diff --git a/hypertrace-graphql-explorer-schema/src/main/java/org/hypertrace/graphql/explorer/dao/GatewayServiceExploreRequestBuilder.java b/hypertrace-graphql-explorer-schema/src/main/java/org/hypertrace/graphql/explorer/dao/GatewayServiceExploreRequestBuilder.java
index 7b6d200a..057563c6 100644
--- a/hypertrace-graphql-explorer-schema/src/main/java/org/hypertrace/graphql/explorer/dao/GatewayServiceExploreRequestBuilder.java
+++ b/hypertrace-graphql-explorer-schema/src/main/java/org/hypertrace/graphql/explorer/dao/GatewayServiceExploreRequestBuilder.java
@@ -21,6 +21,7 @@
 import org.hypertrace.gateway.service.v1.common.Expression;
 import org.hypertrace.gateway.service.v1.common.Filter;
 import org.hypertrace.gateway.service.v1.common.TimeAggregation;
+import org.hypertrace.gateway.service.v1.explore.ExploreRequest.Builder;
 import org.hypertrace.graphql.explorer.request.ExploreRequest;
 import org.hypertrace.graphql.explorer.schema.argument.IntervalArgument;
 import org.hypertrace.graphql.metric.request.MetricAggregationRequest;
@@ -58,23 +59,31 @@ Single<org.hypertrace.gateway.service.v1.explore.ExploreRequest> buildRequest(
         this.filterConverter.convert(request.filterArguments()),
         this.buildAnyAggregations(request),
         this.buildAnyTimeAggregations(request),
-        (attributes, orderBys, groupBys, filter, aggregations, series) ->
-            org.hypertrace.gateway.service.v1.explore.ExploreRequest.newBuilder()
-                .setContext(request.scope())
-                .setStartTimeMillis(request.timeRange().startTime().toEpochMilli())
-                .setEndTimeMillis(request.timeRange().endTime().toEpochMilli())
-                .addAllSelection(attributes)
-                .addAllSelection(aggregations)
-                .addAllTimeAggregation(series)
-                .addAllOrderBy(orderBys)
-                .addAllGroupBy(groupBys)
-                .setLimit(request.limit())
-                .setIncludeRestGroup(request.includeRest())
-                .setOffset(request.offset())
-                .setFilter(filter)
-                .setSpaceId(request.spaceId().orElse("")) // String proto default value
-                .setGroupLimit(request.groupLimit().orElse(0)) // Int proto default value
-                .build());
+        (attributes, orderBys, groupBys, filter, aggregations, series) -> {
+          Builder builder =
+              org.hypertrace.gateway.service.v1.explore.ExploreRequest.newBuilder()
+                  .setContext(request.scope())
+                  .addAllSelection(attributes)
+                  .addAllSelection(aggregations)
+                  .addAllTimeAggregation(series)
+                  .addAllOrderBy(orderBys)
+                  .addAllGroupBy(groupBys)
+                  .setLimit(request.limit())
+                  .setIncludeRestGroup(request.includeRest())
+                  .setOffset(request.offset())
+                  .setFilter(filter)
+                  .setSpaceId(request.spaceId().orElse("")) // String proto default value
+                  .setGroupLimit(request.groupLimit().orElse(0)); // Int proto default value
+          request
+              .timeRange()
+              .ifPresent(
+                  timeRangeArgument -> {
+                    builder.setStartTimeMillis(timeRangeArgument.startTime().toEpochMilli());
+                    builder.setEndTimeMillis(timeRangeArgument.startTime().toEpochMilli());
+                  });
+
+          return builder.build();
+        });
   }
 
   private Single<Set<Expression>> buildAnyAggregations(ExploreRequest exploreRequest) {
diff --git a/hypertrace-graphql-explorer-schema/src/main/java/org/hypertrace/graphql/explorer/request/DefaultExploreRequestBuilder.java b/hypertrace-graphql-explorer-schema/src/main/java/org/hypertrace/graphql/explorer/request/DefaultExploreRequestBuilder.java
index c908007d..3d12f8c2 100644
--- a/hypertrace-graphql-explorer-schema/src/main/java/org/hypertrace/graphql/explorer/request/DefaultExploreRequestBuilder.java
+++ b/hypertrace-graphql-explorer-schema/src/main/java/org/hypertrace/graphql/explorer/request/DefaultExploreRequestBuilder.java
@@ -90,10 +90,8 @@ public Single<ExploreRequest> build(
             .deserializePrimitive(arguments, OffsetArgument.class)
             .orElse(DEFAULT_OFFSET);
 
