You will be given a definition of a task first, then some input of the task.
This task involves annotating the answer type to a given question that involve some kind of complex reasoning (including numerical reasoning). Note that the questions require looking at more than one part of the passage to answer. There are 3 possible answer types (i) spans, (ii) numbers and (iii) dates. If the answer can be found in the passage, label it as "span". If the answer is a number, label as "number". Similarly, label "date" if you think the answer to the given question is a date.

Passage: Precise measurements of atmospheric Absorption (electromagnetic radiation) were not made until 1888 and 1904. The temperature Stefan obtained was a median value of previous ones, 1950 C and the absolute thermodynamic one 2200 K. As 2.574 43.5, it follows from the law that the temperature of the Sun is 2.57 times greater than the temperature of the lamella, so Stefan got a value of 5430 C or 5700 K (the modern value is 5778 K). This was the first sensible value for the temperature of the Sun. Before this, values ranging from as low as 1800 C to as high as 13,000,000 C were claimed. The lower value of 1800 C was determined by Claude Pouillet (17901868) in 1838 using the DulongPetit law. Pouillet also took just half the value of the Suns correct energy flux.
Question: What year was the lowest estimate for the sun's temperature proposed?
Output:
date