Condensed Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 12,118	$ 21,184
Short-term investments	4,934	0
Prepaid expenses and other current assets	303	418
Total current assets	17,355	21,602
Property and equipment, net	153	158
Long-term prepaid maintenance and supplies	91	91
Security deposit	14	14
Operating lease right-of-use asset	648	700
Financing lease right-of-use-asset	3,874	4,164
Total assets	22,135	26,729
Current liabilities:
Accounts payable	423	397
Accrued expenses	242	173
Accrued payroll related expenses	292	967
Current operating lease liability	247	245
Current financing lease liability	1,240	1,126
Total current liabilities	2,444	2,908
Long-term operating lease liability	475	521
Long-term financing lease liability	2,683	2,986
Total liabilities	5,602	6,415
Commitments and contingencies (see Note 9)
Stockholders’ equity:
Preferred stock $0.001 par value, authorized 2,500 shares; none issued and outstanding at March 31, 2023 and December 31, 2022	0	0
Common stock: $0.001 par value, authorized 47,500 shares; 24,330 and 23,973 shares issued and outstanding as of March 31, 2023 and December 31, 2022, respectively;	24	24
Additional paid in capital	204,825	203,585
Other comprehensive income (loss)	(2)	0
Accumulated deficit	(188,314)	(183,295)
Total stockholders’ equity	16,533	20,314
Total liabilities and stockholders’ equity	$ 22,135	$ 26,729

No definition available.

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Namespace Prefix:	atom_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).