How far back in time have you imaged?

[Starwiz]

Here's my personal best from the spring, IC4278 the little 'smudge' bottom centre.  At 230 million light years distant, those photons of light began their journey at the dawn of the dinosaurs on Earth.

[Knight of Clear Skies]

Think my record is 8 billion lights years, a mag 19.6 Quasar hiding in the background of this very ropy Draco Dwarf Galaxy image, taken with a DSLR and camera lens. Of course, it's just a faint dot, I expect a much larger instrument would be needed to take a spectrum and determine its redshift. I took some wide shots of the Virgo Cluster earlier this year with my 1600MM Cool but haven't yet checked if I picked up any Quasars. If anyone wants to look for distant objects in the background of your images I can recommend Martin Meredith's Pretty Deep Maps.

[Freddie]

About 10 billion LYs in this post

 

[laser_jock99]

Not far back in time - but I have imaged some really faint gallaxies when I did the Hubble Deep Field challenge. In the region of magnitude -21 to -22 I believe. So I guess many of the 'bright' quasars at huge distances would be in easy reach of this setup?

 

Hubble deep field with Lodestar X2 camera and 12" F4 Newtonian, 180s exposure.

Lodestar HDF by laserjock99, on Flickr

 

[ollypenrice]

Don't forget that the edge of the observable universe is about 46.5 billion lightyears away despite the fact that the universe is only about 13.7 billion years old. Keep expansion in mind when grappling with this stuff!

Olly

[Alien 13]

I think my old analogue TV might have you all beaten, some of the noise will be from just after the big bang.

Alan

[Knight of Clear Skies]

2 hours ago, ollypenrice said:

Don't forget that the edge of the observable universe is about 46.5 billion lightyears away despite the fact that the universe is only about 13.7 billion years old. Keep expansion in mind when grappling with this stuff!

Olly

Yes, this can get very confusing. I believe the distance to Quasars is normally quoted in light travel time, so you don't normally see figures over 13.7 billion years.

[SonnyE]

Well, not very far at all really.

Only two years. That's about when I started.

But do to massive troubles with equipment, I think my first picturd was around the summer of 2015.

Man, some of you guys must be ancient. 8 billion years?

[laser_jock99]

On 25/07/2017 at 23:31, SonnyE said:

Well, not very far at all really.

Only two years. That's about when I started.

But do to massive troubles with equipment, I think my first picturd was around the summer of 2015.

Man, some of you guys must be ancient. 8 billion years?

Well - putting it that way, since about 1985 when I got my first SLR camera!

[Galen Gilmore]

Man, some of you are half way across the observable universe. I haven't even gotten out of the Galaxy yet .

Furthest I've imaged is 6,500 light years with the lagoon nebula.

[Knight of Clear Skies]

On 25/07/2017 at 19:17, ollypenrice said:

Don't forget that the edge of the observable universe is about 46.5 billion lightyears away despite the fact that the universe is only about 13.7 billion years old. Keep expansion in mind when grappling with this stuff!

Olly

Double checked my possible Quasar, its redshift is listed as 2.01611. This gives a distance of 27.7 billion light years when plugged into this calculator, so I'm pretty sure 8 billion is the light travel time. Looking on Pretty Deep Maps I've definitely picked up some more distant ones around Virgo with my 1600MM Cool camera but it will take me a while to match them up.

So it's not actually that difficult to hoover up a few photons from the early universe. This is enough to carry out some genuine observations as Quasars can fluctuate in brightness quite rapidly. Some amateurs take spectra of the brightest ones, especially 3C 273, but if anyone fancies a real challenge they should aim for something more than 10 billion light years away.  The article I linked to mentions an hour long exposure was needed for a 15th magnitude star, using a 12" scope.

3 hours ago, Galen Gilmore said:

Man, some of you are half way across the observable universe. I haven't even gotten out of the Galaxy yet .

Furthest I've imaged is 6,500 light years with the lagoon nebula.

If you point your camera anywhere out of the plane of the Milky Way sometime, I promise you'll smash that record in a few minutes. Even a DSLR and portrait lens can go past the 100 million light year mark.

In some ways these records and PBs are a little pointless but they do serve to illustrate how capable even low-end amateur equipment is these days. I also find it enjoyable to try different things and search out the faint and distant objects hiding in my images, I'm frequently surprised by what it's possible to pick up.

[Uranium235]

Twin quasar QSO 0957+561 A/B - roughly 8bly:

A target thats a great example of gravitational lensing (as predicted by general relativity).

[brrttpaul]

what a great topic

[Ouroboros]

I did the Hubble Deep Field challenge too back in April 2015. 

At the time I noted that some of the galaxies I captured were between 1 and 2.5 billion LY away. Not bad for a SW 200p and a canon 450D. 

