Disk Utility does not show a newly connected new/unformatted external USB3 drive I want to attach an external USB drive as a Time Machine target. What is the way to do this? I had thought Disk Utility would be able to help ..
This is Catalina on a  2020 Macbook pro . The external USB3 drive is connected via a USB &lt;--&gt; USB-C adapter to the Mac. The external drive power light is on so the electrical/physical connection is working.
But then Disk Utility only sees the original boot drive:

Update  Here is the output from diskutil list (not present):
13:45:54/~ $diskutil list
/dev/disk0 (internal, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *1.0 TB     disk0
   1:                        EFI EFI                     314.6 MB   disk0s1
   2:                 Apple_APFS Container disk1         1.0 TB     disk0s2

/dev/disk1 (synthesized):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      APFS Container Scheme -                      +1.0 TB     disk1
                                 Physical Store disk0s2
   1:                APFS Volume Macintosh HD            10.8 GB    disk1s1
   2:                APFS Volume Macintosh HD - Data     553.9 GB   disk1s2
   3:                APFS Volume Preboot                 81.7 MB    disk1s3
   4:                APFS Volume Recovery                535.6 MB   disk1s4
   5:                APFS Volume VM                      1.1 GB     disk1s5
You can see if the disk is attached easier in the command line.
diskutil list

Then if it’s recognized but not mounting, check for fsck processes. You can also click the view icon above where you selected Macintosh HD in your screenshot.