Let $$X_1,X_2, \ldots $$
X
1
,
X
2
,
…
be independent random uniform points in a bounded domain $$A \subset \mathbb {R}^d$$
A
⊂
R
d
with smooth boundary. Define the coverage threshold$$R_n$$
R
n
to be the smallest r such that A is covered by the balls of radius r centred on $$X_1,\ldots ,X_n$$
X
1
,
…
,
X
n
. We obtain the limiting distribution of $$R_n$$
R
n
and also a strong law of large numbers for $$R_n$$
R
n
in the large-n limit. For example, if A has volume 1 and perimeter $$|\partial A|$$
|
∂
A
|
, if $$d=3$$
d
=
3
then $$\mathbb {P}[n\pi R_n^3 - \log n - 2 \log (\log n) \le x]$$
P
[
n
π
R
n
3
-
log
n
-
2
log
(
log
n
)
≤
x
]
converges to $$\exp (-2^{-4}\pi ^{5/3} |\partial A| e^{-2 x/3})$$
exp
(
-
2
-
4
π
5
/
3
|
∂
A
|
e
-
2
x
/
3
)
and $$(n \pi R_n^3)/(\log n) \rightarrow 1$$
(
n
π
R
n
3
)
/
(
log
n
)
→
1
almost surely, and if $$d=2$$
d
=
2
then $$\mathbb {P}[n \pi R_n^2 - \log n - \log (\log n) \le x]$$
P
[
n
π
R
n
2
-
log
n
-
log
(
log
n
)
≤
x
]
converges to $$\exp (- e^{-x}- |\partial A|\pi ^{-1/2} e^{-x/2})$$
exp
(
-
e
-
x
-
|
∂
A
|
π
-
1
/
2
e
-
x
/
2
)
. We give similar results for general d, and also for the case where A is a polytope. We also generalize to allow for multiple coverage. The analysis relies on classical results by Hall and by Janson, along with a careful treatment of boundary effects. For the strong laws of large numbers, we can relax the requirement that the underlying density on A be uniform.