The Senate Appropriations Committee is the body that translates White House budget requests into binding federal spending law. For NASA, it is the single most consequential legislative body: no matter what the House Science Committee authorises or the President requests, the final dollar figure depends on the Appropriations Committee's markup. When the FY2027 proposal to cut NASA to $18.8 billion emerged, the committee's chair, Sen. Susan Collins, expressed bipartisan concern, signalling resistance.

The committee has 30 members split between twelve subcommittees, one of which covers Commerce, Justice and Science and is chaired by Jerry Moran, giving him direct authority over NASA's appropriation. The subcommittee has repeatedly rejected White House cuts to NASA's Science budget, funding the agency at $24.4 billion in the previous cycle against an identical $18.8 billion request; in April 2026 Moran called a repeat FY2027 cut to $18.8 billion "a mistake", signalling the panel would again hold funding near FY2026 levels.

The FY2027 fight is particularly acute because Artemis is entering a critical capital phase, with the Lunar Gateway, advanced spacesuits, and Artemis III surface hardware all requiring sustained multi-year investment. A cut to $18.8 billion would force programme delays or cancellations at the precise moment Artemis II is demonstrating crewed deep-space capability.

On 12 May 2026, the Senate Appropriations Committee became the venue for the war's most significant constitutional moment. Appearing on $29 billion of Iran war spending, Defence Secretary Pete Hegseth testified under oath that Donald Trump holds 'all the authorities he needs under Article 2' and that 'we don't need' an AUMF. Senator Lisa Murkowski asked the opening question; her threatened AUMF was rendered procedurally moot by Hegseth's answer .

The exchange exposed a structural distinction that has run beneath the Iran war since 28 February 2026: the Appropriations Committee controls spending on the conflict but has no authority to force a formal authorisation for it. That power belongs to the Senate Armed Services Committee (SASC) and the House Armed Services Committee (HASC), neither of which has produced a binding instrument. The Appropriations Committee can theoretically attach a rider blocking war funds, but doing so risks a veto and has not been tested. The reaction to Hegseth's testimony was described as intense bipartisan frustration (WaPo); the war has now consumed $29 billion under no signed presidential instrument, a streak of 75 consecutive days .

On 21 July, Hegseth returned to the committee to give the war's first official cost figure, $37.5 billion, with no accounting basis for whether it was obligated, appropriated or incremental spending. The committee was already weighing OMB director Russell Vought's 24 June letter to Speaker Mike Johnson requesting $87.6 billion, of which $67 billion is the Defence component covering Iran. Ranking member Patty Murray said the panel would not "rubber-stamp a request to bankroll this war", noting the department received over $1 trillion last year and is asking $1.3 trillion for the current fiscal year; Dick Durbin said Hegseth and General Caine "can't explain how this money is going to be spent".

Common Questions

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What is the difference between the Senate Appropriations Committee and Armed Services Committee?

The Appropriations Committee controls how much money agencies receive (spending). The Armed Services Committee authorises military activities — it can legally approve or constrain what the military does. For the Iran war, Appropriations reviews the $29 billion cost but cannot force a war authorisation; that power rests with SASC (Senate Armed Services Committee) and HASC.

What is the difference between authorisation and appropriation for NASA?

The House Science Committee authorises programmes (sets policy and direction). The Appropriations Committee funds them. NASA can be authorised for a programme but receive no money if appropriations fail.Source: background

How does the Senate Appropriations Committee affect NASA?

It writes the spending bills that set NASA budgets into law. The President requests a figure; the committee can accept, raise, or cut it. It has rejected identical White House NASA cuts before, funding the agency at $24.4 billion last cycle.Source: background

What is the $87.6 billion funding request for?

OMB director Russell Vought wrote to Speaker Mike Johnson on 24 June 2026 requesting $87.6 billion, of which $67 billion is the Defence component covering the Iran war; the Senate Appropriations Committee had not set a markup or vote date as of late July.Source: Lowdown reporting

How much has the Iran war cost the US so far?

Defence Secretary Pete Hegseth told the Senate Appropriations Committee on 21 July 2026 that the Iran campaign has cost $37.5 billion to date, the first official figure Washington has attached to the war, without saying whether it was obligated, appropriated or incremental spending.Source: Lowdown reporting

What did Hegseth say to the Senate Appropriations Committee about Iran?

On 12 May 2026, Hegseth told the committee that Trump has 'all the authorities he needs under Article 2' and that an AUMF on Iran is not required. The testimony was the first time a cabinet officer formally stated this as policy rather than leaving it implicit.Source: US Senate Appropriations Committee testimony

Is the Senate Appropriations Committee cutting the NASA budget?

The committee has resisted White House cuts to NASA, with chair Susan Collins expressing bipartisan concern over the FY2027 request to cut NASA to $18.8 billion. Congress funded NASA at $24.4 billion the previous cycle against an identical request, and the CJS Subcommittee chair Jerry Moran has stated he intends to fund the agency at roughly FY2026 levels.Source: Senate Appropriations Committee, Space Symposium

Can the Senate Appropriations Committee stop funding the Iran war?

Theoretically yes, by attaching a spending rider blocking Iran war funds. In practice, such a rider would risk a presidential veto and require a veto-proof majority (67 senators) to override. No such rider has been filed as of 13 May 2026, and committee members have not indicated one is being drafted.

What is Congress's position on the FY2027 NASA budget?

Broadly resistant. The Senate Appropriations chair expressed bipartisan concern. Congress rejected an identical $18.8 billion request the prior year and passed $24.4 billion instead.Source: background

Source Material

United States Senate Committee on Appropriations - Wikipedia

How the World Sees Them

White House

Sees Appropriations as a spending validator, not a war-authority gate. Hegseth's Article 2 testimony was given to the Appropriations panel precisely because the administration does not concede it owes SASC or HASC an authorisation.

NASA stakeholders

View the committee as the last institutional firewall against White House science budget cuts, given Collins and Moran's public resistance to the $18.8 billion proposal.

Congressional Democrats

Frustrated that the only committee currently reviewing Iran war costs lacks the authority to mandate a formal AUMF. View the Appropriations hearing as a constitutional accountability gap.