RKLB, ASTS Are Crushing Retail Space Trade On SpaceX IPO Buzz — But One Tiny Underdog Could Be The Real Moonshot

• SpaceX’s expected IPO, potentially targeting a nearly $2 trillion valuation, has boosted optimism around smaller space stocks.

• RKLB has surged 83% so far this month, SIDU climbed 82%, ASTS gained 68% and BKSY advanced 54% amid the sector-wide rally.

• Sidus Space has gained momentum through AI-focused satellite infrastructure, orbital data-storage partnerships, Earth-imaging systems and defense-related space tech.

Retail traders are crowding into Rocket Lab USA (RKLB) and AST SpaceMobile (ASTS) on mounting SpaceX IPO excitement, but one smaller space stock is quietly emerging as the sector’s cheapest high-upside play.

Retail Crowns RKLB, ASTS As Top Space Bets

A recent Stocktwits poll asking investors which space company they are most bullish on over the next five years showed Rocket Lab narrowly leading with 39% of votes, followed closely by AST SpaceMobile at 38%. Sidus Space (SIDU) received 16% support, while BlackSky Technology (BKSY) drew just 7%. The poll generated more than 3,100 votes.

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Excitement around space stocks accelerated after SpaceX moved closer to what could be the largest IPO in history, with the Elon Musk-led company reportedly seeking a valuation near $2 trillion. Investors see SpaceX as more than a rocket company, viewing it instead as a long-term orbital infrastructure and AI platform, spanning satellite broadband, launch systems and space transportation.

The expected listing has spurred interest across smaller space stocks seen as indirect beneficiaries of the broader SpaceX trade. Optimism grew further after FTSE Russell proposed faster index-entry rules for newly listed mega-cap IPOs, potentially opening the door for rapid benchmark inclusion and large passive-fund flows into SpaceX.

The rally has already been dramatic, with RKLB up 83% so far this month, narrowly ahead of Sidus Space at 82%, while AST SpaceMobile climbed 68% and BlackSky gained 54%.

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In overnight trading heading into Thursday, SIDU plunged 20% after the company priced a $100 million stock offering involving 19.7 million shares at $5.08 per share, priced at-the-market under Nasdaq rules. Sidus said the proceeds will be used for working capital and general corporate purposes, with the offering expected to close on May 29.

Meanwhile, ASTS fell 5%, RKLB slipped 4%, and BKSY edged down around 2%.

SIDU Quietly Emerges As Space Sector Underdog

Despite receiving far less retail attention than RKLB or ASTS, Sidus Space has quietly emerged as one of the sector’s strongest performers, with the stock also standing out as the only player among the four still showing analyst upside based on Koyfin consensus estimates, with an upside of about 64.5%, while AST SpaceMobile, Rocket Lab and BlackSky all currently imply downside from current levels.

Story Continues

The company’s momentum has been driven by growing investor interest in its AI-enabled satellite infrastructure and defense-focused orbital systems. Recent developments include a larger partnership with Lonestar Data Holdings for space-based data storage, the expansion of its AI-focused Fortis platform for defense and satellite missions, and successful imaging operations aboard its LizzieSat-3 satellite for monitoring and national security applications.

Sidus has also expanded partnerships for advanced Earth-imaging systems and AI-powered data processing in orbit.

Retail Bulls Back RKLB’s Space Expansion

Rocket Lab has become one of retail traders’ favorite space bets as the company expands deeper into defense and orbital infrastructure. The company recently secured an additional $816 million contract for the Space Development Agency’s missile-tracking satellite network, bringing the total to $ 1.331 million.

Rocket Lab has also been rapidly expanding through acquisitions across robotics, laser communications, spacecraft systems and precision manufacturing. Recent deals included Motiv Space Systems, whose technology supported NASA’s Mars rover programs, alongside earlier acquisitions of Mynaric, Geost, Optical Support and SolAero.

ASTS Rides Retail Optimism In Satellite Race

AST SpaceMobile has continued attracting strong retail interest as investors bet on the company’s long-term vision for space-based cellular broadband. Recent momentum has centered around progress in its BlueBird satellite rollout, with multiple satellites arriving at Cape Canaveral ahead of an upcoming SpaceX launch campaign.

The updates helped ease concerns following the loss of a previous satellite during Blue Origin’s New Glenn Mission-3 launch last month. CEO Abel Avellan has also maintained an aggressive deployment outlook, reiterating plans to launch 45 satellites this year and positioning ASTS as a high-speed, direct-to-smartphone broadband provider competing with Starlink and other satellite connectivity networks.

How Do Retail Traders Feel About RKLB, ASTS, SIDU, BKSY?

On Stocktwits, retail sentiment for ASTS and BKSY was ‘bullish’ amid ‘high’ message volume, while RKLB saw ‘neutral’ sentiment with similarly ‘high’ activity. SIDU stood out with ‘extremely bullish’ sentiment and ‘extremely high’ message volume.

Over the past month, SIDU has seen the biggest surge in retail activity among the group, with message volume surging 831%, while its watcher base has also climbed 13%. ASTS also saw heavy chatter, with message volume rising 327% and follower growth at 5.5%. Meanwhile, RKLB recorded a 121% jump in message volumes and a 6.6% increase in followers. BKSY lagged the broader retail frenzy, with message volume rising 14% and followers increasing 2.3%.

One user said, “ASTS will be a trillion dollar company. NO ONE is doing what they are with d2d sat connectivity.”

Another user called the Stocktwits poll “tricky” and said, “$BKSY may be acquired by one of the frontrunners. They are stalking.”

Over the past year, ASTS and RKLB have both surged 422%, while BKSY gained about 335% and SIDU climbed around 303%.

For updates and corrections, email newsroom[at]stocktwits[dot]com.

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Deepti Sri has no position in any of the stocks mentioned in this article. StockTwits’ news team content is for informational purposes only and is not intended as investment advice. For more, see our editorial policy. This article was originally published on StockTwits.

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