From the research paper - Our results indicate that aerosol and fomite transmission of HCoV-19 is plausible, as the virus can remain viable in aerosols for multiple hours and on surfaces up to days.
https://www.medrxiv.org/content/10.1101/2020.03.09.20033217v2.full.pdf
"HCoV-19 remained viable in aerosols throughout the duration of our experiment (3 hours) with a reduction in infectious titer from 103.5 to 102.7 TCID50/L, similar to the reduction observed for SARS-CoV-1, from 104.3 to 103.5 TCID50/mL (Figure 1A). HCoV-19 was most stable on plastic and stainless steel and viable virus could be detected up to 72 hours post application (Figure 1A), though the virus titer was greatly reduced (plastic from 103.7 to 100.6 TCID50/mL after 72 hours, stainless steel from 103.7 to 100.6 TCID50/mL after 48 hours). SARS-CoV-1 had similar stability kinetics (polypropylene from 103.4 to 100.7 TCID50/mL after 72 hours, stainless steel from 103.6 to 100.6 TCID50/mL after 48 hours). No viable virus could be measured after 4 hours on copper for HCoV-19 and 8 hours for SARS-CoV-1, or after 24 hours on cardboard for HCoV-19 and 8 hours for 39 SARS-CoV-1 (Figure 1A)."
and then this:
What I find interesting about this is that COVID-19 behaves very similarly to SARS - especially "This indicates that differences in the epidemiology of these viruses likely arise from other factors, including high viral loads in the upper respiratory tract and the potential for individuals infected with HCoV-19 to shed and transmit the virus while asymptomatic"