<p>I'm not an observational expert, but here's what I found. </p>

<p>I found this object (V838 Monocerotis) on the HST data archive. </p>

<p><a href="https://archive.stsci.edu/hst/search.php" rel="noreferrer">https://archive.stsci.edu/hst/search.php</a></p>

<p>I input the 'Target Name' as "<strong>V838 Monocerotis</strong>", clicked all 'Imagers', 'Spectrographs', and 'Other,' and searched it.</p>

<p>(You can also do the exactly the same thing I did because this site is opened for everyone.)</p>

<p>And there are 199 images of this object. And the last observation was made in 2012. Unfortunately, I couldn't see any echoes in the picture taken in 2012. So I looked from the beginning. And I found this!</p>

<p><a href="https://i.sstatic.net/lrFVj.jpg" rel="noreferrer"><img src="https://i.sstatic.net/lrFVj.jpg" alt="J9SF01020"></a></p>

<p>This picture was taken from 2006-09-09 20:04:57 to 2006-09-10 01:14:57. Dataset number is J9SF01020. You can see that the shape of the echo. There are other pictures in the archive, but I couldn't see significant echo shape anymore after that.</p>

<p><strong>I'm sorry to say that the party is over, the echo was faded away.</strong></p>

<p>I also love this picture, it means a lot to me because this picture made me study Astronomy. Thanks for making me remind this memory.</p>

<p>P.S.: If you want other pictures, especially color pictures, check out this link too.</p>

<p><a href="http://hla.stsci.edu/hlaview.html#Images|filterText%3D%24filterTypes%3D|query_string=V838%20Monocerotis&amp;posfilename=&amp;poslocalname=&amp;posfilecount=&amp;listdelimiter=whitespace&amp;listformat=degrees&amp;RA=106.020093&amp;Dec=-3.847399&amp;Radius=0.200000&amp;inst-control=all&amp;inst=ACS&amp;inst=ACSGrism&amp;inst=WFC3&amp;inst=WFPC2&amp;inst=NICMOS&amp;inst=NICGRISM&amp;inst=COS&amp;inst=WFPC2-PC&amp;inst=STIS&amp;inst=FOS&amp;inst=GHRS&amp;imagetype=best&amp;prop_id=&amp;spectral_elt=&amp;proprietary=both&amp;preview=1&amp;output_size=256&amp;cutout_size=12.8|ra=&amp;dec=&amp;sr=&amp;level=&amp;image=&amp;inst=ACS%2CACSGrism%2CWFC3%2CWFPC2%2CNICMOS%2CNICGRISM%2CCOS%2CWFPC2-PC%2CSTIS%2CFOS%2CGHRS&amp;ds=" rel="noreferrer">http://hla.stsci.edu/hlaview.html#Images|filterText%3D%24filterTypes%3D|query_string=V838%20Monocerotis&amp;posfilename=&amp;poslocalname=&amp;posfilecount=&amp;listdelimiter=whitespace&amp;listformat=degrees&amp;RA=106.020093&amp;Dec=-3.847399&amp;Radius=0.200000&amp;inst-control=all&amp;inst=ACS&amp;inst=ACSGrism&amp;inst=WFC3&amp;inst=WFPC2&amp;inst=NICMOS&amp;inst=NICGRISM&amp;inst=COS&amp;inst=WFPC2-PC&amp;inst=STIS&amp;inst=FOS&amp;inst=GHRS&amp;imagetype=best&amp;prop_id=&amp;spectral_elt=&amp;proprietary=both&amp;preview=1&amp;output_size=256&amp;cutout_size=12.8|ra=&amp;dec=&amp;sr=&amp;level=&amp;image=&amp;inst=ACS%2CACSGrism%2CWFC3%2CWFPC2%2CNICMOS%2CNICGRISM%2CCOS%2CWFPC2-PC%2CSTIS%2CFOS%2CGHRS&amp;ds=</a></p>