-    TimeRangeArgument timeRange =
-        this.argumentDeserializer
-            .deserializeObject(arguments, TimeRangeArgument.class)
-            .orElseThrow();
+    Optional<TimeRangeArgument> timeRange =
+        this.argumentDeserializer.deserializeObject(arguments, TimeRangeArgument.class);
 
     List<AggregatableOrderArgument> requestedOrders =
         this.argumentDeserializer
@@ -141,7 +139,7 @@ public Single<ExploreRequest> build(
   public Single<ExploreRequest> build(
       GraphQlRequestContext requestContext,
       String explorerScope,
-      TimeRangeArgument timeRange,
+      Optional<TimeRangeArgument> timeRange,
       Optional<String> spaceId,
       int limit,
       int offset,
@@ -214,7 +212,7 @@ private Set<AttributeExpression> resolveGroupByExpressions(GroupByArgument group
   private static class DefaultExploreRequest implements ExploreRequest {
     GraphQlRequestContext context;
     String scope;
-    TimeRangeArgument timeRange;
+    Optional<TimeRangeArgument> timeRange;
     int limit;
     int offset;
     Set<AttributeRequest> attributeRequests;
diff --git a/hypertrace-graphql-explorer-schema/src/main/java/org/hypertrace/graphql/explorer/request/ExploreRequest.java b/hypertrace-graphql-explorer-schema/src/main/java/org/hypertrace/graphql/explorer/request/ExploreRequest.java
index f523c707..233c92d8 100644
--- a/hypertrace-graphql-explorer-schema/src/main/java/org/hypertrace/graphql/explorer/request/ExploreRequest.java
+++ b/hypertrace-graphql-explorer-schema/src/main/java/org/hypertrace/graphql/explorer/request/ExploreRequest.java
@@ -14,7 +14,7 @@
 public interface ExploreRequest extends ContextualRequest {
   String scope();
 
-  TimeRangeArgument timeRange();
+  Optional<TimeRangeArgument> timeRange();
 
   int limit();
 
