<blockquote>
<p>&quot;The instrument will be tested in Earth orbit for one year, ...&quot;</p>
<p>What would it then orbit?</p>
</blockquote>
<p>It will continue to orbit the Earth, at least for a while. It will eventually end up not orbiting the Earth because it will be placed in low Earth orbit, where orbits decay due to atmospheric drag.</p>
<p>The project is a technology demonstrator, which means a limited amount of funding.</p>

CC BY-SA 4.0
2019-06-06T18:30:14.433Z
*You're invited!* to write an answer to [Where would one deploy deep space atomic clocks?](https://space.stackexchange.com/q/36606/12102)
uhoh
CC BY-SA 4.0
2019-06-17T21:25:55.460Z
yeah, 'that particular' clock will de-orbit, but where will the working/longterm clock(s) orbit?
AwokeKnowing
CC BY-SA 4.0
2019-06-05T20:13:07.227Z
2019-06-05T20:13:07.227Z
2020-06-17T09:47:40.653Z
David Hammen
<p>The DSAC to be launched in June 2019 is a <a href="https://www.nasa.gov/mission_pages/tdm/main/overview.html" rel="nofollow noreferrer">Technology Demonstration Mission</a>,
in which they only test whether it works as well in space as it does on the ground.
If it passes the tests, similar devices could simplify navigation for future missions elsewhere in the solar system.</p>

<p>It is one of many payloads sharing space on an <a href="http://www.ga.com/general-atomics-orbital-test-bed-satellite-arrives-at-cape-canaveral" rel="nofollow noreferrer">Orbital Test Bed</a> satellite, which will probably remain in Earth orbit until its orbit decays.
The OTB is itself one of several payloads on the same <a href="https://www.spacex.com/stp-2" rel="nofollow noreferrer">launch vehicle</a>.</p>

CC BY-SA 4.0
2019-06-06T18:30:18.653Z
*You're invited!* to write an answer to [Where would one deploy deep space atomic clocks?](https://space.stackexchange.com/q/36606/12102)
uhoh
CC BY-SA 4.0
2019-06-17T21:24:30.680Z
Where would that 'elsewhere' be?
AwokeKnowing
CC BY-SA 4.0
2019-06-17T21:45:39.590Z
Anywhere outside the Earth-Moon system. See [this Space SE answer](https://space.stackexchange.com/a/36616) for explanation.
Mike G
CC BY-SA 4.0
2019-06-05T20:46:01.733Z
2019-06-05T20:46:01.733Z
Mike G
<p>I've seen multiple sources repeat the information that the <a href="https://en.wikipedia.org/wiki/Deep_Space_Atomic_Clock" rel="nofollow noreferrer">Deep Space Atomic Clock</a> will 'at first' orbit Earth, before moving on out of Earth orbit.</p>

<blockquote>
  <p>The Deep Space Atomic Clock (DSAC) is a miniaturized, ultra-precise
  mercury-ion atomic clock for precise radio navigation in deep space.
  It is orders of magnitude more stable than existing navigation clocks,
  and has been refined to limit drift of no more than 1 nanosecond in 10
  days.</p>
</blockquote>

<p><a href="https://en.wikipedia.org/wiki/Deep_Space_Atomic_Clock" rel="nofollow noreferrer">Wikipedia</a>: "Its development will include a test flight in low-Earth orbit"</p>

<p><a href="https://www.jpl.nasa.gov/news/news.php?feature=7415" rel="nofollow noreferrer">JPL</a>: "the instrument will be tested in Earth orbit for one year, with the goal of being ready for future missions to other worlds"</p>

<p>What would it then orbit? The Sun? Or some L point? Other planets? Or will multiple ones orbit all of the above?</p>

<p>Edit: for those wanting to close based on "not astronomy", have you considered astronomy does not have to be done from earth and indeed much of the data astronomers use often comes from probes and satellites in space.  Therefore 'how/where will this space beacon be used?' has strong impact on future of astronomy.</p>

CC BY-SA 4.0
2019-06-05T20:05:17.537Z
This should really be on "space exploration". I think there is a misunderstanding. The demonstration clock will stay in Earth orbit.  If it works well, then similar clocks can be installed on other spacecraft.
James K
CC BY-SA 4.0
2019-06-06T00:20:12.397Z
@JamesK  it seems I've just done such a thing; [Where would one deploy deep space atomic clocks?](https://space.stackexchange.com/q/36606/12102)
uhoh
CC BY-SA 4.0
2019-06-06T21:22:53.703Z
@JanDoggen While I think it matches the SpaceSE, first what should be checked, if it matches this site. The policy is that in the case of a topic overlap, the question remains where it is. In my opinion, this question is enough well about astronomy to remain here.
peterh
CC BY-SA 4.0
2019-06-07T05:20:41.037Z
@JanDoggen peterh is right. Our site's [Help Page](https://astronomy.stackexchange.com/help/on-topic) says "You may ask about [artificial satellites'] orbit, but not their purpose, usage and safety features. Questions about satellites with an astronomical purpose should be focused on astronomical usage and not broader questions such as the construction of the non-optical components." As this question is clearly about DSAC's **orbit**, and the 2 answers are both useful, I'm voting to reopen it as demonstrably *on-topic*.
Chappo Hasn't Forgotten
<orbit><artificial-satellite><navigation>
Where will the planned Deep Space Atomic Clock orbit "after" Earth?
AwokeKnowing
# Where will the planned Deep Space Atomic Clock orbit "after" Earth?