CC BY-SA 4.0
2018-11-07T03:53:12.460Z
Yes it's a really special event. I first learned about it in this [New York Times video](http://www.nytimes.com/video/science/100000003087764/echoes-of-light.html) and then asked [V838 Monocerotis “light-echo” images morphed into nice video, but why so few original images?](https://astronomy.stackexchange.com/q/14660/7982) The story that the narrator Dennis Overbye tells is quite interesting.
uhoh
CC BY-SA 4.0
2018-11-07T03:55:14.053Z
@uhoh My mistake, I clicked all 'Imagers', 'Spectrographs', and 'Other.'
Study Astrophysics
CC BY-SA 4.0
2018-11-07T03:56:12.797Z
@uhoh Also, this dataset is not sorted by time. I don't know why. By clicking 'Start Time' tap, you can get the list sorted by time.
Study Astrophysics
CC BY-SA 4.0
2018-11-07T03:57:12.590Z
Bingo, thank you, my mistake. I should't have assumed any particular sorting.
uhoh
CC BY-SA 4.0
2018-11-07T03:36:41.383Z
2018-11-07T03:57:44.913Z
2018-11-07T03:57:44.913Z
Study Astrophysics
<p>This <a href="https://astronomy.stackexchange.com/a/14780/7982">answer</a> to the question <a href="https://astronomy.stackexchange.com/q/14660/7982">V838 Monocerotis “light-echo” images morphed into nice video, but why so few original images?</a> contains the following information below. There are other answers and more images there, so it's recommended to enjoy there as well.</p>

<p><strong>Question:</strong> What does V838 Monocerotis look like today? Have there been subsequent light echo image sequences, or is the party over?</p>

<p>See also <a href="https://astronomy.stackexchange.com/q/14781/7982">Why weren't the Hubble light-echo images of V838 Monocerotis supplemented by ground telescopes?</a></p>

<hr>

<hr>

<p>The V838 Monocerotis <em>expansion</em> (not a supernova) and the observation of the subsequent "spectacular" light echo was quite a notable event! From <a href="http://www.nature.com/nature/journal/v422/n6930/abs/nature01508.html" rel="nofollow noreferrer">Nature <strong>422</strong>, 405-408 (27 March 2003)</a></p>

<p><a href="https://i.sstatic.net/xU4aE.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/xU4aE.png" alt="Nature Cover"></a><a href="https://i.sstatic.net/TSrZZ.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/TSrZZ.png" alt="enter image description here"></a></p>

<p>From <a href="http://iopscience.iop.org/article/10.1088/0004-6256/135/2/605" rel="nofollow noreferrer">Astronom. J. <strong>135</strong>, 2, 2008</a> or <a href="http://arxiv.org/abs/0711.1495" rel="nofollow noreferrer">ArXiv</a></p>

<blockquote>
  <p>"<em>.<strong>Galactic light echoes are extremely rare. The only other known example of extent similar to that of V838 Mon was the echo produced by Nova GK Persei 1901</strong> (Kapteyn 1902; Perrine 1902; Ritchey 1902). Following early misunderstandings, light-echo geometry was properly described by Couderc (1939), and more recent discussions are given by many authors, including Chevalier (1986), Felten (1991), Sparks (1994), Sugerman (2003), and references therein</em>".</p>
</blockquote>

<p>It was the sole topic of an international conference <a href="http://www.ing.iac.es/conferences/v838mon/" rel="nofollow noreferrer">photo from here</a>:</p>

<p><a href="https://i.sstatic.net/BgHSZ.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/BgHSZ.jpg" alt="Conference"></a>
<a href="http://www.nature.com/nature/journal/v422/n6930/fig_tab/nature01508_F2.html#figure-title" rel="nofollow noreferrer">Figure 2</a> of the Nature paper describes the preservation of the actual light curve (history) within the structure of the light-echo shell:</p>

<p><a href="https://i.sstatic.net/YztnU.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/YztnU.jpg" alt="enter image description here"></a></p>

<blockquote>
  <p>"<strong>FIGURE 2. HST images of the light echoes</strong>
  The apparently superluminal expansion of the echoes as light from the outburst propagates outward into surrounding dust is shown dramatically. Images were taken in 2002 on 30 April (a), 20 May (b), 2 September (c) and 28 October (d). Each frame is 83" times 83"; north is up and east to the left. Imaging on 30 April was obtained only in the B filter, but B, V and I were used on the other three dates, allowing us to make full-colour renditions. The time evolution of the stellar outburst (Fig. 1) is reflected by structures visible in these colour images. In b, for example, note the series of rings and filamentary structures, especially in the upper right quadrant. <strong>Close examination shows that each set of rings has a sharp, blue outer edge, a dip in intensity nearer the star, and then a rebrightening to a redder plateau. Similar replicas of the outburst light curve are seen propagating outwards throughout all of the colour images</strong>."</p>
</blockquote>