diff --git a/hypertrace-graphql-explorer-schema/src/main/java/org/hypertrace/graphql/explorer/request/ExploreRequestBuilder.java b/hypertrace-graphql-explorer-schema/src/main/java/org/hypertrace/graphql/explorer/request/ExploreRequestBuilder.java
index b5046892..d6dfd0d1 100644
--- a/hypertrace-graphql-explorer-schema/src/main/java/org/hypertrace/graphql/explorer/request/ExploreRequestBuilder.java
+++ b/hypertrace-graphql-explorer-schema/src/main/java/org/hypertrace/graphql/explorer/request/ExploreRequestBuilder.java
@@ -24,7 +24,7 @@ Single<ExploreRequest> build(
   Single<ExploreRequest> build(
       GraphQlRequestContext requestContext,
       String explorerScope,
-      TimeRangeArgument timeRange,
+      Optional<TimeRangeArgument> timeRange,
       Optional<String> spaceId,
       int limit,
       int offset,
diff --git a/hypertrace-graphql-explorer-schema/src/main/java/org/hypertrace/graphql/explorer/schema/ExplorerSchema.java b/hypertrace-graphql-explorer-schema/src/main/java/org/hypertrace/graphql/explorer/schema/ExplorerSchema.java
index 961c0620..72376133 100644
--- a/hypertrace-graphql-explorer-schema/src/main/java/org/hypertrace/graphql/explorer/schema/ExplorerSchema.java
+++ b/hypertrace-graphql-explorer-schema/src/main/java/org/hypertrace/graphql/explorer/schema/ExplorerSchema.java
@@ -30,7 +30,7 @@ public interface ExplorerSchema {
   ExploreResultSet explore(
       @Deprecated @GraphQLName(ExplorerContextArgument.ARGUMENT_NAME) ExplorerContext context,
       @GraphQLName(ExplorerScopeArgument.ARGUMENT_NAME) String scope,
-      @GraphQLName(TimeRangeArgument.ARGUMENT_NAME) @GraphQLNonNull TimeRangeArgument timeRange,
+      @GraphQLName(TimeRangeArgument.ARGUMENT_NAME) TimeRangeArgument timeRange,
       @GraphQLName(SpaceArgument.ARGUMENT_NAME) String space,
       @GraphQLName(LimitArgument.ARGUMENT_NAME) int limit,
       @GraphQLName(OffsetArgument.ARGUMENT_NAME) int offset,
diff --git a/hypertrace-graphql-spaces-schema/src/main/java/org/hypertrace/graphql/spaces/dao/ExplorerBackedSpacesDao.java b/hypertrace-graphql-spaces-schema/src/main/java/org/hypertrace/graphql/spaces/dao/ExplorerBackedSpacesDao.java
index d08e2674..48ee0cac 100644
--- a/hypertrace-graphql-spaces-schema/src/main/java/org/hypertrace/graphql/spaces/dao/ExplorerBackedSpacesDao.java
+++ b/hypertrace-graphql-spaces-schema/src/main/java/org/hypertrace/graphql/spaces/dao/ExplorerBackedSpacesDao.java
@@ -75,7 +75,7 @@ private Single<ExploreRequest> buildRequest(GraphQlRequestContext context) {
             attributeRequest ->
                 new ActiveSpaceExploreRequest(
                     context,
-                    new FixedTimeRange(this.clock.instant()),
+                    Optional.of(new FixedTimeRange(this.clock.instant())),
                     attributeRequest,
                     this.metricAggregationRequestBuilder.build(
                         attributeRequest.attributeExpressionAssociation(),
@@ -153,14 +153,14 @@ private static class ActiveSpaceExploreRequest implements ExploreRequest {
     Optional<String> spaceId = Optional.empty();
     Optional<Integer> groupLimit = Optional.of(MAX_SPACES);
 
-    TimeRangeArgument timeRange;
+    Optional<TimeRangeArgument> timeRange;
     Set<MetricAggregationRequest> aggregationRequests;
     List<ExploreOrderArgument> orderArguments;
     Set<AttributeRequest> groupByAttributeRequests;
 
     ActiveSpaceExploreRequest(
         GraphQlRequestContext context,
-        TimeRangeArgument timeRange,
+        Optional<TimeRangeArgument> timeRange,
         AttributeRequest spaceIdRequest,
         MetricAggregationRequest spaceIdCountRequest) {
       this.context = context;
diff --git a/hypertrace-graphql-spaces-schema/src/test/java/org/hypertrace/graphql/spaces/dao/ExplorerBackedSpacesDaoTest.java b/hypertrace-graphql-spaces-schema/src/test/java/org/hypertrace/graphql/spaces/dao/ExplorerBackedSpacesDaoTest.java
index 88b8536b..7300f966 100644
--- a/hypertrace-graphql-spaces-schema/src/test/java/org/hypertrace/graphql/spaces/dao/ExplorerBackedSpacesDaoTest.java
+++ b/hypertrace-graphql-spaces-schema/src/test/java/org/hypertrace/graphql/spaces/dao/ExplorerBackedSpacesDaoTest.java
@@ -96,9 +96,10 @@ void makesAppropriateRequest() {
                         && request.offset() == 0
                         && request
                             .timeRange()
+                            .get()
                             .startTime()
                             .equals(Instant.parse("2021-01-01T00:00:00.00Z"))
-                        && request.timeRange().endTime().equals(this.mockEndTime)
+                        && request.timeRange().get().endTime().equals(this.mockEndTime)
                         && request.attributeRequests().isEmpty()
                         && request.aggregationRequests().equals(Set.of(this.mockSpaceCountRequest))
                         && request.orderArguments().size() == 1