Unable to iterate over array in Async observable in Angular

I'm trying to create a search page in angular, that queries results via Angulars $http Service and returns a defined object. The code looks similar to the tutorial the Angular documentation: https://angular.io/tutorial/toh-pt6#final-code-review.

However my app has a few key differences:

• The object being returned is an object containing an array, as opposed to just an array.
• My table in the view iterates over the array inside the object.

This is causing me an issue where the table in the view that iterates over this array throws a 'null' error before anything is searched, and therefore breaks the whole page from functioning properly

<tbody>
    <tr *ngFor="let email of (SearchResults$ | async).hits">
        <td><input type="checkbox" (change)="changeSelectedEmailsMap(email)" ></td>
        <td>{{email._source.from}}</td>
        <td>{{email._source.recipient}}</td>
        <td>{{email._source.date | date: 'dd/MM/yyyy hh:mm:ss'}}</td>
        <td>{{email._source.subject}}</td>
        <td><a routerLink="/detail/{{email.id}}" class="btn btn-outline-info btn-sm" role="button">View</a></td>
     </tr>
 </tbody>

For now, this is the only part of the page using these results, however it will be using other variables in SearchResults$

I have tried hiding the table entirely until results came in, using *ngIf="SearchResults$ !== null" on the entire table. However it still throws a null error once results come in and the table displays, leading me to believe the object isn't getting completely filled before the table takes a gander.

Is there any way to have the table only check hits when the variable exists?

Component.ts:

export class RepositorySearchComponent implements OnInit {

  @Input() repository: Repository;

  SearchResults$: Observable<EmailSearchResult>;

  private searchTerms = new Subject<string>();

  constructor(private emailService: EmailService) { }

  search(term: string){
    this.searchTerms.next(term);
  }


  ngOnInit() {
    this.SearchResults$ = this.searchTerms.pipe(
      debounceTime(300),

      distinctUntilChanged(),

      switchMap((term: string) => this.emailService.search(term, this.repository.id))
    );
  }
}