<p><strong>also see:</strong> This is an artificially constructed animation, morphing eight existing images to suggest what a higher cadence imaging campaign might have seen: <a href="https://www.spacetelescope.org/videos/heic0617a/" rel="nofollow noreferrer">https://www.spacetelescope.org/videos/heic0617a/</a></p>

<light><hubble-telescope><dust><v838-monocerotis>
How does V838 Monocerotis look today? Any subsequent light echo images, or is the party over?
uhoh
# How does V838 Monocerotis look today? Any subsequent light echo images, or is the party over?

(Asked by: username_0 on 2018-11-02)

This [answer](https://astronomy.stackexchange.com/a/14780/7982) to the question [V838 Monocerotis “light-echo” images morphed into nice video, but why so few original images?](https://astronomy.stackexchange.com/q/14660/7982) contains the following information below. There are other answers and more images there, so it's recommended to enjoy there as well.

**Question:** What does V838 Monocerotis look like today? Have there been subsequent light echo image sequences, or is the party over?

See also [Why weren't the Hubble light-echo images of V838 Monocerotis supplemented by ground telescopes?](https://astronomy.stackexchange.com/q/14781/7982)

---

---

The V838 Monocerotis *expansion* (not a supernova) and the observation of the subsequent "spectacular" light echo was quite a notable event! From [Nature **422**, 405-408 (27 March 2003)](http://www.nature.com/nature/journal/v422/n6930/abs/nature01508.html)

[![Nature Cover](https://i.sstatic.net/xU4aE.png)](https://i.sstatic.net/xU4aE.png)[![enter image description here](https://i.sstatic.net/TSrZZ.png)](https://i.sstatic.net/TSrZZ.png)

From [Astronom. J. **135**, 2, 2008](http://iopscience.iop.org/article/10.1088/0004-6256/135/2/605) or [ArXiv](http://arxiv.org/abs/0711.1495)

> "*.**Galactic light echoes are extremely rare. The only other known example of extent similar to that of V838 Mon was the echo produced by Nova GK Persei 1901** (Kapteyn 1902; Perrine 1902; Ritchey 1902). Following early misunderstandings, light-echo geometry was properly described by Couderc (1939), and more recent discussions are given by many authors, including Chevalier (1986), Felten (1991), Sparks (1994), Sugerman (2003), and references therein*".

It was the sole topic of an international conference [photo from here](http://www.ing.iac.es/conferences/v838mon/):

[![Conference](https://i.sstatic.net/BgHSZ.jpg)](https://i.sstatic.net/BgHSZ.jpg)
[Figure 2](http://www.nature.com/nature/journal/v422/n6930/fig_tab/nature01508_F2.html#figure-title) of the Nature paper describes the preservation of the actual light curve (history) within the structure of the light-echo shell:

[![enter image description here](https://i.sstatic.net/YztnU.jpg)](https://i.sstatic.net/YztnU.jpg)

> "**FIGURE 2. HST images of the light echoes**
> The apparently superluminal expansion of the echoes as light from the outburst propagates outward into surrounding dust is shown dramatically. Images were taken in 2002 on 30 April (a), 20 May (b), 2 September (c) and 28 October (d). Each frame is 83" times 83"; north is up and east to the left. Imaging on 30 April was obtained only in the B filter, but B, V and I were used on the other three dates, allowing us to make full-colour renditions. The time evolution of the stellar outburst (Fig. 1) is reflected by structures visible in these colour images. In b, for example, note the series of rings and filamentary structures, especially in the upper right quadrant. **Close examination shows that each set of rings has a sharp, blue outer edge, a dip in intensity nearer the star, and then a rebrightening to a redder plateau. Similar replicas of the outburst light curve are seen propagating outwards throughout all of the colour images**."