(Asked by: username_0 on 2019-06-05)

I've seen multiple sources repeat the information that the [Deep Space Atomic Clock](https://en.wikipedia.org/wiki/Deep_Space_Atomic_Clock) will 'at first' orbit Earth, before moving on out of Earth orbit.

> The Deep Space Atomic Clock (DSAC) is a miniaturized, ultra-precise
> mercury-ion atomic clock for precise radio navigation in deep space.
> It is orders of magnitude more stable than existing navigation clocks,
> and has been refined to limit drift of no more than 1 nanosecond in 10
> days.

[Wikipedia](https://en.wikipedia.org/wiki/Deep_Space_Atomic_Clock): "Its development will include a test flight in low-Earth orbit"

[JPL](https://www.jpl.nasa.gov/news/news.php?feature=7415): "the instrument will be tested in Earth orbit for one year, with the goal of being ready for future missions to other worlds"

What would it then orbit? The Sun? Or some L point? Other planets? Or will multiple ones orbit all of the above?

Edit: for those wanting to close based on "not astronomy", have you considered astronomy does not have to be done from earth and indeed much of the data astronomers use often comes from probes and satellites in space. Therefore 'how/where will this space beacon be used?' has strong impact on future of astronomy.

**Tags:** orbit, artificial-satellite, navigation
> **Comments:**
> **username_1**: This should really be on "space exploration". I think there is a misunderstanding. The demonstration clock will stay in Earth orbit.  If it works well, then similar clocks can be installed on other spacecraft.  
> **username_2**: @JamesK  it seems I've just done such a thing; [Where would one deploy deep space atomic clocks?](https://space.stackexchange.com/q/36606/12102)  
> **username_3**: @JanDoggen While I think it matches the SpaceSE, first what should be checked, if it matches this site. The policy is that in the case of a topic overlap, the question remains where it is. In my opinion, this question is enough well about astronomy to remain here.  
> **username_4**: @JanDoggen peterh is right. Our site's [Help Page](https://astronomy.stackexchange.com/help/on-topic) says "You may ask about [artificial satellites'] orbit, but not their purpose, usage and safety features. Questions about satellites with an astronomical purpose should be focused on astronomical usage and not broader questions such as the construction of the non-optical components." As this question is clearly about DSAC's **orbit**, and the 2 answers are both useful, I'm voting to reopen it as demonstrably *on-topic*.  

---

## 2 answers

### Answer by username_5 on 2019-06-05. Score: 4

> "The instrument will be tested in Earth orbit for one year, ..."
>
> What would it then orbit?

It will continue to orbit the Earth, at least for a while. It will eventually end up not orbiting the Earth because it will be placed in low Earth orbit, where orbits decay due to atmospheric drag.

The project is a technology demonstrator, which means a limited amount of funding.

> **Comments:**
> **username_2**: *You're invited!* to write an answer to [Where would one deploy deep space atomic clocks?](https://space.stackexchange.com/q/36606/12102)  
> **username_0**: yeah, 'that particular' clock will de-orbit, but where will the working/longterm clock(s) orbit?  

---

### Answer by username_6 on 2019-06-05. Score: 3

The DSAC to be launched in June 2019 is a [Technology Demonstration Mission](https://www.nasa.gov/mission_pages/tdm/main/overview.html),
in which they only test whether it works as well in space as it does on the ground.
If it passes the tests, similar devices could simplify navigation for future missions elsewhere in the solar system.

It is one of many payloads sharing space on an [Orbital Test Bed](http://www.ga.com/general-atomics-orbital-test-bed-satellite-arrives-at-cape-canaveral) satellite, which will probably remain in Earth orbit until its orbit decays.
The OTB is itself one of several payloads on the same [launch vehicle](https://www.spacex.com/stp-2).

> **Comments:**
> **username_2**: *You're invited!* to write an answer to [Where would one deploy deep space atomic clocks?](https://space.stackexchange.com/q/36606/12102)  
> **username_0**: Where would that 'elsewhere' be?  
> **username_6**: Anywhere outside the Earth-Moon system. See [this Space SE answer](https://space.stackexchange.com/a/36616) for explanation.  

---

