated 2012 and says:</p>

<blockquote>
  <p>The project is working to (1) digitally scan all of the plates, (2) detect sources on the plates, (3) assign physical coordinates to the plates, and (4) measure/calibrate the magnitudes of all sources.  The end product will be a publicly available database which can be queried to produce the 100 year light curve for individual objects.  As a part of the project the team had to develop a specialized scanner, as commercially available units would have been too slow to finish the project in anything resembling a reasonable amount of time. As it is, when operating at full efficiency, the project can now scan and analyze 400 plates a day.  As of the writing of this article, 38,346 plates have been scanned (~8% completion; see Figure 2 for a map of their current coverage) and over 2.7 billion magnitudes have already been measured.</p>
</blockquote>

<p>The article ends with:</p>

<blockquote>
  <p>...Given that we’re only 8% of the way through analyzing the plates, <strong>we can look forward to further interesting discoveries from this survey in the next few years.</strong></p>
</blockquote>

<p>It is now six years later. Presumably the scan rate has accelerated a bit and a much larger fraction of the plates have been scanned, and techniques for reducing and analyzing the huge amounts of data have improved as well.</p>

<p>Since 2012, what new discoveries have been made from this effort? There may be too many to list, so a few highlights and a link to a summary might be the best way to answer.</p>

<data-analysis><sky-survey>
What discoveries have come from the DASCH project (Digital Access to a Sky Century @ Harvard)
uhoh
# What discoveries have come from the DASCH project (Digital Access to a Sky Century @ Harvard)

(Asked by: username_0 on 2019-01-05)

@astrosnapper's [answer](https://astronomy.stackexchange.com/a/29034/7982) to the question *Could stellar occultations be used to survey Kuiper belt objects?* mentions the TAOS-II project and asteroid occultation measurements (which occur on the timescale of seconds) and that got me thinking about the term Time Domain Astronomy.

A quick search led me to an Astrobites post with a catchy title [A Big Step Backward for Time Domain Astronomy](https://astrobites.org/2012/11/12/a-big-step-backward-for-time-domain-astronomy/) that (among other things) describes the DASCH project (Digital Access to a Sky Century @ Harvard).

The post is dated 2012 and says:

> The project is working to (1) digitally scan all of the plates, (2) detect sources on the plates, (3) assign physical coordinates to the plates, and (4) measure/calibrate the magnitudes of all sources. The end product will be a publicly available database which can be queried to produce the 100 year light curve for individual objects. As a part of the project the team had to develop a specialized scanner, as commercially available units would have been too slow to finish the project in anything resembling a reasonable amount of time. As it is, when operating at full efficiency, the project can now scan and analyze 400 plates a day. As of the writing of this article, 38,346 plates have been scanned (~8% completion; see Figure 2 for a map of their current coverage) and over 2.7 billion magnitudes have already been measured.

The article ends with:

> ...Given that we’re only 8% of the way through analyzing the plates, **we can look forward to further interesting discoveries from this survey in the next few years.**

It is now six years later. Presumably the scan rate has accelerated a bit and a much larger fraction of the plates have been scanned, and techniques for reducing and analyzing the huge amounts of data have improved as well.

Since 2012, what new discoveries have been made from this effort? There may be too many to list, so a few highlights and a link to a summary might be the best way to answer.

**Tags:** data-analysis, sky-survey


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## 0 answers