 

[HunterHarling]

Hubble deep field?! That's amazing! What did you use to get that deep?

The deepest I've gone is 210-340 million ly in Stevens quintet.

Hunter

[Stub Mandrel]

On 30/07/2017 at 15:31, laser_jock99 said:

Well - putting it that way, since about 1985 when I my first SLR!

I can trump that! This image is no later than 1984 and is probably 1983.

[Knight of Clear Skies]

12 hours ago, HunterHarling said:

Hubble deep field?! That's amazing! What did you use to get that deep?

@Ouruborus used a 200P scope and a 450D DSLR, but I'd be interested to hear the exposure details. From a dark site it's not difficult to pick up objects up to about mag 19, I've managed it with a 200mm lens and DSLR and about 30-40 minutes integration time (using 1 minute unguided subs). After that it gets more difficult to separate signal from skyglow, but mag 19 is enough to pick up some very distant Quasars and galaxies.

I used this rig to take some images of the Virgo Cluster back in March.

I've only just started looking at the data properly but I've found a couple Quasars at about mag 18-19 (one is 9 billion light years away) and some distant galaxy clusters. Shooting in mono, this is with just 20x1 minute exposures.

To detect faint point sources I believe you want as much aperture as possible (if a source is a point then the only way to gather more light is to increase the collection area). On the other hand, to pick up extended objects it's the focal ratio that matters (although with a big scope it's possible to increase the effective focal ratio by binning, trading resolution for signal). The rig above is better at detecting galaxies, provided they aren't too small, than Quasars or minor planets. Think I've got that right but hopefully someone will correct me if it's misleading.

[Stub Mandrel]

Mag 17 seems to be about the limit here, with my LP.

[Starwiz]

On 7/30/2017 at 19:56, Knight of Clear Skies said:

Double checked my possible Quasar, its redshift is listed as 2.01611. This gives a distance of 27.7 billion light years when plugged into this calculator, so I'm pretty sure 8 billion is the light travel time. Looking on Pretty Deep Maps I've definitely picked up some more distant ones around Virgo with my 1600MM Cool camera but it will take me a while to match them up.

This stuff really messes with my head.  So, if something is now 27.7 bly away, but the light travel time is only 8 bly, that leaves close to 20 bly extra distance gained in those 8 billion years since the light that was recently imaged began its journey.  How can that be possible?

Am I missing something? 

[Alien 13]

41 minutes ago, Starwiz said:

This stuff really messes with my head.  So, if something is now 27.7 bly away, but the light travel time is only 8 bly, that leaves close to 20 bly extra distance gained in those 8 billion years since the light that was recently imaged began its journey.  How can that be possible?

Am I missing something? 

Mine too 

Alan

[SonnyE]

On 7/30/2017 at 07:31, laser_jock99 said:

Well - putting it that way, since about 1985 when I got my first SLR camera!

 Reality check. 

[Space_Plane]

9 hours ago, Starwiz said:

This stuff really messes with my head.  So, if something is now 27.7 bly away, but the light travel time is only 8 bly, that leaves close to 20 bly extra distance gained in those 8 billion years since the light that was recently imaged began its journey.  How can that be possible?

Am I missing something? 

As olly mentioned in an earlier post, its down to the constant expansion of the universe.  In a vacuum, light will generally always travel at a fixed speed, and if it were travelling through a static universe, i suppose in 8 billion years it would travel 8 billion light years.

However, as the physical universe is constantly expanding (and accelerating) in all directions (not just from our point of view), then yes, this light has been moving for 8 billion years, but the space it is moving through has effectively been stretched, i always liked the idea of drawing pins (galaxies) pushed into a rubber band.  Imagine pulling the band, and the pins will move apart, as the "space" they are in expands.  The galaxies themselves don't really stretch, as all their stars and material are gravitationally bound together into the lovely swirls etc we see in the thread above.

This expansion will also effectively stretch the emitted light during its travel time, to longer and longer wavelengths, toward the red end of the spectrum (cosmological redshift), and as alan says above, given enough time, stretched all the way to microwaves and the static old tv's pick up 

However, thats probably long winded (and hopefully at least roughly correct), but something that fascinates me also 

[Knight of Clear Skies]

I think the above is correct but it does get confusing and I can't be 100% sure. One consequence of this expansion is that even if we could travel at the speed of light it would be impossible to reach some of these distant galaxies.

21 hours ago, Space_Plane said:

This expansion will also effectively stretch the emitted light during its travel time, to longer and longer wavelengths, toward the red end of the spectrum (cosmological redshift), and as alan says above, given enough time, stretched all the way to microwaves and the static old tv's pick up 

Just to add a common misconception about redshift: a redshifted object does not necessarily have a red appearance. If it's pumping out a great deal of UV light (for example, a starburst galaxy) that light is shifted into the blue end of the visible spectrum.