**also see:** This is an artificially constructed animation, morphing eight existing images to suggest what a higher cadence imaging campaign might have seen: <https://www.spacetelescope.org/videos/heic0617a/>

**Tags:** light, hubble-telescope, dust, v838-monocerotis

---

## 1 answers

### Answer by username_1 on 2018-11-07. Score: 6 | Accepted answer

I'm not an observational expert, but here's what I found.

I found this object (V838 Monocerotis) on the HST data archive.

<https://archive.stsci.edu/hst/search.php>

I input the 'Target Name' as "**V838 Monocerotis**", clicked all 'Imagers', 'Spectrographs', and 'Other,' and searched it.

(You can also do the exactly the same thing I did because this site is opened for everyone.)

And there are 199 images of this object. And the last observation was made in 2012. Unfortunately, I couldn't see any echoes in the picture taken in 2012. So I looked from the beginning. And I found this!

[![J9SF01020](https://i.sstatic.net/lrFVj.jpg)](https://i.sstatic.net/lrFVj.jpg)

This picture was taken from 2006-09-09 20:04:57 to 2006-09-10 01:14:57. Dataset number is J9SF01020. You can see that the shape of the echo. There are other pictures in the archive, but I couldn't see significant echo shape anymore after that.

**I'm sorry to say that the party is over, the echo was faded away.**

I also love this picture, it means a lot to me because this picture made me study Astronomy. Thanks for making me remind this memory.

P.S.: If you want other pictures, especially color pictures, check out this link too.

[http://hla.stsci.edu/hlaview.html#Images|filterText%3D%24filterTypes%3D|query\_string=V838%20Monocerotis&posfilename=&poslocalname=&posfilecount=&listdelimiter=whitespace&listformat=degrees&RA=106.020093&Dec=-3.847399&Radius=0.200000&inst-control=all&inst=ACS&inst=ACSGrism&inst=WFC3&inst=WFPC2&inst=NICMOS&inst=NICGRISM&inst=COS&inst=WFPC2-PC&inst=STIS&inst=FOS&inst=GHRS&imagetype=best∝\_id=&spectral\_elt=&proprietary=both&preview=1&output\_size=256&cutout\_size=12.8|ra=&dec=&sr=&level=ℑ=&inst=ACS%2CACSGrism%2CWFC3%2CWFPC2%2CNICMOS%2CNICGRISM%2CCOS%2CWFPC2-PC%2CSTIS%2CFOS%2CGHRS&ds=](http://hla.stsci.edu/hlaview.html#Images|filterText%3D%24filterTypes%3D|query_string=V838%20Monocerotis&posfilename=&poslocalname=&posfilecount=&listdelimiter=whitespace&listformat=degrees&RA=106.020093&Dec=-3.847399&Radius=0.200000&inst-control=all&inst=ACS&inst=ACSGrism&inst=WFC3&inst=WFPC2&inst=NICMOS&inst=NICGRISM&inst=COS&inst=WFPC2-PC&inst=STIS&inst=FOS&inst=GHRS&imagetype=best&prop_id=&spectral_elt=&proprietary=both&preview=1&output_size=256&cutout_size=12.8|ra=&dec=&sr=&level=&image=&inst=ACS%2CACSGrism%2CWFC3%2CWFPC2%2CNICMOS%2CNICGRISM%2CCOS%2CWFPC2-PC%2CSTIS%2CFOS%2CGHRS&ds=)

> **Comments:**
> **username_0**: Yes it's a really special event. I first learned about it in this [New York Times video](http://www.nytimes.com/video/science/100000003087764/echoes-of-light.html) and then asked [V838 Monocerotis “light-echo” images morphed into nice video, but why so few original images?](https://astronomy.stackexchange.com/q/14660/7982) The story that the narrator Dennis Overbye tells is quite interesting.  
> **username_1**: @uhoh My mistake, I clicked all 'Imagers', 'Spectrographs', and 'Other.'  
> **username_1**: @uhoh Also, this dataset is not sorted by time. I don't know why. By clicking 'Start Time' tap, you can get the list sorted by time.  
> **username_0**: Bingo, thank you, my mistake. I should't have assumed any particular sorting.  

---

