Comment by omgJustTest | Hacker News Reader

Comment by omgJustTest | Hacker News Reader

Methane detection from space![1] will aid in the detection of greenhouse gas emissions from abandoned well-heads, oil-fields, landfills and other large environmental polluters contributing to climate change. The IEA[3] has attributed nearly 30% of global temperature rise to methane, so the detection of the sources is becoming a critical factor in mitigating direct and indrect impacts of climate change. The sensors aboard the MethaneSAT, as well as other deployed capabilities, are largely based IR detections with tunable bandgap materials like HgCdTe[2] arrays. HgCdTe allows for the detection of non-ionizing IR via bandgap tuning of the direct semiconductor CdTe. IR bands, and thus chemical specific detections, can be selected based on the Hg doping. Similar technologies in the James Webb NIRCam enable detection of red-shifted gamma rays that are now heat photons.

[1]https://www.nature.com/articles/d41586-024-00600-z

[2]https://www.methanesat.org/satellite/

[3]https://www.iea.org/reports/global-methane-tracker-2022/meth...

Imagine the carbon released by putting all the satellites up there!

I was curious on this so did some quick searching around.

Average satellite launch releases 57 tons of Co2 [1]

2.75 million unplugged wells in the US that output "6.6m tons of Co2 worth of methane" [2], or put in another way each well puts out 2.4T of Co2e each per year.

With these numbers each sat would have to prevent 23.75 years worth of a well being uncapped to recoup the cost of launch (so would have to close one well for 23.75 years, or 24 wells for a little less than a year).

[1] https://www.linkedin.com/pulse/carbon-footprint-satellite-to...

[2] https://carboncontainmentlab.org/projects/plugging-abandoned....

(someone more informed feel free to correct any of these numbers, I am not an expert)

> The biggest event was a leak of 427 tonnes an hour in August, near Turkmenistan’s Caspian coast and a major pipeline.

From this Guardian article: https://www.theguardian.com/environment/2023/mar/06/revealed...

Your link says around 57 tons for a "typical" payload launched by the ESA using an Ariane 6 rocket and <15 tons for a payload that launches from a reusable platform. The parent article says these are launching using SpaceX rockets, which are reusable, so presumably their footprint is lower than an ESA satellite. They're also extremely small satellites and not exactly typical payloads. Possibly they can even fit multiple satellites on a single launch.

> 2.75 million unplugged wells in the US that output "6.6m tons of Co2 worth of methane" [2], or put in another way each well puts out 2.4T of Co2e each per year.

Per the article you cited, the 6.6m tonnes (not tons) of CO2e does not have a lot of empirical measurements behind it, and it may be much higher. That's one of the things these satellites can help to improve.

I think a better way to look at it is comparing the 57t of emissions with other sources of CO2 emissions. For example, a single cross-country flight puts out in the range of 300-350t of CO2 (~1t per passenger). So launching 6 of these satellites in separate launches would be equivalent to a single airliner flight, i.e. negligible in the grand scheme of things.

Clearly the utility of these instruments is not a single item.

One would imagine that monitoring of this sort is critical infrastructure for monitoring remote & continuous emitters.

Someone has already motivated many of these science missions, and they are not funded, to my knowledge, by industry. These are already rolled into govt investments so really the argument is not total CO2 balance, but what technologies can be deployed next year that will give you continuous reductions over time.

_Many_ people will argue their clean-tech _will eventually_ provide savings, not many can be installed next year at scale.

This is an obvious choice IMO, if for no other reason than people cannot out-right emit with no consequences.

For what it's worth, Spacex's next generation rocket burns methane directly, into CO2 which is a less potent greenhouse gas. That means that if solar power is used to create methane from the CO2 in the atmosphere, then the rocket will be carbon neutral. And if waste methane is used (commonly vented to atmosphere because the market is small yet it is expensive to capture) then each launch will actually be a net benefit for reducing atmospheric greenhouse gases.

Reply on news.ycombinator.com